refactor(svc): tidy the rust services and build tooling (#2735)

Cargo.lock

@@ -2011,6 +2011,7 @@ dependencies = [
  "axum",
  "base64",
  "fluxer_common",
+ "futures-util",
  "hex",
  "rand 0.10.1",
  "reqwest",
@@ -2039,6 +2040,7 @@ dependencies = [
  "reqwest",
  "serde_json",
  "sha2 0.11.0",
+ "tempfile",
  "thiserror",
  "time",
  "tracing",

fluxer_app_proxy/Cargo.toml

@@ -10,6 +10,7 @@ anyhow = "1.0.104"
 axum = { version = "0.8.9", features = ["macros"] }
 base64 = "0.22"
 fluxer_common = { path = "../fluxer_common" }
+futures-util = { version = "0.3.32", default-features = false, features = ["std"] }
 hex = "0.4"
 rand = "0.10"
 reqwest = { version = "0.13.4", default-features = false, features = ["json", "rustls", "stream", "gzip", "brotli", "deflate"] }

fluxer_app_proxy/src/bootstrap.rs

@@ -132,7 +132,7 @@ pub fn inject_bootstrap(
     let media = media_endpoint.trim_end_matches('/');
 
     let nonced = html.replace("{{CSP_NONCE_PLACEHOLDER}}", nonce);
-    let nonced = apply_static_preconnect(&nonced, static_cdn);
+    let nonced = apply_static_preconnect(nonced, static_cdn);
     let nonced = nonced.replace("{{STATIC_CDN_ENDPOINT}}", static_cdn);
     let nonced = apply_media_preconnect(&nonced, media, static_cdn);
 
@@ -143,20 +143,14 @@ pub fn inject_bootstrap(
         return nonced.replace("{{FLUXER_BOOTSTRAP}}", script_tag);
     }
 
-    if let Some(pos) = nonced.find("<head>") {
+    let insert_at = nonced
-        let insert_at = pos + "<head>".len();
+        .find("<head>")
-        let mut result = String::with_capacity(nonced.len() + script_tag.len() + 3);
+        .map(|pos| pos + "<head>".len())
-        result.push_str(&nonced[..insert_at]);
+        .or_else(|| {
-        result.push_str("\n\t\t");
+            let pos = nonced.find("<head ")?;
-        result.push_str(script_tag);
+            nonced[pos..].find('>').map(|close| pos + close + 1)
-        result.push_str(&nonced[insert_at..]);
+        });
-        return result;
+    if let Some(insert_at) = insert_at {
-    }
-
-    if let Some(pos) = nonced.find("<head ")
-        && let Some(close) = nonced[pos..].find('>')
-    {
-        let insert_at = pos + close + 1;
         let mut result = String::with_capacity(nonced.len() + script_tag.len() + 3);
         result.push_str(&nonced[..insert_at]);
         result.push_str("\n\t\t");
@@ -168,15 +162,14 @@ pub fn inject_bootstrap(
     nonced
 }
 
-fn apply_static_preconnect(html: &str, static_cdn: &str) -> String {
+fn apply_static_preconnect(mut html: String, static_cdn: &str) -> String {
     if !static_cdn.is_empty() {
-        return html.to_owned();
+        return html;
     }
-    let mut stripped = html.to_owned();
     for tag in STATIC_PRECONNECT_TAGS {
-        stripped = stripped.replace(&format!("{tag}\n"), "").replace(tag, "");
+        html = html.replace(&format!("{tag}\n"), "").replace(tag, "");
     }
-    stripped
+    html
 }
 
 fn apply_media_preconnect(html: &str, media: &str, static_cdn: &str) -> String {

fluxer_app_proxy/src/config.rs

@@ -309,30 +309,20 @@ impl fmt::Display for CspReportUri {
     }
 }
 
-fn warn_invalid(error: InvalidAppProxyEnvironmentError) {
+fn warn_invalid(error: &InvalidAppProxyEnvironmentError) {
     tracing::warn!(%error, "ignoring invalid app proxy environment value");
 }
 
 fn parse_optional_http_url(name: &'static str, value: Option<String>) -> Option<HttpUrl> {
     let value = value?;
-    match HttpUrl::parse(name, &value) {
+    HttpUrl::parse(name, &value).inspect_err(warn_invalid).ok()
-        Ok(url) => Some(url),
-        Err(error) => {
-            warn_invalid(error);
-            None
-        }
-    }
 }
 
 fn parse_optional_http_endpoint(name: &'static str, value: Option<String>) -> Option<HttpEndpoint> {
     let value = value?;
-    match HttpEndpoint::parse(name, &value) {
+    HttpEndpoint::parse(name, &value)
-        Ok(endpoint) => Some(endpoint),
+        .inspect_err(warn_invalid)
-        Err(error) => {
+        .ok()
-            warn_invalid(error);
-            None
-        }
-    }
 }
 
 fn parse_env_or_warn<T: std::str::FromStr>(name: &str, raw: &str, default: T) -> T {
@@ -434,25 +424,19 @@ fn read_csp_sources(name: &'static str) -> Vec<CspSource> {
         .split([',', ' ', '\t', '\n'])
         .map(str::trim)
         .filter(|source| !source.is_empty())
-        .filter_map(|source| match CspSource::parse(name, source) {
+        .filter_map(|source| {
-            Ok(source) => Some(source),
+            CspSource::parse(name, source)
-            Err(error) => {
+                .inspect_err(warn_invalid)
-                warn_invalid(error);
+                .ok()
-                None
-            }
         })
         .collect()
 }
 
 fn read_csp_report_uri(name: &'static str) -> Option<CspReportUri> {
     let value = cfg::non_empty_env(name)?;
-    match CspReportUri::parse(name, &value) {
+    CspReportUri::parse(name, &value)
-        Ok(report_uri) => Some(report_uri),
+        .inspect_err(warn_invalid)
-        Err(error) => {
+        .ok()
-            warn_invalid(error);
-            None
-        }
-    }
 }
 
 impl AppProxyConfig {
@@ -474,13 +458,10 @@ impl AppProxyConfig {
         );
         let s3_uploads_bucket = cfg::read_env("FLUXER_S3_BUCKET_UPLOADS", "fluxer-uploads");
         let s3_uploads_endpoint = s3_public_endpoint.as_ref().and_then(|endpoint| {
-            match endpoint.with_host_prefix("FLUXER_S3_BUCKET_UPLOADS", s3_uploads_bucket.trim()) {
+            endpoint
-                Ok(endpoint) => Some(endpoint),
+                .with_host_prefix("FLUXER_S3_BUCKET_UPLOADS", s3_uploads_bucket.trim())
-                Err(error) => {
+                .inspect_err(warn_invalid)
-                    warn_invalid(error);
+                .ok()
-                    None
-                }
-            }
         });
 
         Self {
@@ -499,7 +480,7 @@ impl AppProxyConfig {
                 "FLUXER_STATIC_CDN_ENDPOINT",
                 cfg::non_empty_env("FLUXER_STATIC_CDN_ENDPOINT"),
             ),
-            s3_public_endpoint: s3_public_endpoint.clone(),
+            s3_public_endpoint,
             s3_uploads_endpoint,
             discovery_upstream_url: resolve_discovery_upstream_url_from_env(),
             discovery_refresh_interval_ms: parse_env_or_warn(

fluxer_app_proxy/src/csp.rs

@@ -287,15 +287,11 @@ fn extend_runtime_s3_sources(target: &mut Vec<String>, runtime_sources: &Runtime
 }
 
 fn extend_from(target: &mut Vec<String>, extra: &[CspSource], defaults: &[&str]) {
-    for source in defaults {
+    for source in defaults
-        if target.iter().any(|existing| existing == source) {
+        .iter()
-            continue;
+        .copied()
-        }
+        .chain(extra.iter().map(CspSource::as_str))
-        target.push((*source).to_owned());
+    {
-    }
-
-    for source in extra {
-        let source = source.as_str();
         if target.iter().any(|existing| existing == source) {
             continue;
         }

fluxer_app_proxy/src/routes/android_association.rs

@@ -2,47 +2,33 @@
 
 use axum::{
     Json,
-    http::{HeaderValue, header},
+    http::header,
     response::{IntoResponse, Response},
 };
 use serde_json::json;
 
 pub async fn assetlinks() -> Response {
-    let body = json!([
+    let body = ["com.fluxer", "com.fluxer.canary"].map(|package_name| {
-        {
+        json!({
             "relation": [
                 "delegate_permission/common.handle_all_urls",
                 "delegate_permission/common.get_login_creds"
             ],
             "target": {
                 "namespace": "android_app",
-                "package_name": "com.fluxer",
+                "package_name": package_name,
                 "sha256_cert_fingerprints": [
                     "91:E4:98:E1:B8:A6:C8:BA:99:41:5E:DB:29:78:29:6B:6C:58:BA:A5:E2:D2:A6:49:CE:C6:2D:A7:A8:29:C7:BC"
                 ]
             }
-        },
+        })
-        {
+    });
-            "relation": [
-                "delegate_permission/common.handle_all_urls",
-                "delegate_permission/common.get_login_creds"
-            ],
-            "target": {
-                "namespace": "android_app",
-                "package_name": "com.fluxer.canary",
-                "sha256_cert_fingerprints": [
-                    "91:E4:98:E1:B8:A6:C8:BA:99:41:5E:DB:29:78:29:6B:6C:58:BA:A5:E2:D2:A6:49:CE:C6:2D:A7:A8:29:C7:BC"
-                ]
-            }
-        }
-    ]);
 
-    let mut response = Json(body).into_response();
+    (
-    response.headers_mut().insert(
+        [(header::CACHE_CONTROL, "public, max-age=1800")],
-        header::CACHE_CONTROL,
+        Json(body),
-        HeaderValue::from_static("public, max-age=1800"),
+    )
-    );
+        .into_response()
-    response
 }
 
 #[cfg(test)]

fluxer_app_proxy/src/routes/apple_association.rs

@@ -2,7 +2,7 @@
 
 use axum::{
     Json,
-    http::{HeaderValue, header},
+    http::header,
     response::{IntoResponse, Response},
 };
 use serde_json::json;
@@ -19,10 +19,9 @@ pub async fn apple_app_site_association() -> Response {
         }
     });
 
-    let mut response = Json(body).into_response();
+    (
-    response.headers_mut().insert(
+        [(header::CACHE_CONTROL, "public, max-age=1800")],
-        header::CACHE_CONTROL,
+        Json(body),
-        HeaderValue::from_static("public, max-age=1800"),
+    )
-    );
+        .into_response()
-    response
 }

fluxer_app_proxy/src/routes/assets_proxy.rs

@@ -9,9 +9,7 @@ use axum::{
 };
 use std::path::{Path as FsPath, PathBuf};
 use std::time::Duration;
-use tokio::io::{AsyncWriteExt, DuplexStream};
 use tokio::sync::{OwnedSemaphorePermit, TryAcquireError};
-use tokio_util::io::ReaderStream;
 
 use super::file_stream::stream_file;
 use super::spa_static::{CORS_ALLOW_ANY_VALUE, asset_cache_control, guess_mime, is_font_mime};
@@ -19,7 +17,6 @@ use super::spa_static::{CORS_ALLOW_ANY_VALUE, asset_cache_control, guess_mime, i
 const ASSET_REQUEST_TIMEOUT: Duration = Duration::from_secs(15);
 const PRECOMPRESSED_VARIANTS: &[(&str, &str)] = &[("br", "br"), ("gzip", "gz")];
 const MAX_ASSET_SIZE_BYTES: u64 = 100 * 1024 * 1024;
-const UPSTREAM_ASSET_PUMP_BUFFER_BYTES: usize = 64 * 1024;
 const UPSTREAM_FAILURE_CACHE_CONTROL: &str = "no-store";
 const UPSTREAM_FAILURE_STRIPPED_HEADERS: &[&str] = &[
     "cdn-cache-control",
@@ -148,38 +145,59 @@ pub async fn proxy_assets(
     response_headers.insert(header::CONTENT_SECURITY_POLICY, state.csp.asset_header());
     response_headers.remove("content-security-policy-report-only");
 
-    let body = Body::from_stream(upstream_asset_body(upstream_response, upstream_slot));
+    let body = upstream_asset_body(upstream_response, upstream_slot);
     let mut response = Response::new(body);
     *response.status_mut() = status;
     *response.headers_mut() = response_headers;
     response
 }
 
+struct UpstreamAssetReadState {
+    response: reqwest::Response,
+    _permit: OwnedSemaphorePermit,
+    remaining_bytes: u64,
+}
+
 fn upstream_asset_body(
-    mut upstream_response: reqwest::Response,
+    upstream_response: reqwest::Response,
     upstream_slot: OwnedSemaphorePermit,
-) -> ReaderStream<DuplexStream> {
+) -> Body {
-    let (writer, reader) = tokio::io::duplex(UPSTREAM_ASSET_PUMP_BUFFER_BYTES);
+    let state = UpstreamAssetReadState {
-    tokio::spawn(async move {
+        response: upstream_response,
-        let _upstream_slot = upstream_slot;
+        _permit: upstream_slot,
-        let mut writer = writer;
+        remaining_bytes: MAX_ASSET_SIZE_BYTES,
-        loop {
+    };
-            match upstream_response.chunk().await {
+    Body::from_stream(futures_util::stream::try_unfold(
-                Ok(Some(chunk)) => {
+        state,
-                    if writer.write_all(&chunk).await.is_err() {
+        |mut state| async move {
-                        return;
+            let Some(chunk) = state
-                    }
+                .response
-                }
+                .chunk()
-                Ok(None) => break,
+                .await
-                Err(err) => {
+                .inspect_err(|err| {
                     tracing::warn!(%err, "upstream asset body ended early");
-                    return;
+                })
-                }
+                .map_err(axum::Error::new)?
+            else {
+                return Ok(None);
+            };
+            let chunk_bytes = chunk.len() as u64;
+            if chunk_bytes > state.remaining_bytes {
+                tracing::warn!(
+                    maximum_bytes = MAX_ASSET_SIZE_BYTES,
+                    remaining_bytes = state.remaining_bytes,
+                    chunk_bytes,
+                    "upstream asset body exceeds size cap"
+                );
+                return Err(axum::Error::new(std::io::Error::new(
+                    std::io::ErrorKind::InvalidData,
+                    format!("upstream asset body exceeds {MAX_ASSET_SIZE_BYTES} bytes"),
+                )));
             }
-        }
+            state.remaining_bytes -= chunk_bytes;
-        let _ = writer.shutdown().await;
+            Ok(Some((chunk, state)))
-    });
+        },
-    ReaderStream::new(reader)
+    ))
 }
 
 pub(super) async fn serve_local_asset(

fluxer_app_proxy/src/routes/mod.rs

@@ -13,7 +13,7 @@ use axum::{
     Router,
     extract::Request,
     http::{HeaderName, HeaderValue, header},
-    middleware::{Next, from_fn, from_fn_with_state},
+    middleware::{Next, from_fn},
     response::{IntoResponse, Response},
     routing::get,
 };
@@ -56,10 +56,7 @@ pub fn build_router(state: AppState) -> Router {
         .fallback(get(spa_index::spa_catch_all))
         .layer(from_fn(request_id_middleware))
         .layer(from_fn(cache_headers_middleware))
-        .layer(from_fn_with_state(
+        .layer(from_fn(security_headers_middleware))
-            state.clone(),
-            security_headers_middleware,
-        ))
         .layer(
             CompressionLayer::new()
                 .compress_when(DefaultPredicate::new().and(NotForContentType::const_new("font/"))),
@@ -68,14 +65,13 @@ pub fn build_router(state: AppState) -> Router {
         .with_state(state)
 }
 
-async fn security_headers_middleware(
+async fn security_headers_middleware(request: Request, next: Next) -> Response {
-    axum::extract::State(_state): axum::extract::State<AppState>,
-    request: Request,
-    next: Next,
-) -> Response {
     let mut response = next.run(request).await;
-    let headers = response.headers_mut();
+    set_security_headers(response.headers_mut());
+    response
+}
 
+fn set_security_headers(headers: &mut axum::http::HeaderMap) {
     set_static_header(
         headers,
         header::STRICT_TRANSPORT_SECURITY,
@@ -89,8 +85,6 @@ async fn security_headers_middleware(
         HeaderName::from_static("permissions-policy"),
         PERMISSIONS_POLICY_VALUE,
     );
-
-    response
 }
 
 async fn cache_headers_middleware(request: Request, next: Next) -> Response {

fluxer_app_proxy/src/routes/spa_index.rs

@@ -410,19 +410,7 @@ fn build_spa_response(
     } else {
         headers.insert(header::CACHE_CONTROL, HeaderValue::from_static("no-cache"));
     }
-    headers.insert(
+    super::set_security_headers(headers);
-        header::STRICT_TRANSPORT_SECURITY,
-        HeaderValue::from_static("max-age=31536000; includeSubDomains; preload"),
-    );
-    headers.insert(
-        header::X_CONTENT_TYPE_OPTIONS,
-        HeaderValue::from_static("nosniff"),
-    );
-    headers.insert(header::X_FRAME_OPTIONS, HeaderValue::from_static("DENY"));
-    headers.insert(
-        header::REFERRER_POLICY,
-        HeaderValue::from_static("strict-origin-when-cross-origin"),
-    );
     headers.insert(
         axum::http::HeaderName::from_static("accept-ch"),
         HeaderValue::from_static(ACCEPT_CH_VALUE),
@@ -431,11 +419,6 @@ fn build_spa_response(
         axum::http::HeaderName::from_static("critical-ch"),
         HeaderValue::from_static(CRITICAL_CH_VALUE),
     );
-    headers.insert(
-        axum::http::HeaderName::from_static("permissions-policy"),
-        HeaderValue::from_static(super::PERMISSIONS_POLICY_VALUE),
-    );
-
     #[cfg(feature = "time-freeze")]
     {
         if let Some(tf) = time_freeze_header

fluxer_common/Cargo.toml

@@ -13,6 +13,7 @@ maxminddb = "0.28.1"
 moka = { version = "0.12.15", features = ["sync"] }
 reqwest = { version = "0.13.4", default-features = false, features = ["blocking", "rustls"] }
 serde_json = "1.0.150"
+tempfile = "3.27.0"
 time = { version = "0.3.47", features = ["formatting", "macros", "parsing"] }
 tracing = "0.1.44"
 base64 = "0.22"

fluxer_common/src/config.rs

@@ -203,12 +203,12 @@ fn is_default_port(scheme: &str, port: u16) -> bool {
     )
 }
 
-fn strip_trailing_dot(host: &str) -> &str {
-    host.strip_suffix('.').unwrap_or(host)
-}
-
 fn canonicalize_domain(value: &str) -> String {
-    strip_trailing_dot(value.trim().to_lowercase().as_str()).to_owned()
+    let mut domain = value.trim().to_lowercase();
+    if domain.ends_with('.') {
+        domain.pop();
+    }
+    domain
 }
 
 fn default_port(scheme: &str) -> u16 {
@@ -285,10 +285,10 @@ where
 }
 
 pub fn normalize_public_endpoint(url: &str, base_domain: &str, public_port: Option<u16>) -> String {
-    let domain = canonicalize_domain(base_domain);
     let Some(port) = public_port.filter(|port| *port != 0) else {
         return url.to_owned();
     };
+    let domain = canonicalize_domain(base_domain);
     if domain.is_empty() {
         return url.to_owned();
     }

fluxer_common/src/geoip.rs

@@ -19,7 +19,6 @@ use std::{
     path::Path,
     time::{Duration, SystemTime},
 };
-use time::OffsetDateTime;
 
 const DEFAULT_COUNTRY_CODE: &str = "US";
 const GEOIP_CACHE_TTL: Duration = Duration::from_secs(10 * 60);
@@ -242,7 +241,6 @@ fn download_s3_object(
         );
     };
     fs::create_dir_all(parent)?;
-    let temp_path = temporary_download_path(destination);
     let request = signed_s3_get_request(config, bucket, key)?;
     let mut response = reqwest::blocking::Client::new()
         .get(request.url)
@@ -253,29 +251,14 @@ fn download_s3_object(
         })?;
     if !response.status().is_success() {
         let status = response.status();
-        let _ = fs::remove_file(&temp_path);
         anyhow::bail!("failed to download GeoIP database from s3://{bucket}/{key}: HTTP {status}");
     }
-    {
+    let mut file = tempfile::Builder::new().make_in(parent, |path| File::create_new(path))?;
-        let mut file = File::create(&temp_path)?;
+    io::copy(&mut response, &mut file)?;
-        io::copy(&mut response, &mut file)?;
+    file.persist(destination).map_err(|err| err.error)?;
-    }
-    fs::rename(&temp_path, destination).inspect_err(|_err| {
-        let _ = fs::remove_file(&temp_path);
-    })?;
     Ok(())
 }
 
-fn temporary_download_path(destination: &Path) -> std::path::PathBuf {
-    let pid = std::process::id();
-    let now = OffsetDateTime::now_utc().unix_timestamp_nanos();
-    let file_name = destination
-        .file_name()
-        .and_then(|value| value.to_str())
-        .unwrap_or("geoip.mmdb");
-    destination.with_file_name(format!("{file_name}.tmp-{pid}-{now}"))
-}
-
 struct SignedS3Request {
     url: reqwest::Url,
     headers: reqwest::header::HeaderMap,

fluxer_snowflakes/src/generator.rs

@@ -66,20 +66,15 @@ where
 
     pub async fn generate(&mut self) -> anyhow::Result<u64> {
         let mut timestamp = self.current_relative_timestamp()?;
-        if let Some(last_timestamp) = self.last_timestamp {
+        match self.last_timestamp {
-            if timestamp < last_timestamp {
+            Some(last_timestamp) if timestamp <= last_timestamp => {
                 timestamp = last_timestamp;
-            }
-            if timestamp == last_timestamp {
                 self.sequence = (self.sequence + 1) & MAX_SEQUENCE;
                 if self.sequence == 0 {
                     timestamp = self.wait_until_next_timestamp(last_timestamp).await?;
                 }
-            } else {
-                self.sequence = 0;
             }
-        } else {
+            _ => self.sequence = 0,
-            self.sequence = 0;
         }
         self.last_timestamp = Some(timestamp);
         Ok(create_snowflake_from_relative_timestamp(

fluxer_snowflakes/src/router_impl.rs

@@ -4,10 +4,10 @@ use crate::types::{SERVICE_NAME, SnowflakeRequest, SnowflakeResponse};
 use fluxer_svc::config::ServiceConfig;
 use fluxer_svc::hash_ring::HashRing;
 use fluxer_svc::metrics::ServiceMetrics;
-use fluxer_svc::transport::{NatsTransport, TransportMessage, TransportSubscriber};
+use fluxer_svc::transport::{NatsMessage, NatsTransport, TransportMessage, TransportSubscriber};
 use std::sync::Arc;
 use std::sync::atomic::{AtomicBool, AtomicU32, Ordering};
-use std::time::Duration;
+use std::time::{Duration, Instant};
 use tokio::task::JoinSet;
 use tracing::{debug, info, warn};
 
@@ -61,8 +61,10 @@ pub async fn run_round_robin_router(
     config: &ServiceConfig,
     transport: NatsTransport,
 ) -> anyhow::Result<()> {
-    let request_subject = format!("svc.{SERVICE_NAME}");
+    anyhow::ensure!(
-    let queue_group = format!("{SERVICE_NAME}-router");
+        config.max_concurrent_requests > 0,
+        "snowflake router request concurrency must be positive"
+    );
     let picker = Arc::new(SnowflakeShardPicker::new(config.shard_count));
     let mut tasks = JoinSet::new();
     let health_addr = config.listen_addr;
@@ -82,84 +84,12 @@ pub async fn run_round_robin_router(
             .await
         }
     });
-    let req_transport = transport.clone();
+    tasks.spawn(serve_requests(
-    tasks.spawn(async move {
+        transport,
-        loop {
+        picker,
-            let mut sub = req_transport
+        http_metrics,
-                .subscribe_queue(&request_subject, &queue_group)
+        config.max_concurrent_requests,
-                .await?;
+    ));
-            info!(subject = request_subject, "snowflake router listening for requests");
-            loop {
-                let msg = tokio::select! {
-                    msg_opt = sub.next() => {
-                        let Some(msg) = msg_opt else {
-                            warn!("snowflake router request subscription stream ended, will re-subscribe");
-                            break;
-                        };
-                        msg
-                    }
-                    _ = req_transport.wait_for_reconnect() => {
-                        info!("NATS reconnected, re-subscribing snowflake router request listener");
-                        break;
-                    }
-                };
-                let transport = req_transport.clone();
-                let picker = picker.clone();
-                if msg.payload().len() > MAX_ROUTER_REQUEST_BYTES {
-                    warn!(
-                        payload_bytes = msg.payload().len(),
-                        max_payload_bytes = MAX_ROUTER_REQUEST_BYTES,
-                        "rejecting oversized snowflake request"
-                    );
-                    reply_json_error(&msg, &transport, "request_too_large").await;
-                    continue;
-                }
-                let request: SnowflakeRequest = match serde_json::from_slice(msg.payload()) {
-                    Ok(request) => request,
-                    Err(error) => {
-                        warn!(error = %error, "failed to decode snowflake request");
-                        reply_json_error(&msg, &transport, "decode_error").await;
-                        continue;
-                    }
-                };
-                tokio::spawn(async move {
-                    let shard_id = picker.pick_shard(&request);
-                    let shard_subject = format!("svc.{SERVICE_NAME}.shard.{shard_id}");
-                    let payload = match rmp_serde::to_vec(&request) {
-                        Ok(payload) => payload,
-                        Err(error) => {
-                            warn!(error = %error, "failed to encode snowflake shard request");
-                            reply_json_error(&msg, &transport, "encode_error").await;
-                            return;
-                        }
-                    };
-                    let response_bytes = match transport
-                        .request(&shard_subject, &payload, SHARD_REQUEST_TIMEOUT)
-                        .await
-                    {
-                        Ok(response_bytes) => response_bytes,
-                        Err(error) => {
-                            debug!(error = %error, shard_id, "snowflake shard request failed");
-                            reply_json_error(&msg, &transport, "shard_unavailable").await;
-                            return;
-                        }
-                    };
-                    let response: SnowflakeResponse = match rmp_serde::from_slice(&response_bytes) {
-                        Ok(response) => response,
-                        Err(error) => {
-                            debug!(error = %error, shard_id, "failed to decode snowflake shard response");
-                            reply_json_error(&msg, &transport, "shard_decode_error").await;
-                            return;
-                        }
-                    };
-                    if msg.has_reply() {
-                        let response_json = serde_json::to_vec(&response).unwrap_or_default();
-                        let _ = msg.reply(&transport, &response_json).await;
-                    }
-                });
-            }
-        }
-    });
     tokio::select! {
         result = tasks.join_next() => {
             match result {
@@ -177,15 +107,136 @@ pub async fn run_round_robin_router(
     }
 }
 
-async fn reply_json_error(
+async fn serve_requests(
-    msg: &fluxer_svc::transport::NatsMessage,
+    transport: NatsTransport,
-    transport: &NatsTransport,
+    picker: Arc<SnowflakeShardPicker>,
-    error: &str,
+    metrics: Arc<ServiceMetrics>,
+    max_concurrent_requests: usize,
+) -> anyhow::Result<()> {
+    let request_subject = format!("svc.{SERVICE_NAME}");
+    let queue_group = format!("{SERVICE_NAME}-router");
+    let mut requests = JoinSet::new();
+    loop {
+        let mut sub = transport
+            .subscribe_queue(&request_subject, &queue_group)
+            .await?;
+        info!(
+            subject = request_subject,
+            max_concurrent_requests, "snowflake router listening for requests"
+        );
+        loop {
+            let msg = tokio::select! {
+                result = requests.join_next(), if !requests.is_empty() => {
+                    if let Err(error) = result.expect("nonempty snowflake request set") {
+                        warn!(error = %error, "snowflake request task failed");
+                    }
+                    continue;
+                }
+                msg = sub.next() => {
+                    let Some(msg) = msg else {
+                        warn!("snowflake router request subscription stream ended, will re-subscribe");
+                        break;
+                    };
+                    msg
+                }
+            };
+            while let Some(result) = requests.try_join_next() {
+                if let Err(error) = result {
+                    warn!(error = %error, "snowflake request task failed");
+                }
+            }
+            metrics.record_request();
+            if requests.len() >= max_concurrent_requests {
+                debug!(
+                    max_concurrent_requests,
+                    "shedding overloaded snowflake router request"
+                );
+                metrics.record_request_error();
+                reply_json_error(&msg, &transport, "overloaded").await;
+                continue;
+            }
+            requests.spawn(handle_request(
+                msg,
+                transport.clone(),
+                picker.clone(),
+                metrics.clone(),
+            ));
+        }
+    }
+}
+
+async fn handle_request(
+    msg: NatsMessage,
+    transport: NatsTransport,
+    picker: Arc<SnowflakeShardPicker>,
+    metrics: Arc<ServiceMetrics>,
 ) {
+    let started = Instant::now();
+    match forward_request(msg.payload(), &transport, &picker, &metrics).await {
+        Ok(response) => {
+            if msg.has_reply() {
+                let payload = serde_json::to_vec(&response)
+                    .expect("snowflake responses contain only JSON-serializable strings");
+                reply(&msg, &transport, &payload).await;
+            }
+        }
+        Err(error) => {
+            metrics.record_request_error();
+            reply_json_error(&msg, &transport, error).await;
+        }
+    }
+    metrics.record_request_duration(started.elapsed().as_millis() as u64);
+}
+
+async fn forward_request(
+    payload: &[u8],
+    transport: &NatsTransport,
+    picker: &SnowflakeShardPicker,
+    metrics: &ServiceMetrics,
+) -> Result<SnowflakeResponse, &'static str> {
+    if payload.len() > MAX_ROUTER_REQUEST_BYTES {
+        warn!(
+            payload_bytes = payload.len(),
+            max_payload_bytes = MAX_ROUTER_REQUEST_BYTES,
+            "rejecting oversized snowflake request"
+        );
+        return Err("request_too_large");
+    }
+    let request: SnowflakeRequest = serde_json::from_slice(payload).map_err(|error| {
+        warn!(error = %error, "failed to decode snowflake request");
+        "decode_error"
+    })?;
+    let shard_id = picker.pick_shard(&request);
+    let shard_subject = format!("svc.{SERVICE_NAME}.shard.{shard_id}");
+    let payload = rmp_serde::to_vec(&request).map_err(|error| {
+        warn!(error = %error, "failed to encode snowflake shard request");
+        "encode_error"
+    })?;
+    metrics.record_shard_forward();
+    let response_bytes = transport
+        .request(&shard_subject, &payload, SHARD_REQUEST_TIMEOUT)
+        .await
+        .map_err(|error| {
+            debug!(error = %error, shard_id, "snowflake shard request failed");
+            "shard_unavailable"
+        })?;
+    rmp_serde::from_slice(&response_bytes).map_err(|error| {
+        debug!(error = %error, shard_id, "failed to decode snowflake shard response");
+        "shard_decode_error"
+    })
+}
+
+async fn reply_json_error(msg: &NatsMessage, transport: &NatsTransport, error: &str) {
     if msg.has_reply() {
-        let error_response =
+        let payload = serde_json::to_vec(&serde_json::json!({ "error": error }))
-            serde_json::to_vec(&serde_json::json!({ "error": error })).unwrap_or_default();
+            .expect("snowflake error responses contain only a JSON-serializable string");
-        let _ = msg.reply(transport, &error_response).await;
+        reply(msg, transport, &payload).await;
+    }
+}
+
+async fn reply(msg: &NatsMessage, transport: &NatsTransport, payload: &[u8]) {
+    if let Err(error) = msg.reply(transport, payload).await {
+        warn!(error = %error, "failed to reply to snowflake request");
     }
 }
 

fluxer_svc/src/config.rs

@@ -75,8 +75,9 @@ impl ServiceConfig {
         };
 
         let mode = match optional_from(&get, "FLUXER_SVC_MODE").as_deref() {
+            None | Some("router") => Mode::Router,
             Some("shard") => Mode::Shard,
-            _ => Mode::Router,
+            Some(other) => anyhow::bail!("unsupported FLUXER_SVC_MODE: {other}"),
         };
 
         let shard_count = optional_from(&get, "FLUXER_SVC_SHARD_COUNT")

fluxer_svc/src/hash_ring.rs

@@ -9,6 +9,10 @@ impl HashRing {
         Self { shard_count }
     }
 
+    pub fn shard_count(&self) -> u32 {
+        self.shard_count
+    }
+
     pub fn owner(&self, route_key: &str) -> u32 {
         let mut best_shard = 0u32;
         let mut best_score = 0u64;

fluxer_svc/src/router.rs

@@ -2,11 +2,15 @@
 
 use crate::config::ServiceConfig;
 use crate::hash_ring::HashRing;
-use crate::metrics::{ServiceMetrics, now_ms};
+use crate::metrics::ServiceMetrics;
-use crate::transport::{Transport, TransportMessage, TransportSubscriber, reply_message};
+use crate::transport::{
+    Transport, TransportMessage, TransportSubscriber, reply_bytes, reply_json_error,
+};
+use anyhow::Context;
+use futures::stream::{FuturesUnordered, StreamExt};
 use moka::future::Cache;
 use std::sync::Arc;
-use std::time::Duration;
+use std::time::{Duration, Instant};
 use tokio::sync::{Semaphore, TryAcquireError};
 use tokio::task::JoinSet;
 use tracing::{debug, info, warn};
@@ -14,6 +18,7 @@ use tracing::{debug, info, warn};
 pub(crate) const SHARD_REQUEST_TIMEOUT: Duration = Duration::from_secs(5);
 const INFLIGHT_TTL: Duration = Duration::from_millis(200);
 const INFLIGHT_MAX_ENTRIES: u64 = 10_000;
+const MAX_BROADCAST_CONCURRENCY: usize = 32;
 const MAX_ROUTER_REQUEST_BYTES: usize = 2 * 1024 * 1024;
 const LEGACY_SHARD_DECODE_ERROR: &[u8] = br#"{"error":"shard_request_decode_error"}"#;
 type InflightKey = (String, String);
@@ -30,6 +35,13 @@ pub trait RouterService: Send + Sync + 'static {
         None
     }
 
+    fn is_broadcast_request(_request: &Self::Request) -> bool {
+        false
+    }
+    fn is_broadcast_acknowledgement(_response: &Self::Response) -> bool {
+        false
+    }
+
     fn l1_lookup(&self, _req: &Self::Request) -> Option<Self::Response> {
         None
     }
@@ -111,6 +123,88 @@ async fn dispatch_to_shard<S: RouterService>(
     }
 }
 
+async fn forward_to_all_shards<S: RouterService>(
+    transport: &impl Transport,
+    service: &S,
+    ring: &HashRing,
+    request: &S::Request,
+) -> anyhow::Result<Vec<u8>> {
+    let payload = rmp_serde::to_vec_named(request)
+        .context("failed to encode broadcast request as msgpack")?;
+    let payload = payload.as_slice();
+    let service_name = service.service_name();
+    let deadline = tokio::time::Instant::now() + SHARD_REQUEST_TIMEOUT;
+    let request_shard = |shard_id| async move {
+        let timeout = deadline.saturating_duration_since(tokio::time::Instant::now());
+        if timeout.is_zero() {
+            anyhow::bail!("broadcast deadline expired before shard {shard_id}");
+        }
+        let subject = format!("svc.{service_name}.shard.{shard_id}");
+        let response_bytes = transport
+            .request(&subject, payload, timeout)
+            .await
+            .with_context(|| format!("broadcast request to shard {shard_id} failed"))?;
+        let response = rmp_serde::from_slice::<S::Response>(&response_bytes)
+            .with_context(|| format!("invalid broadcast response from shard {shard_id}"))?;
+        if !S::is_broadcast_acknowledgement(&response) {
+            anyhow::bail!("unexpected broadcast acknowledgement from shard {shard_id}");
+        }
+        anyhow::Ok(response)
+    };
+
+    let mut shard_ids = 0..ring.shard_count();
+    let mut pending = FuturesUnordered::new();
+    for shard_id in shard_ids.by_ref().take(MAX_BROADCAST_CONCURRENCY) {
+        pending.push(request_shard(shard_id));
+    }
+
+    let mut acknowledgement = None;
+    let mut first_error = None;
+    while let Some(result) = pending.next().await {
+        match result {
+            Ok(response) => acknowledgement = Some(response),
+            Err(error) => {
+                first_error.get_or_insert(error);
+            }
+        }
+        if first_error.is_none()
+            && let Some(shard_id) = shard_ids.next()
+        {
+            pending.push(request_shard(shard_id));
+        }
+    }
+    if let Some(error) = first_error {
+        return Err(error);
+    }
+    let acknowledgement = acknowledgement.context("broadcast request has no configured shards")?;
+    if S::CACHES_RESPONSES {
+        rmp_serde::to_vec_named(&acknowledgement)
+            .context("failed to encode broadcast acknowledgement as msgpack")
+    } else {
+        serde_json::to_vec(&acknowledgement)
+            .context("failed to encode broadcast acknowledgement as json")
+    }
+}
+
+async fn reply_json_response(
+    message: &impl TransportMessage,
+    transport: &impl Transport,
+    response: &impl serde::Serialize,
+    metrics: &ServiceMetrics,
+) {
+    if !message.has_reply() {
+        return;
+    }
+    match serde_json::to_vec(response) {
+        Ok(payload) => reply_bytes(message, transport, &payload).await,
+        Err(error) => {
+            warn!(error = %error, subject = message.subject(), "failed to encode router response");
+            metrics.record_request_error();
+            reply_json_error(message, transport, "encode_error").await;
+        }
+    }
+}
+
 async fn handle_router_request<S, T>(
     msg: T::Message,
     transport: T,
@@ -122,7 +216,7 @@ async fn handle_router_request<S, T>(
     S: RouterService,
     T: Transport,
 {
-    let request_start = now_ms();
+    let request_start = Instant::now();
     metrics.record_request();
     if msg.payload().len() > MAX_ROUTER_REQUEST_BYTES {
         warn!(
@@ -131,12 +225,7 @@ async fn handle_router_request<S, T>(
             "rejecting oversized router request"
         );
         metrics.record_request_error();
-        if msg.has_reply() {
+        reply_json_error(&msg, &transport, "request_too_large").await;
-            let error_response =
-                serde_json::to_vec(&serde_json::json!({"error": "request_too_large"}))
-                    .unwrap_or_default();
-            let _ = reply_message(&msg, &transport, &error_response).await;
-        }
         return;
     }
     let request: S::Request = match serde_json::from_slice(msg.payload()) {
@@ -144,25 +233,20 @@ async fn handle_router_request<S, T>(
         Err(err) => {
             warn!(error = %err, "failed to decode incoming request");
             metrics.record_request_error();
-            if msg.has_reply() {
+            reply_json_error(&msg, &transport, "decode_error").await;
-                let error_response =
-                    serde_json::to_vec(&serde_json::json!({"error": "decode_error"}))
-                        .unwrap_or_default();
-                let _ = reply_message(&msg, &transport, &error_response).await;
-            }
             return;
         }
     };
     let request = Arc::new(request);
+    let broadcast = S::is_broadcast_request(&request);
 
-    if let Some(cached) = service.l1_lookup(&request) {
+    if S::CACHES_RESPONSES
+        && !broadcast
+        && let Some(cached) = service.l1_lookup(&request)
+    {
         metrics.record_cache_hit();
-        let elapsed = (now_ms() - request_start).max(0) as u64;
+        metrics.record_request_duration(request_start.elapsed().as_millis() as u64);
-        metrics.record_request_duration(elapsed);
+        reply_json_response(&msg, &transport, &cached, &metrics).await;
-        if msg.has_reply() {
-            let response_bytes = serde_json::to_vec(&cached).unwrap_or_default();
-            let _ = reply_message(&msg, &transport, &response_bytes).await;
-        }
         return;
     }
 
@@ -170,7 +254,9 @@ async fn handle_router_request<S, T>(
     metrics.record_cache_miss();
     metrics.record_shard_forward();
 
-    let coalesce_result = if let Some(coalesce_key) = S::coalesce_key(&request) {
+    let coalesce_result = if broadcast {
+        forward_to_all_shards::<S>(&transport, service.as_ref(), ring.as_ref(), &request).await
+    } else if let Some(coalesce_key) = S::coalesce_key(&request) {
         let forward_transport = transport.clone();
         let forward_service = service.clone();
         let forward_ring = ring.clone();
@@ -208,36 +294,31 @@ async fn handle_router_request<S, T>(
         .await
     };
 
-    let elapsed = (now_ms() - request_start).max(0) as u64;
+    metrics.record_request_duration(request_start.elapsed().as_millis() as u64);
-    metrics.record_request_duration(elapsed);
 
     match coalesce_result {
         Ok(response_bytes) => {
             if !S::CACHES_RESPONSES {
                 if msg.has_reply() {
-                    let _ = reply_message(&msg, &transport, &response_bytes).await;
+                    reply_bytes(&msg, &transport, &response_bytes).await;
                 }
                 return;
             }
             match rmp_serde::from_slice::<S::Response>(&response_bytes) {
                 Ok(response) => {
-                    service.l1_insert(&request, &response);
+                    if !broadcast {
-                    if msg.has_reply() {
+                        service.l1_insert(&request, &response);
-                        let json = serde_json::to_vec(&response).unwrap_or_default();
-                        let _ = reply_message(&msg, &transport, &json).await;
                     }
+                    reply_json_response(&msg, &transport, &response, &metrics).await;
                 }
                 Err(err) => {
                     debug!(error = %err, "failed to decode shard response");
                     if msg.has_reply() {
                         if serde_json::from_slice::<serde_json::Value>(&response_bytes).is_ok() {
-                            let _ = reply_message(&msg, &transport, &response_bytes).await;
+                            reply_bytes(&msg, &transport, &response_bytes).await;
                             return;
                         }
-                        let error_response =
+                        reply_json_error(&msg, &transport, "shard_decode_error").await;
-                            serde_json::to_vec(&serde_json::json!({"error": "shard_decode_error"}))
-                                .unwrap_or_default();
-                        let _ = reply_message(&msg, &transport, &error_response).await;
                     }
                 }
             }
@@ -245,12 +326,7 @@ async fn handle_router_request<S, T>(
         Err(err) => {
             debug!(error = %err, "shard request failed (coalesced)");
             metrics.record_request_error();
-            if msg.has_reply() {
+            reply_json_error(&msg, &transport, "shard_unavailable").await;
-                let error_response =
-                    serde_json::to_vec(&serde_json::json!({"error": "shard_unavailable"}))
-                        .unwrap_or_default();
-                let _ = reply_message(&msg, &transport, &error_response).await;
-            }
         }
     }
 }
@@ -267,7 +343,6 @@ where
     let ring = Arc::new(HashRing::new(config.shard_count));
     let name = service.service_name().to_owned();
     let request_subject = format!("svc.{name}");
-    let invalidate_subject = format!("svc.{name}.invalidate.>");
     let queue_group = format!("{name}-router");
 
     let metrics = Arc::new(ServiceMetrics::default());
@@ -295,6 +370,7 @@ where
     let req_metrics = metrics.clone();
     let req_permits = Arc::new(Semaphore::new(config.max_concurrent_requests));
     tasks.spawn(async move {
+        let mut requests = JoinSet::new();
         loop {
             let mut sub = req_transport
                 .subscribe_queue(&request_subject, &req_queue)
@@ -307,6 +383,12 @@ where
 
             loop {
                 let msg = tokio::select! {
+                    result = requests.join_next(), if !requests.is_empty() => {
+                        if let Err(err) = result.expect("nonempty router request set") {
+                            warn!(error = %err, "router request task failed");
+                        }
+                        continue;
+                    }
                     msg_opt = sub.next() => {
                         let Some(msg) = msg_opt else {
                             warn!("router request subscription stream ended, will re-subscribe");
@@ -314,24 +396,20 @@ where
                         };
                         msg
                     }
-                    _ = req_transport.wait_for_reconnect() => {
-                        info!("NATS reconnected, re-subscribing router request listener");
-                        break;
-                    }
                 };
 
+                while let Some(result) = requests.try_join_next() {
+                    if let Err(err) = result {
+                        warn!(error = %err, "router request task failed");
+                    }
+                }
                 let permit = match req_permits.clone().try_acquire_owned() {
                     Ok(permit) => permit,
                     Err(TryAcquireError::NoPermits) => {
                         debug!("shedding router request, no permits available");
                         req_metrics.record_request();
                         req_metrics.record_request_error();
-                        if msg.has_reply() {
+                        reply_json_error(&msg, &req_transport, "overloaded").await;
-                            let error_response =
-                                serde_json::to_vec(&serde_json::json!({"error": "overloaded"}))
-                                    .unwrap_or_default();
-                            let _ = reply_message(&msg, &req_transport, &error_response).await;
-                        }
                         continue;
                     }
                     Err(TryAcquireError::Closed) => return anyhow::Ok(()),
@@ -341,7 +419,7 @@ where
                 let ring = ring.clone();
                 let inflight = inflight.clone();
                 let metrics = req_metrics.clone();
-                tokio::spawn(async move {
+                requests.spawn(async move {
                     let _permit = permit;
                     handle_router_request::<S, _>(msg, transport, service, ring, inflight, metrics)
                         .await;
@@ -350,39 +428,32 @@ where
         }
     });
 
-    let inv_transport = transport.clone();
+    if S::CACHES_RESPONSES {
-    let inv_service = service.clone();
+        let inv_transport = transport.clone();
-    tasks.spawn(async move {
+        let inv_service = service.clone();
-        loop {
+        let invalidate_prefix = format!("svc.{name}.invalidate.");
-            let mut sub = inv_transport.subscribe(&invalidate_subject).await?;
+        let invalidate_subject = format!("{invalidate_prefix}>");
-            info!(
+        tasks.spawn(async move {
-                subject = invalidate_subject,
-                "router listening for cache invalidations"
-            );
-
             loop {
-                tokio::select! {
+                let mut sub = inv_transport.subscribe(&invalidate_subject).await?;
-                    msg_opt = sub.next() => {
+                info!(
-                        let Some(msg) = msg_opt else {
+                    subject = invalidate_subject,
-                            warn!("router invalidation subscription stream ended, will re-subscribe");
+                    "router listening for cache invalidations"
-                            break;
+                );
-                        };
+
-                        let subject = msg.subject().to_owned();
+                while let Some(msg) = sub.next().await {
-                        let key = subject
+                    if let Some(key) = msg
-                            .strip_prefix(&format!("svc.{name}.invalidate."))
+                        .subject()
-                            .unwrap_or("");
+                        .strip_prefix(&invalidate_prefix)
-                        if !key.is_empty() {
+                        .filter(|key| !key.is_empty())
-                            inv_service.l1_invalidate(key);
+                    {
-                        }
+                        inv_service.l1_invalidate(key);
-                    }
-                    _ = inv_transport.wait_for_reconnect() => {
-                        info!("NATS reconnected, re-subscribing router invalidation listener");
-                        break;
                     }
                 }
+                warn!("router invalidation subscription stream ended, will re-subscribe");
             }
-        }
+        });
-    });
+    }
 
     tokio::select! {
         result = tasks.join_next() => {

fluxer_svc/src/shard.rs

@@ -1,11 +1,15 @@
 // SPDX-License-Identifier: AGPL-3.0-or-later
 
 use crate::config::ServiceConfig;
-use crate::metrics::{ServiceMetrics, now_ms};
+use crate::metrics::ServiceMetrics;
-use crate::transport::{Transport, TransportMessage, TransportSubscriber, reply_message};
+use crate::transport::{
+    Transport, TransportMessage, TransportSubscriber, reply_bytes, reply_json_error,
+};
+use anyhow::Context;
 use std::sync::Arc;
 use std::sync::atomic::{AtomicBool, Ordering};
-use tokio::sync::{Semaphore, TryAcquireError};
+use std::time::Instant;
+use tokio::sync::{Semaphore, TryAcquireError, oneshot};
 use tokio::task::JoinSet;
 use tracing::{debug, info, warn};
 
@@ -93,9 +97,14 @@ where
     let shard_is_serving = is_serving.clone();
     let shard_permits = request_permits.clone();
     let shard_metrics = metrics.clone();
-    tasks.spawn(async move {
+    let (stop_requests, mut stop_requests_rx) = oneshot::channel();
-        loop {
+    let request_task = tasks.spawn(async move {
-            let mut sub = shard_transport.subscribe(&shard_subject).await?;
+        let mut requests = JoinSet::new();
+        'listening: loop {
+            let mut sub = tokio::select! {
+                _ = &mut stop_requests_rx => break 'listening,
+                result = shard_transport.subscribe(&shard_subject) => result?,
+            };
             info!(
                 subject = shard_subject,
                 shard_id,
@@ -105,12 +114,23 @@ where
 
             loop {
                 tokio::select! {
+                    _ = &mut stop_requests_rx => break 'listening,
+                    result = requests.join_next(), if !requests.is_empty() => {
+                        if let Err(err) = result.expect("nonempty shard request set") {
+                            warn!(error = %err, "shard request task failed");
+                        }
+                    }
                     msg_opt = sub.next() => {
                         let Some(msg) = msg_opt else {
                             warn!("shard subscription stream ended, will re-subscribe");
                             break;
                         };
 
+                        while let Some(result) = requests.try_join_next() {
+                            if let Err(err) = result {
+                                warn!(error = %err, "shard request task failed");
+                            }
+                        }
                         if !shard_is_serving.load(Ordering::SeqCst) {
                             continue;
                         }
@@ -133,27 +153,25 @@ where
                                 debug!("shedding shard request, no permits available");
                                 shard_metrics.record_request();
                                 shard_metrics.record_request_error();
-                                reply_shard_error(&msg, &transport, "overloaded").await;
+                                reply_json_error(&msg, &transport, "overloaded").await;
                                 continue;
                             }
                             Err(TryAcquireError::Closed) => return anyhow::Ok(()),
                         };
-                        let raw_payload = msg.payload().to_vec();
+                        requests.spawn(async move {
-
-                        tokio::spawn(async move {
                             let _permit = permit;
                             if !is_serving.load(Ordering::SeqCst) {
                                 return;
                             }
-                            let request_start = now_ms();
+                            let request_start = Instant::now();
                             metrics.record_request();
-                            let encoding = WireEncoding::detect(&raw_payload);
+                            let encoding = WireEncoding::detect(msg.payload());
-                            let request: S::Request = match encoding.decode(&raw_payload) {
+                            let request: S::Request = match encoding.decode(msg.payload()) {
                                 Ok(r) => r,
                                 Err(err) => {
                                     warn!(error = %err, ?encoding, "failed to decode shard request");
                                     metrics.record_request_error();
-                                    reply_shard_error(&msg, &transport, "shard_request_decode_error")
+                                    reply_json_error(&msg, &transport, "shard_request_decode_error")
                                         .await;
                                     return;
                                 }
@@ -161,25 +179,20 @@ where
 
                             match service.handle(request).await {
                                 Ok(response) => {
-                                    let elapsed = (now_ms() - request_start).max(0) as u64;
+                                    metrics.record_request_duration(request_start.elapsed().as_millis() as u64);
-                                    metrics.record_request_duration(elapsed);
                                     if msg.has_reply() {
                                         match encoding.encode(&response) {
                                             Ok(response_bytes) => {
-                                                if let Err(err) =
+                                                reply_bytes(&msg, &transport, &response_bytes).await;
-                                                    reply_message(&msg, &transport, &response_bytes).await
-                                                {
-                                                    debug!(
-                                                        error = %err,
-                                                        "failed to send shard reply"
-                                                    );
-                                                }
                                             }
                                             Err(err) => {
                                                 warn!(
                                                     error = %err,
+                                                    ?encoding,
                                                     "failed to encode shard response"
                                                 );
+                                                metrics.record_request_error();
+                                                reply_json_error(&msg, &transport, "encode_error").await;
                                             }
                                         }
                                     }
@@ -187,20 +200,19 @@ where
                                 Err(err) => {
                                     warn!(error = %err, "shard handler returned error");
                                     metrics.record_request_error();
-                                    let elapsed = (now_ms() - request_start).max(0) as u64;
+                                    metrics.record_request_duration(request_start.elapsed().as_millis() as u64);
-                                    metrics.record_request_duration(elapsed);
+                                    reply_json_error(&msg, &transport, "shard_handler_error").await;
-                                    reply_shard_error(&msg, &transport, "shard_handler_error").await;
                                 }
                             }
                         });
                     }
-                    _ = shard_transport.wait_for_reconnect() => {
-                        info!("NATS reconnected, re-subscribing shard listener");
-                        break;
-                    }
                 }
             }
         }
+        while let Some(result) = requests.join_next().await {
+            result.context("shard request task failed while draining")?;
+        }
+        anyhow::Ok(())
     });
 
     tokio::select! {
@@ -217,20 +229,34 @@ where
 
             is_serving.store(false, Ordering::SeqCst);
 
-            let max_permits = config.max_concurrent_requests;
+            let _ = stop_requests.send(());
-            let drain_permits = request_permits.clone();
+            let drain = async {
-            crate::shutdown::drain_with_timeout(
+                loop {
-                async move {
+                    let (task_id, result) = tasks.join_next_with_id().await
-                    if let Ok(_permit) = drain_permits.acquire_many(max_permits as u32).await {
+                        .expect("running shard listener while draining")
-                        info!(
+                        .context("shard service task failed while draining")?;
-                            max_concurrent_requests = max_permits,
+                    result?;
-                            "all in-flight requests drained"
+                    if task_id == request_task.id() {
-                        );
+                        return anyhow::Ok(());
                     }
-                },
+                }
-                crate::shutdown::DEFAULT_DRAIN_TIMEOUT,
+            };
-            )
+            match tokio::time::timeout(crate::shutdown::DEFAULT_DRAIN_TIMEOUT, drain).await {
-            .await;
+                Ok(result) => {
+                    result?;
+                    info!(
+                        max_concurrent_requests = config.max_concurrent_requests,
+                        "all in-flight requests drained"
+                    );
+                    info!("graceful drain completed");
+                }
+                Err(_) => {
+                    warn!(
+                        timeout_secs = crate::shutdown::DEFAULT_DRAIN_TIMEOUT.as_secs(),
+                        "drain timeout exceeded, proceeding with shutdown"
+                    );
+                }
+            }
 
             info!("shard shutdown complete");
             Ok(())
@@ -238,16 +264,6 @@ where
     }
 }
 
-async fn reply_shard_error(msg: &impl TransportMessage, transport: &impl Transport, code: &str) {
-    if !msg.has_reply() {
-        return;
-    }
-    let response = serde_json::to_vec(&serde_json::json!({ "error": code })).unwrap_or_default();
-    if let Err(err) = reply_message(msg, transport, &response).await {
-        debug!(error = %err, "failed to send shard error reply");
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;

fluxer_svc/src/transport.rs

@@ -6,7 +6,7 @@ use std::sync::Arc;
 use std::sync::atomic::{AtomicU64, Ordering};
 use std::time::Duration;
 use tokio::sync::Notify;
-use tracing::{info, warn};
+use tracing::{debug, info, warn};
 
 const NATS_SUBSCRIPTION_CAPACITY: usize = 8_192;
 const SLOW_CONSUMER_LOG_INTERVAL_MS: u64 = 1_000;
@@ -62,6 +62,29 @@ where
     Ok(())
 }
 
+pub(crate) async fn reply_bytes(
+    message: &impl TransportMessage,
+    transport: &impl Transport,
+    payload: &[u8],
+) {
+    if let Err(error) = reply_message(message, transport, payload).await {
+        debug!(error = %error, subject = message.subject(), "failed to send service reply");
+    }
+}
+
+pub(crate) async fn reply_json_error(
+    message: &impl TransportMessage,
+    transport: &impl Transport,
+    code: &str,
+) {
+    if !message.has_reply() {
+        return;
+    }
+    let payload = serde_json::to_vec(&serde_json::json!({ "error": code }))
+        .expect("service error responses contain only a JSON-serializable string");
+    reply_bytes(message, transport, &payload).await;
+}
+
 #[derive(Clone)]
 pub struct NatsTransport {
     client: async_nats::Client,

fluxer_users/Cargo.toml

@@ -11,7 +11,7 @@ chrono = { version = "0.4", default-features = false }
 fluxer_common = { path = "../fluxer_common" }
 fluxer-svc = { path = "../fluxer_svc" }
 futures = "0.3.32"
-moka = { version = "0.12.15", features = ["future", "sync"] }
+moka = { version = "0.12.15", features = ["future"] }
 rmp-serde = "1.3"
 scylla = { version = "1.6.0", features = ["chrono-04"], optional = true }
 serde = { version = "1.0.228", features = ["derive"] }

fluxer_users/src/main.rs

@@ -26,10 +26,7 @@ async fn main() -> anyhow::Result<()> {
     );
 
     match config.mode {
-        Mode::Router => {
+        Mode::Router => fluxer_svc::router::run_router(&config, UsersRouter, transport).await,
-            let router = UsersRouter::new(config.cache_max_entries, config.cache_ttl);
-            fluxer_svc::router::run_router(&config, router, transport).await
-        }
         Mode::Shard => {
             let shard = match config.database_backend {
                 DatabaseBackend::Postgres => {
@@ -37,12 +34,7 @@ async fn main() -> anyhow::Result<()> {
                         fluxer_svc::postgres::PostgresConfig::from_service_config(&config);
                     let pool = fluxer_svc::postgres::connect(&postgres_config).await?;
                     let kv = fluxer_svc::postgres::KvClient::new(pool, &postgres_config)?;
-                    UsersShard::new_postgres(
+                    UsersShard::new_postgres(kv, config.cache_max_entries, config.cache_ttl)
-                        kv,
-                        transport.clone(),
-                        config.cache_max_entries,
-                        config.cache_ttl,
-                    )?
                 }
                 DatabaseBackend::Cassandra => {
                     #[cfg(feature = "scylla")]
@@ -50,13 +42,8 @@ async fn main() -> anyhow::Result<()> {
                         let scylla_config =
                             fluxer_svc::scylla::ScyllaConfig::from_service_config(&config);
                         let db = fluxer_svc::scylla::connect(&scylla_config).await?;
-                        UsersShard::new_scylla(
+                        UsersShard::new_scylla(db, config.cache_max_entries, config.cache_ttl)
-                            db,
+                            .await?
-                            transport.clone(),
-                            config.cache_max_entries,
-                            config.cache_ttl,
-                        )
-                        .await?
                     }
                     #[cfg(not(feature = "scylla"))]
                     {

fluxer_users/src/router_impl.rs

@@ -2,36 +2,24 @@
 
 use crate::types::{UserRequest, UserResponse};
 use fluxer_svc::router::RouterService;
-use moka::sync::Cache;
-use std::time::Duration;
 
-pub struct UsersRouter {
+pub struct UsersRouter;
-    l1: Cache<String, UserResponse>,
-}
-
-impl UsersRouter {
-    pub fn new(max_entries: u64, ttl: Duration) -> Self {
-        Self {
-            l1: Cache::builder()
-                .max_capacity(max_entries)
-                .time_to_live(ttl)
-                .build(),
-        }
-    }
-}
 
 impl RouterService for UsersRouter {
     type Request = UserRequest;
     type Response = UserResponse;
 
+    const CACHES_RESPONSES: bool = false;
+
     fn service_name(&self) -> &str {
         "users"
     }
 
     fn route_key(req: &UserRequest) -> String {
         match req {
-            UserRequest::GetById { user_id } => user_id.to_string(),
+            UserRequest::GetById { user_id }
-            UserRequest::GetPartialById { user_id } => user_id.to_string(),
+            | UserRequest::GetPartialById { user_id }
+            | UserRequest::Invalidate { user_id } => user_id.to_string(),
             UserRequest::GetPartialsByIds { user_ids } => user_ids
                 .iter()
                 .min()
@@ -43,7 +31,6 @@ impl RouterService for UsersRouter {
                 .min()
                 .cloned()
                 .unwrap_or_else(|| "0".to_owned()),
-            UserRequest::Invalidate { user_id } => user_id.to_string(),
         }
     }
 
@@ -74,117 +61,12 @@ impl RouterService for UsersRouter {
         }
     }
 
-    fn l1_lookup(&self, req: &UserRequest) -> Option<UserResponse> {
+    fn is_broadcast_request(req: &UserRequest) -> bool {
-        match req {
+        matches!(req, UserRequest::Invalidate { .. })
-            UserRequest::GetById { user_id } => self.l1.get(&user_id.to_string()),
-            UserRequest::GetPartialById { user_id } => {
-                let cached = self.l1.get(&user_id.to_string())?;
-                match cached {
-                    UserResponse::Found(ref user) => {
-                        Some(UserResponse::FoundPartial(user.to_partial()))
-                    }
-                    UserResponse::FoundPartial(_) => Some(cached),
-                    UserResponse::NotFound => Some(UserResponse::NotFound),
-                    _ => None,
-                }
-            }
-            UserRequest::GetPartialsByIds { user_ids } => {
-                let mut partials = Vec::with_capacity(user_ids.len());
-                for user_id in user_ids {
-                    let cached = self.l1.get(&user_id.to_string())?;
-                    match cached {
-                        UserResponse::Found(ref user) => partials.push(user.to_partial()),
-                        UserResponse::FoundPartial(partial) => partials.push(partial),
-                        UserResponse::NotFound => {}
-                        _ => return None,
-                    }
-                }
-                Some(UserResponse::FoundPartials(partials))
-            }
-            UserRequest::GetApiPartialById { user_id } => {
-                let cached = self.l1.get(user_id)?;
-                match cached {
-                    UserResponse::Found(ref user) => {
-                        Some(UserResponse::FoundApiPartial(user.to_api_partial()))
-                    }
-                    UserResponse::FoundPartial(ref partial) => {
-                        Some(UserResponse::FoundApiPartial(partial.to_api_partial()))
-                    }
-                    UserResponse::FoundApiPartial(partial) => {
-                        Some(UserResponse::FoundApiPartial(partial))
-                    }
-                    UserResponse::NotFound => Some(UserResponse::NotFound),
-                    _ => None,
-                }
-            }
-            UserRequest::GetApiPartialsByIds { user_ids } => {
-                let mut partials = Vec::with_capacity(user_ids.len());
-                for user_id in user_ids {
-                    let cached = self.l1.get(user_id)?;
-                    match cached {
-                        UserResponse::Found(ref user) => partials.push(user.to_api_partial()),
-                        UserResponse::FoundPartial(ref partial) => {
-                            partials.push(partial.to_api_partial())
-                        }
-                        UserResponse::FoundApiPartial(partial) => partials.push(partial),
-                        UserResponse::NotFound => {}
-                        _ => return None,
-                    }
-                }
-                Some(UserResponse::FoundApiPartials(partials))
-            }
-            UserRequest::Invalidate { .. } => None,
-        }
     }
 
-    fn l1_insert(&self, req: &UserRequest, resp: &UserResponse) {
+    fn is_broadcast_acknowledgement(response: &UserResponse) -> bool {
-        match req {
+        matches!(response, UserResponse::Invalidated)
-            UserRequest::GetById { user_id } => {
-                self.l1.insert(user_id.to_string(), resp.clone());
-            }
-            UserRequest::GetPartialById { user_id } => {
-                if !matches!(
-                    self.l1.get(&user_id.to_string()),
-                    Some(UserResponse::Found(_))
-                ) {
-                    self.l1.insert(user_id.to_string(), resp.clone());
-                }
-            }
-            UserRequest::GetPartialsByIds { .. } => {
-                if let UserResponse::FoundPartials(partials) = resp {
-                    for partial in partials {
-                        let key = partial.user_id.to_string();
-                        if !matches!(self.l1.get(&key), Some(UserResponse::Found(_))) {
-                            self.l1
-                                .insert(key, UserResponse::FoundPartial(partial.clone()));
-                        }
-                    }
-                }
-            }
-            UserRequest::GetApiPartialById { .. } => {
-                if let UserResponse::FoundApiPartial(partial) = resp {
-                    self.l1.insert(
-                        partial.id.clone(),
-                        UserResponse::FoundApiPartial(partial.clone()),
-                    );
-                }
-            }
-            UserRequest::GetApiPartialsByIds { .. } => {
-                if let UserResponse::FoundApiPartials(partials) = resp {
-                    for partial in partials {
-                        self.l1.insert(
-                            partial.id.clone(),
-                            UserResponse::FoundApiPartial(partial.clone()),
-                        );
-                    }
-                }
-            }
-            UserRequest::Invalidate { .. } => {}
-        }
-    }
-
-    fn l1_invalidate(&self, key: &str) {
-        self.l1.invalidate(key);
     }
 }
 
@@ -192,72 +74,39 @@ impl RouterService for UsersRouter {
 mod tests {
     use super::*;
 
-    fn api_partial(id: &str) -> crate::types::ApiUserPartial {
+    #[test]
-        crate::types::ApiUserPartial {
+    fn coalesce_key_ignores_batch_id_order() {
-            id: id.to_owned(),
+        let forward = UserRequest::GetPartialsByIds {
-            username: "Ada".to_owned(),
+            user_ids: vec![7, 42, 7],
-            discriminator: "0007".to_owned(),
+        };
-            global_name: Some("Ada Lovelace".to_owned()),
+        let reversed = UserRequest::GetPartialsByIds {
-            avatar: Some("avatar_hash".to_owned()),
+            user_ids: vec![42, 7],
-            avatar_color: Some(0x336699),
+        };
-            bot: None,
+        assert_eq!(
-            system: None,
+            UsersRouter::coalesce_key(&forward),
-            flags: 1,
+            UsersRouter::coalesce_key(&reversed)
-            mention_flags: None,
+        );
-        }
     }
 
     #[test]
-    fn l1_caches_api_partial_batch_responses() {
+    fn coalesce_key_separates_batches_with_different_ids() {
-        let router = UsersRouter::new(100, Duration::from_secs(30));
+        let left = UserRequest::GetApiPartialsByIds {
-        let partial = api_partial("9223372036854775807");
+            user_ids: vec!["7".to_owned(), "42".to_owned()],
-        router.l1_insert(
+        };
-            &UserRequest::GetApiPartialsByIds {
+        let right = UserRequest::GetApiPartialsByIds {
-                user_ids: vec![partial.id.clone()],
+            user_ids: vec!["7".to_owned()],
-            },
+        };
-            &UserResponse::FoundApiPartials(vec![partial.clone()]),
+        assert_ne!(
+            UsersRouter::coalesce_key(&left),
+            UsersRouter::coalesce_key(&right)
         );
-
-        let cached = router.l1_lookup(&UserRequest::GetApiPartialsByIds {
-            user_ids: vec![partial.id.clone()],
-        });
-
-        match cached {
-            Some(UserResponse::FoundApiPartials(partials)) => {
-                assert_eq!(partials.len(), 1);
-                assert_eq!(partials[0].id, partial.id);
-                assert_eq!(partials[0].username, partial.username);
-            }
-            other => panic!("unexpected cached response: {other:?}"),
-        }
     }
 
     #[test]
-    fn l1_invalidates_cached_api_partials_by_user_id() {
+    fn invalidations_are_never_coalesced() {
-        let router = UsersRouter::new(100, Duration::from_secs(30));
+        assert_eq!(
-        let partial = api_partial("42");
+            UsersRouter::coalesce_key(&UserRequest::Invalidate { user_id: 42 }),
-        router.l1_insert(
+            None
-            &UserRequest::GetApiPartialById {
-                user_id: partial.id.clone(),
-            },
-            &UserResponse::FoundApiPartial(partial.clone()),
-        );
-
-        assert!(
-            router
-                .l1_lookup(&UserRequest::GetApiPartialById {
-                    user_id: partial.id.clone(),
-                })
-                .is_some()
-        );
-        router.l1_invalidate(&partial.id);
-
-        assert!(
-            router
-                .l1_lookup(&UserRequest::GetApiPartialById {
-                    user_id: partial.id,
-                })
-                .is_none()
         );
     }
 }

fluxer_users/src/shard_impl.rs

@@ -4,7 +4,6 @@ use crate::types::{ApiUserPartial, User, UserPartial, UserRequest, UserResponse}
 #[cfg(feature = "scylla")]
 use chrono::{DateTime, NaiveDate, Utc};
 use fluxer_svc::shard::ShardService;
-use fluxer_svc::transport::NatsTransport;
 use fluxer_svc::{postgres, postgres::KeyPart};
 use futures::stream::{self, StreamExt};
 use moka::future::Cache;
@@ -17,8 +16,12 @@ use scylla::statement::prepared::PreparedStatement;
 #[cfg(feature = "scylla")]
 use scylla::value::MaybeEmpty;
 use serde::Deserialize;
+use std::collections::{HashMap, hash_map::DefaultHasher};
+use std::fmt::Write;
 use std::future::Future;
+use std::hash::{Hash, Hasher};
 use std::sync::Arc;
+use std::sync::atomic::{AtomicU64, Ordering};
 use std::time::Duration;
 
 #[cfg(feature = "scylla")]
@@ -60,6 +63,8 @@ const PARTIAL_USER_COLUMNS: &str = "\
     mention_flags";
 const USER_BATCH_SIZE: usize = 128;
 const USER_BATCH_CONCURRENCY: usize = 8;
+const USER_CACHE_MIN_GENERATION_STRIPES: usize = 4096;
+const USER_CACHE_MAX_GENERATION_STRIPES: usize = 1 << 20;
 const FLUXER_SYSTEM_USER_ID: i64 = 0;
 const FLUXER_SYSTEM_USERNAME: &str = "Fluxer";
 const FLUXER_SYSTEM_DISCRIMINATOR: i32 = 0;
@@ -68,12 +73,19 @@ const USER_FLAG_STAFF: i64 = 1;
 pub struct UsersShard {
     storage: UsersStorage,
     caches: UserCaches,
-    transport: NatsTransport,
 }
 
 struct UserCaches {
-    full: Cache<i64, Option<User>>,
+    full: Cache<UserCacheKey, Option<User>>,
-    partial: Cache<i64, Option<UserPartial>>,
+    partial: Cache<UserCacheKey, Option<UserPartial>>,
+    generations: Box<[AtomicU64]>,
+    generation_bumps: AtomicU64,
+}
+
+#[derive(Clone, Copy, Eq, Hash, PartialEq)]
+struct UserCacheKey {
+    user_id: i64,
+    generation: u64,
 }
 
 #[derive(Clone)]
@@ -159,26 +171,9 @@ struct FullUserDbRow {
     timezone_privacy_flags: Option<i32>,
 }
 
-#[cfg(feature = "scylla")]
-#[derive(Debug, DeserializeRow)]
-struct PartialUserDbRow {
-    user_id: i64,
-    username: String,
-    discriminator: i32,
-    global_name: Option<String>,
-    avatar_hash: Option<String>,
-    bot: Option<bool>,
-    system: Option<bool>,
-    flags: Option<i64>,
-    banner_hash: Option<String>,
-    banner_color: Option<i32>,
-    accent_color: Option<i32>,
-    avatar_color: Option<i32>,
-    mention_flags: Option<i32>,
-}
-
 #[derive(Debug, Deserialize)]
-struct PartialUserKvRow {
+#[cfg_attr(feature = "scylla", derive(DeserializeRow))]
+struct PartialUserDbRow {
     user_id: i64,
     username: String,
     discriminator: i32,
@@ -256,6 +251,16 @@ struct FullUserKvRow {
     timezone_privacy_flags: Option<i32>,
 }
 
+fn generation_stripes(max_entries: u64) -> usize {
+    usize::try_from(max_entries)
+        .unwrap_or(USER_CACHE_MAX_GENERATION_STRIPES)
+        .clamp(
+            USER_CACHE_MIN_GENERATION_STRIPES,
+            USER_CACHE_MAX_GENERATION_STRIPES,
+        )
+        .next_power_of_two()
+}
+
 impl UserCaches {
     fn new(max_entries: u64, ttl: Duration) -> Self {
         Self {
@@ -267,6 +272,23 @@ impl UserCaches {
                 .max_capacity(max_entries)
                 .time_to_live(ttl)
                 .build(),
+            generations: (0..generation_stripes(max_entries))
+                .map(|_| AtomicU64::new(0))
+                .collect(),
+            generation_bumps: AtomicU64::new(0),
+        }
+    }
+
+    fn generation(&self, user_id: i64) -> &AtomicU64 {
+        let mut hasher = DefaultHasher::new();
+        user_id.hash(&mut hasher);
+        &self.generations[hasher.finish() as usize % self.generations.len()]
+    }
+
+    fn key(&self, user_id: i64) -> UserCacheKey {
+        UserCacheKey {
+            user_id,
+            generation: self.generation(user_id).load(Ordering::SeqCst),
         }
     }
 
@@ -274,13 +296,14 @@ impl UserCaches {
     where
         F: Future<Output = anyhow::Result<Option<User>>>,
     {
+        let key = self.key(user_id);
         let user = self
             .full
-            .try_get_with(user_id, fetch)
+            .try_get_with(key, fetch)
             .await
             .map_err(|e: Arc<anyhow::Error>| anyhow::anyhow!("{e}"))?;
         self.partial
-            .insert(user_id, user.as_ref().map(User::to_partial))
+            .insert(key, user.as_ref().map(User::to_partial))
             .await;
         Ok(user)
     }
@@ -294,43 +317,47 @@ impl UserCaches {
         F: Future<Output = anyhow::Result<Option<UserPartial>>>,
     {
         self.partial
-            .try_get_with(user_id, fetch)
+            .try_get_with(self.key(user_id), fetch)
             .await
             .map_err(|e: Arc<anyhow::Error>| anyhow::anyhow!("{e}"))
     }
 
     async fn get_partial(&self, user_id: i64) -> Option<Option<UserPartial>> {
-        self.partial.get(&user_id).await
+        self.partial.get(&self.key(user_id)).await
     }
 
-    async fn insert_partial(&self, user_id: i64, partial: Option<UserPartial>) {
+    async fn insert_partial(&self, key: UserCacheKey, partial: Option<UserPartial>) {
-        self.partial.insert(user_id, partial).await;
+        self.partial.insert(key, partial).await;
     }
 
     async fn invalidate(&self, user_id: i64) {
-        self.full.invalidate(&user_id).await;
+        let generation = self
-        self.partial.invalidate(&user_id).await;
+            .generation(user_id)
+            .fetch_update(Ordering::SeqCst, Ordering::SeqCst, |current| {
+                current.checked_add(1)
+            })
+            .expect("user cache generation exhausted");
+        self.generation_bumps.fetch_add(1, Ordering::Relaxed);
+        let key = UserCacheKey {
+            user_id,
+            generation,
+        };
+        self.full.invalidate(&key).await;
+        self.partial.invalidate(&key).await;
     }
 }
 
 impl UsersShard {
-    pub fn new_postgres(
+    pub fn new_postgres(kv: postgres::KvClient, max_entries: u64, ttl: Duration) -> Self {
-        kv: postgres::KvClient,
+        Self {
-        transport: NatsTransport,
-        max_entries: u64,
-        ttl: Duration,
-    ) -> anyhow::Result<Self> {
-        Ok(Self {
             storage: UsersStorage::Postgres(PostgresUsersStorage { kv }),
             caches: UserCaches::new(max_entries, ttl),
-            transport,
+        }
-        })
     }
 
     #[cfg(feature = "scylla")]
     pub async fn new_scylla(
         db: Arc<Session>,
-        transport: NatsTransport,
         max_entries: u64,
         ttl: Duration,
     ) -> anyhow::Result<Self> {
@@ -358,7 +385,6 @@ impl UsersShard {
                 stmt_partial_batch,
             })),
             caches: UserCaches::new(max_entries, ttl),
-            transport,
         })
     }
 
@@ -366,12 +392,8 @@ impl UsersShard {
         if user_id == FLUXER_SYSTEM_USER_ID {
             return Ok(Some(fluxer_system_user()));
         }
-        let storage = self.storage.clone();
         self.caches
-            .get_or_fetch_full(
+            .get_or_fetch_full(user_id, self.storage.fetch_full_user(user_id))
-                user_id,
-                async move { storage.fetch_full_user(user_id).await },
-            )
             .await
     }
 
@@ -379,17 +401,12 @@ impl UsersShard {
         if user_id == FLUXER_SYSTEM_USER_ID {
             return Ok(Some(fluxer_system_user().to_partial()));
         }
-        let storage = self.storage.clone();
         self.caches
-            .get_or_fetch_partial(
+            .get_or_fetch_partial(user_id, self.storage.fetch_partial_user(user_id))
-                user_id,
-                async move { storage.fetch_partial_user(user_id).await },
-            )
             .await
     }
 
-    async fn get_partial_users(&self, user_ids: Vec<i64>) -> anyhow::Result<Vec<UserPartial>> {
+    async fn get_partial_users(&self, mut user_ids: Vec<i64>) -> anyhow::Result<Vec<UserPartial>> {
-        let mut user_ids = user_ids;
         user_ids.sort_unstable();
         user_ids.dedup();
         let mut partials = Vec::new();
@@ -451,43 +468,40 @@ impl UsersShard {
     }
 
     async fn fetch_partial_batch(&self, user_ids: Vec<i64>) -> anyhow::Result<Vec<UserPartial>> {
-        let mut partials = Vec::new();
+        let mut cache_keys = user_ids
-        let user_ids = user_ids
+            .iter()
-            .into_iter()
+            .map(|&user_id| (user_id, self.caches.key(user_id)))
-            .filter(|user_id| {
+            .collect::<HashMap<_, _>>();
-                if *user_id == FLUXER_SYSTEM_USER_ID {
-                    partials.push(fluxer_system_user().to_partial());
-                    false
-                } else {
-                    true
-                }
-            })
-            .collect::<Vec<_>>();
-        if user_ids.is_empty() {
-            return Ok(partials);
-        }
         let fetched_partials = match self.storage.fetch_partial_batch(user_ids.clone()).await {
-            Ok(partials) => partials,
+            Ok(fetched) => fetched,
-            Err(_) => {
+            Err(err) => {
-                partials.extend(self.fetch_partial_batch_individually(user_ids).await?);
+                tracing::warn!(
-                return Ok(partials);
+                    error = %err,
+                    user_count = user_ids.len(),
+                    "user partial batch read failed, retrying per user"
+                );
+                return self.fetch_partial_batch_individually(user_ids).await;
             }
         };
-        let found_ids = fetched_partials
+        let mut unexpected = 0usize;
-            .iter()
+        let mut partials = Vec::with_capacity(fetched_partials.len());
-            .map(|partial| partial.user_id)
+        for partial in fetched_partials {
-            .collect::<std::collections::HashSet<_>>();
+            let Some(key) = cache_keys.remove(&partial.user_id) else {
-        for partial in &fetched_partials {
+                unexpected += 1;
-            self.caches
+                continue;
-                .insert_partial(partial.user_id, Some(partial.clone()))
+            };
-                .await;
+            self.caches.insert_partial(key, Some(partial.clone())).await;
+            partials.push(partial);
         }
-        for user_id in user_ids {
+        if unexpected > 0 {
-            if !found_ids.contains(&user_id) {
+            tracing::warn!(
-                self.caches.insert_partial(user_id, None).await;
+                unexpected,
-            }
+                "user batch returned duplicate or unrequested users"
+            );
+        }
+        for key in cache_keys.into_values() {
+            self.caches.insert_partial(key, None).await;
         }
-        partials.extend(fetched_partials);
         Ok(partials)
     }
 
@@ -603,7 +617,7 @@ fn decode_postgres_user(row: serde_json::Value) -> anyhow::Result<User> {
 
 fn decode_postgres_user_partial(row: serde_json::Value) -> anyhow::Result<UserPartial> {
     let row = postgres::decode_row_dates_as_millis(row)?;
-    let row: PartialUserKvRow = serde_json::from_value(row)?;
+    let row: PartialUserDbRow = serde_json::from_value(row)?;
     Ok(row.into())
 }
 
@@ -678,34 +692,49 @@ impl ShardService for UsersShard {
         "users"
     }
 
+    fn render_prometheus_metrics(&self, output: &mut String) {
+        let _ = writeln!(
+            output,
+            "# TYPE fluxer_users_shard_cache_generation_bumps_total counter"
+        );
+        let _ = writeln!(
+            output,
+            "fluxer_users_shard_cache_generation_bumps_total {}",
+            self.caches.generation_bumps.load(Ordering::Relaxed)
+        );
+        let _ = writeln!(
+            output,
+            "# TYPE fluxer_users_shard_cache_generation_stripes gauge"
+        );
+        let _ = writeln!(
+            output,
+            "fluxer_users_shard_cache_generation_stripes {}",
+            self.caches.generations.len()
+        );
+    }
+
     async fn handle(&self, request: UserRequest) -> anyhow::Result<UserResponse> {
         match request {
-            UserRequest::GetById { user_id } => match self.get_full_user(user_id).await? {
+            UserRequest::GetById { user_id } => Ok(self
-                Some(user) => Ok(UserResponse::Found(user)),
+                .get_full_user(user_id)
-                None => Ok(UserResponse::NotFound),
+                .await?
-            },
+                .map_or(UserResponse::NotFound, UserResponse::Found)),
-            UserRequest::GetPartialById { user_id } => {
+            UserRequest::GetPartialById { user_id } => Ok(self
-                match self.get_partial_user(user_id).await? {
+                .get_partial_user(user_id)
-                    Some(partial) => Ok(UserResponse::FoundPartial(partial)),
+                .await?
-                    None => Ok(UserResponse::NotFound),
+                .map_or(UserResponse::NotFound, UserResponse::FoundPartial)),
-                }
-            }
             UserRequest::GetPartialsByIds { user_ids } => Ok(UserResponse::FoundPartials(
                 self.get_partial_users(user_ids).await?,
             )),
-            UserRequest::GetApiPartialById { user_id } => {
+            UserRequest::GetApiPartialById { user_id } => Ok(self
-                match self.get_api_partial_user(user_id).await? {
+                .get_api_partial_user(user_id)
-                    Some(partial) => Ok(UserResponse::FoundApiPartial(partial)),
+                .await?
-                    None => Ok(UserResponse::NotFound),
+                .map_or(UserResponse::NotFound, UserResponse::FoundApiPartial)),
-                }
-            }
             UserRequest::GetApiPartialsByIds { user_ids } => Ok(UserResponse::FoundApiPartials(
                 self.get_api_partial_users(user_ids).await?,
             )),
             UserRequest::Invalidate { user_id } => {
                 self.caches.invalidate(user_id).await;
-                let subject = format!("svc.users.invalidate.{user_id}");
-                self.transport.publish(&subject, &[]).await?;
                 Ok(UserResponse::Invalidated)
             }
         }
@@ -734,7 +763,6 @@ fn optional_date_string(value: OptionalDate) -> Option<String> {
     })
 }
 
-#[cfg(feature = "scylla")]
 impl From<PartialUserDbRow> for UserPartial {
     fn from(row: PartialUserDbRow) -> Self {
         Self {
@@ -755,26 +783,6 @@ impl From<PartialUserDbRow> for UserPartial {
     }
 }
 
-impl From<PartialUserKvRow> for UserPartial {
-    fn from(row: PartialUserKvRow) -> Self {
-        Self {
-            user_id: row.user_id,
-            username: row.username,
-            discriminator: row.discriminator,
-            global_name: row.global_name,
-            avatar_hash: row.avatar_hash,
-            bot: row.bot,
-            system: row.system,
-            flags: row.flags,
-            banner_hash: row.banner_hash,
-            banner_color: row.banner_color,
-            accent_color: row.accent_color,
-            avatar_color: row.avatar_color,
-            mention_flags: row.mention_flags,
-        }
-    }
-}
-
 #[cfg(feature = "scylla")]
 impl From<FullUserDbRow> for User {
     fn from(row: FullUserDbRow) -> Self {
@@ -967,7 +975,7 @@ mod tests {
             caches.get_partial(42).await.unwrap().unwrap().username,
             "Ada"
         );
-        assert!(caches.full.get(&42).await.is_none());
+        assert!(caches.full.get(&caches.key(42)).await.is_none());
     }
 
     #[tokio::test]
@@ -1001,7 +1009,14 @@ mod tests {
 
         assert_eq!(fetched.email.as_deref(), Some("[email protected]"));
         assert_eq!(
-            caches.full.get(&42).await.unwrap().unwrap().bio.as_deref(),
+            caches
+                .full
+                .get(&caches.key(42))
+                .await
+                .unwrap()
+                .unwrap()
+                .bio
+                .as_deref(),
             Some("analytical engine enjoyer")
         );
         let cached_partial = caches.get_partial(42).await.unwrap().unwrap();
@@ -1019,7 +1034,7 @@ mod tests {
             .unwrap();
 
         assert!(fetched.is_none());
-        assert!(matches!(caches.full.get(&42).await, Some(None)));
+        assert!(matches!(caches.full.get(&caches.key(42)).await, Some(None)));
         assert!(matches!(caches.get_partial(42).await, Some(None)));
     }
 
@@ -1030,12 +1045,12 @@ mod tests {
             .get_or_fetch_full(42, async { Ok(Some(test_user(42))) })
             .await
             .unwrap();
-        assert!(caches.full.get(&42).await.is_some());
+        assert!(caches.full.get(&caches.key(42)).await.is_some());
         assert!(caches.get_partial(42).await.is_some());
 
         caches.invalidate(42).await;
 
-        assert!(caches.full.get(&42).await.is_none());
+        assert!(caches.full.get(&caches.key(42)).await.is_none());
         assert!(caches.get_partial(42).await.is_none());
     }
 
@@ -1052,6 +1067,27 @@ mod tests {
         assert!(caches.get_partial(42).await.is_none());
     }
 
+    #[tokio::test]
+    async fn invalidation_counts_generation_bumps() {
+        let caches = caches();
+        assert_eq!(caches.generation_bumps.load(Ordering::Relaxed), 0);
+
+        caches.invalidate(42).await;
+        caches.invalidate(43).await;
+
+        assert_eq!(caches.generation_bumps.load(Ordering::Relaxed), 2);
+    }
+
+    #[test]
+    fn generation_stripes_follow_the_configured_capacity() {
+        assert_eq!(generation_stripes(16), USER_CACHE_MIN_GENERATION_STRIPES);
+        assert_eq!(generation_stripes(100_000), 131_072);
+        assert_eq!(
+            generation_stripes(u64::MAX),
+            USER_CACHE_MAX_GENERATION_STRIPES
+        );
+    }
+
     #[cfg(feature = "scylla")]
     #[test]
     fn partial_columns_match_the_user_partial_fields_exactly() {

fluxer_users/src/types.rs

@@ -159,24 +159,6 @@ impl User {
             mention_flags: self.mention_flags,
         }
     }
-
-    pub fn to_api_partial(&self) -> ApiUserPartial {
-        if self.user_id == FLUXER_SYSTEM_USER_ID {
-            return fluxer_system_user();
-        }
-        ApiUserPartial {
-            id: self.user_id.to_string(),
-            username: self.username.clone(),
-            discriminator: format!("{:04}", self.discriminator),
-            global_name: self.global_name.clone(),
-            avatar: self.avatar_hash.clone(),
-            avatar_color: self.avatar_color,
-            bot: self.bot.filter(|bot| *bot),
-            system: self.system.filter(|system| *system),
-            flags: visible_user_flags(self.flags.unwrap_or_default()),
-            mention_flags: self.mention_flags.filter(|flags| *flags != 0),
-        }
-    }
 }
 
 impl UserPartial {
@@ -320,30 +302,10 @@ mod tests {
     }
 
     #[test]
-    fn direct_api_partial_matches_the_two_step_conversion() {
+    fn api_partial_ignores_fields_outside_the_partial() {
-        for user_id in [123, FLUXER_SYSTEM_USER_ID] {
-            for flags in [
-                0,
-                USER_FLAG_STAFF,
-                USER_FLAG_STAFF | USER_FLAG_STAFF_HIDDEN | USER_FLAG_PARTNER,
-                USER_FLAG_DELETED,
-            ] {
-                let user = user_with_flags(user_id, flags);
-
-                assert_eq!(
-                    serde_json::to_value(user.to_api_partial()).unwrap(),
-                    serde_json::to_value(user.to_partial().to_api_partial()).unwrap(),
-                    "user_id {user_id} flags {flags}"
-                );
-            }
-        }
-    }
-
-    #[test]
-    fn direct_api_partial_ignores_fields_outside_the_partial() {
         let mut user = user_with_flags(123, USER_FLAG_STAFF);
         user.mention_flags = Some(0);
-        let api_partial = user.to_api_partial();
+        let api_partial = user.to_partial().to_api_partial();
 
         assert_eq!(api_partial.id, "123");
         assert_eq!(api_partial.username, "Ada");

knip.json

@@ -12,7 +12,12 @@
 		"tailwindcss",
 		"upng-js"
 	],
-	"ignoreFiles": ["fluxer_admin/src/styles/app.css", "fluxer_admin/static/htmx.min.js"],
+	"ignoreFiles": [
+		"fluxer_admin/src/styles/app.css",
+		"fluxer_admin/static/htmx.min.js",
+		"tools/ci/templates/libfluxcore_wrapper.d.ts",
+		"tools/ci/templates/libfluxcore_wrapper.js"
+	],
 	"ignoreIssues": {
 		"fluxer_app/scripts/build/Config.tsx": ["exports"],
 		"fluxer_app/scripts/build/rspack/static-files.mjs": ["exports"],
@@ -30,8 +35,7 @@
 	},
 	"workspaces": {
 		".": {
-			"ignoreDependencies": ["vite"],
+			"ignoreDependencies": ["vite"]
-			"project": ["scripts/**/*.mjs"]
 		},
 		"fluxer_api": {
 			"ignoreDependencies": [

package.json

@@ -37,7 +37,6 @@
 		"lint": "cargo run -p fluxer-dev -- lint",
 		"openapi:generate": "pnpm --filter @fluxer/openapi generate",
 		"openapi:validate": "pnpm --filter @fluxer/openapi validate",
-		"remote": "node scripts/remote.mjs",
 		"test": "cargo run -p fluxer-dev -- test",
 		"typecheck": "cargo run -p fluxer-dev -- typecheck"
 	},

pnpm-lock.yaml

@@ -87,6 +87,9 @@ catalogs:
     '@marsidev/react-turnstile':
       specifier: 1.4.2
       version: 1.4.2
+    '@mdx-js/mdx':
+      specifier: 3.1.1
+      version: 3.1.1
     '@messageformat/core':
       specifier: 3.4.0
       version: 3.4.0
@@ -138,6 +141,9 @@ catalogs:
     '@types/luxon':
       specifier: 3.7.1
       version: 3.7.1
+    '@types/mdast':
+      specifier: 4.0.4
+      version: 4.0.4
     '@types/node':
       specifier: 25.3.0
       version: 25.3.0
@@ -279,6 +285,9 @@ catalogs:
     maxmind:
       specifier: 5.0.5
       version: 5.0.5
+    mdast-util-mdx-jsx:
+      specifier: 3.2.0
+      version: 3.2.0
     mdast-util-to-hast:
       specifier: 13.2.1
       version: 13.2.1
@@ -363,6 +372,9 @@ catalogs:
     react-hotkeys-hook:
       specifier: 5.2.4
       version: 5.2.4
+    remark-gfm:
+      specifier: 4.0.1
+      version: 4.0.1
     rxjs:
       specifier: 7.8.2
       version: 7.8.2
@@ -411,6 +423,9 @@ catalogs:
     undici:
       specifier: 7.29.0
       version: 7.29.0
+    undici-types:
+      specifier: 7.18.2
+      version: 7.18.2
     unique-names-generator:
       specifier: 4.7.1
       version: 4.7.1
@@ -597,9 +612,6 @@ importers:
       '@pkgs/http_client':
         specifier: workspace:*
         version: link:pkgs/http_client
-      '@pkgs/initialization':
-        specifier: workspace:*
-        version: link:pkgs/initialization
       '@pkgs/kv_client':
         specifier: workspace:*
         version: link:pkgs/kv_client
@@ -887,19 +899,13 @@ importers:
       '@typescript/native-preview':
         specifier: 'catalog:'
         version: 7.0.0-dev.20260224.1
+      undici-types:
+        specifier: 'catalog:'
+        version: 7.18.2
       vitest:
         specifier: 'catalog:'
         version: 4.1.11(@opentelemetry/[email protected])(@types/[email protected])(@vitest/[email protected])([email protected])([email protected](@noble/[email protected]))([email protected](@types/[email protected])([email protected]))([email protected](@types/[email protected])([email protected])([email protected])([email protected])([email protected]))
 
-  fluxer_api/pkgs/initialization:
-    devDependencies:
-      '@types/node':
-        specifier: 'catalog:'
-        version: 25.3.0
-      '@typescript/native-preview':
-        specifier: 'catalog:'
-        version: 7.0.0-dev.20260224.1
-
   fluxer_api/pkgs/kv_client:
     dependencies:
       '@fluxer/constants':
@@ -1919,18 +1925,30 @@ importers:
       '@fluxer/openapi':
         specifier: workspace:*
         version: link:../packages/openapi
+      '@mdx-js/mdx':
+        specifier: 'catalog:'
+        version: 3.1.1
       '@types/hast':
         specifier: 'catalog:'
         version: 3.0.5
+      '@types/mdast':
+        specifier: 'catalog:'
+        version: 4.0.4
       '@types/node':
         specifier: 'catalog:'
         version: 25.3.0
       '@types/send':
         specifier: 'catalog:'
         version: 1.2.1
+      mdast-util-mdx-jsx:
+        specifier: 'catalog:'
+        version: 3.2.0
       mdast-util-to-hast:
         specifier: 'catalog:'
         version: 13.2.1
+      remark-gfm:
+        specifier: 'catalog:'
+        version: 4.0.1
       typescript:
         specifier: 6.0.2
         version: 6.0.2

pnpm-workspace.yaml

@@ -60,6 +60,7 @@ catalog:
   '@lingui/swc-plugin': 5.11.0
   '@livekit/components-react': 2.9.20
   '@marsidev/react-turnstile': 1.4.2
+  '@mdx-js/mdx': 3.1.1
   '@messageformat/core': 3.4.0
   '@messageformat/parser': 5.1.1
   '@phosphor-icons/react': 2.1.10
@@ -79,6 +80,7 @@ catalog:
   '@types/hast': 3.0.5
   '@types/lodash': 4.17.24
   '@types/luxon': 3.7.1
+  '@types/mdast': 4.0.4
   '@types/node': 25.3.0
   '@types/nodemailer': 7.0.11
   '@types/pg': 8.16.0
@@ -127,6 +129,7 @@ catalog:
   luxon: 3.7.2
   match-sorter: 8.2.0
   maxmind: 5.0.5
+  mdast-util-mdx-jsx: 3.2.0
   mdast-util-to-hast: 13.2.1
   mime: 4.1.0
   mobx: 6.15.0
@@ -155,6 +158,7 @@ catalog:
   react-dom: 19.2.4
   react-hook-form: 7.71.2
   react-hotkeys-hook: 5.2.4
+  remark-gfm: 4.0.1
   rxjs: 7.8.2
   send: 1.2.1
   sharp: 0.35.4
@@ -171,6 +175,7 @@ catalog:
   typescript-eslint: 8.70.0
   uint8array-extras: 1.5.0
   undici: 7.29.0
+  undici-types: 7.18.2
   unique-names-generator: 4.7.1
   urlpattern-polyfill: 10.1.0
   valibot: 1.4.2

scripts/remote.mjs

@@ -1,370 +0,0 @@
-#!/usr/bin/env node
-// SPDX-License-Identifier: AGPL-3.0-or-later
-
-import {spawnSync} from 'node:child_process';
-import {existsSync, mkdirSync, readFileSync} from 'node:fs';
-import {homedir} from 'node:os';
-import path from 'node:path';
-import process from 'node:process';
-
-const repoRoot = path.resolve(new URL('..', import.meta.url).pathname);
-const defaultConfigPath = path.join(repoRoot, '.fluxer', 'remote-hosts.json');
-const defaultControlDir = path.join(repoRoot, '.fluxer', 'remote-ssh');
-
-function usage(exitCode = 0) {
-	console.log(`Usage:
-  pnpm remote list
-  pnpm remote doctor <host>
-  pnpm remote bootstrap <host> [--branch <branch>]
-  pnpm remote pull <host> [--branch <branch>]
-  pnpm remote run <host> -- <command>
-  pnpm remote apply-diff <host> [-- <path>...]
-  pnpm remote tunnel start|status|stop <host>
-  pnpm remote macos-setup [--pubkey ~/.ssh/id_ed25519.pub]
-
-Global options:
-  --config <path>   Host config path. Defaults to .fluxer/remote-hosts.json.
-  --verbose         Print spawned ssh commands.
-`);
-	process.exit(exitCode);
-}
-
-function fail(message, exitCode = 1) {
-	console.error(message);
-	process.exit(exitCode);
-}
-
-function parseGlobalArgs(argv) {
-	const options = {configPath: defaultConfigPath, verbose: false};
-	const rest = [];
-	for (let i = 0; i < argv.length; i++) {
-		const arg = argv[i];
-		if (arg === '--config') {
-			options.configPath = path.resolve(argv[++i] ?? fail('--config needs a path'));
-		} else if (arg === '--verbose') {
-			options.verbose = true;
-		} else if (arg === '--help' || arg === '-h') {
-			usage(0);
-		} else {
-			rest.push(arg);
-		}
-	}
-	return {options, args: rest};
-}
-
-function readJson(filePath) {
-	try {
-		return JSON.parse(readFileSync(filePath, 'utf8'));
-	} catch (error) {
-		fail(`Failed to read ${filePath}: ${error instanceof Error ? error.message : String(error)}`);
-	}
-}
-
-function loadConfig(configPath) {
-	if (!existsSync(configPath)) {
-		fail(
-			`Remote host config not found: ${configPath}\n` +
-				`Copy scripts/remote/hosts.example.json to .fluxer/remote-hosts.json and edit it.`,
-		);
-	}
-	const config = readJson(configPath);
-	if (!config || typeof config !== 'object' || !config.hosts || typeof config.hosts !== 'object') {
-		fail(`Invalid remote host config: ${configPath}`);
-	}
-	return config;
-}
-
-function getHost(config, name) {
-	const host = config.hosts[name];
-	if (!host || typeof host !== 'object') {
-		const known = Object.keys(config.hosts).sort().join(', ') || '(none)';
-		fail(`Unknown remote host "${name}". Known hosts: ${known}`);
-	}
-	if (typeof host.host !== 'string' || host.host.length === 0) {
-		fail(`Host "${name}" is missing "host"`);
-	}
-	if (host.platform !== 'windows' && host.platform !== 'macos' && host.platform !== 'linux') {
-		fail(`Host "${name}" needs platform "windows", "macos", or "linux"`);
-	}
-	return host;
-}
-
-function expandHome(value) {
-	if (typeof value !== 'string') return value;
-	if (value === '~') return homedir();
-	if (value.startsWith('~/')) return path.join(homedir(), value.slice(2));
-	return value;
-}
-
-function targetFor(host) {
-	return host.user ? `${host.user}@${host.host}` : host.host;
-}
-
-function controlPathFor(name, host) {
-	if (host.controlPath) return path.resolve(expandHome(host.controlPath));
-	mkdirSync(defaultControlDir, {recursive: true, mode: 0o700});
-	return path.join(defaultControlDir, `${name.replace(/[^A-Za-z0-9_.-]/g, '_')}.ctl`);
-}
-
-function sshBaseArgs(name, host, {control = true} = {}) {
-	const args = [];
-	if (host.port) args.push('-p', String(host.port));
-	if (host.identityFile) args.push('-i', path.resolve(expandHome(host.identityFile)));
-	args.push('-o', 'ServerAliveInterval=30', '-o', 'ServerAliveCountMax=3', '-o', 'StrictHostKeyChecking=accept-new');
-	if (control) {
-		args.push('-S', controlPathFor(name, host), '-o', 'ControlMaster=auto', '-o', 'ControlPersist=30m');
-	}
-	return args;
-}
-
-function forwardArgs(host) {
-	const forwards = Array.isArray(host.forwards) ? host.forwards : [];
-	const args = [];
-	for (const forward of forwards) {
-		if (typeof forward === 'string') {
-			args.push('-L', forward);
-		} else if (forward && typeof forward === 'object' && forward.local && forward.remote) {
-			args.push('-L', `${forward.local}:${forward.remote}`);
-		} else {
-			fail(`Invalid forward entry for ${host.host}`);
-		}
-	}
-	return args;
-}
-
-function shQuote(value) {
-	return `'${String(value).replace(/'/g, `'\\''`)}'`;
-}
-
-function psQuote(value) {
-	return `'${String(value).replace(/'/g, "''")}'`;
-}
-
-function remoteCommand(host, command) {
-	const repo = host.repo;
-	if (host.platform === 'windows') {
-		const body = `${repo ? `Set-Location -LiteralPath ${psQuote(repo)}; ` : ''}${command}`;
-		return `powershell.exe -NoProfile -ExecutionPolicy Bypass -EncodedCommand ${Buffer.from(body, 'utf16le').toString('base64')}`;
-	}
-	const body = `${repo ? `cd ${shQuote(repo)} && ` : ''}${command}`;
-	return `bash -lc ${shQuote(body)}`;
-}
-
-function spawnChecked(command, args, {verbose = false, input} = {}) {
-	if (verbose) console.error(`$ ${command} ${args.join(' ')}`);
-	const result = spawnSync(command, args, {
-		cwd: repoRoot,
-		input,
-		stdio: input === undefined ? 'inherit' : ['pipe', 'inherit', 'inherit'],
-	});
-	if (result.error) fail(`${command} failed to start: ${result.error.message}`);
-	if (result.status !== 0) process.exit(result.status ?? 1);
-}
-
-function spawnCapture(command, args) {
-	const result = spawnSync(command, args, {cwd: repoRoot, encoding: 'utf8'});
-	if (result.error || result.status !== 0) return null;
-	return result.stdout.trim();
-}
-
-function spawnCaptureRaw(command, args) {
-	const result = spawnSync(command, args, {cwd: repoRoot, encoding: 'utf8'});
-	if (result.error || result.status !== 0) return null;
-	return result.stdout;
-}
-
-function ssh(name, host, command, options = {}) {
-	spawnChecked('ssh', [...sshBaseArgs(name, host), targetFor(host), remoteCommand(host, command)], options);
-}
-
-function sshWithInput(name, host, command, input, options = {}) {
-	spawnChecked('ssh', [...sshBaseArgs(name, host), targetFor(host), remoteCommand(host, command)], {
-		...options,
-		input,
-	});
-}
-
-function currentBranch() {
-	return spawnCapture('git', ['rev-parse', '--abbrev-ref', 'HEAD']) || 'main';
-}
-
-function originUrl() {
-	return spawnCapture('git', ['config', '--get', 'remote.origin.url']) || '';
-}
-
-function splitAfterDoubleDash(args) {
-	const index = args.indexOf('--');
-	if (index === -1) return {head: args, tail: []};
-	return {head: args.slice(0, index), tail: args.slice(index + 1)};
-}
-
-function optionValue(args, name, fallback) {
-	const index = args.indexOf(name);
-	if (index === -1) return fallback;
-	const value = args[index + 1];
-	if (!value) fail(`${name} needs a value`);
-	return value;
-}
-
-function cloneOrUpdateCommand(host, branch) {
-	const repo = host.repo;
-	const repoUrl = host.repoUrl || originUrl();
-	if (!repo) fail('bootstrap/pull requires host.repo in the config');
-	if (!repoUrl) fail('bootstrap requires host.repoUrl or a local git remote.origin.url');
-	if (host.platform === 'windows') {
-		return [
-			`$repo = ${psQuote(repo)}`,
-			`$repoUrl = ${psQuote(repoUrl)}`,
-			`$branch = ${psQuote(branch)}`,
-			`if (!(Test-Path -LiteralPath (Join-Path $repo '.git'))) {`,
-			`  New-Item -ItemType Directory -Force -Path (Split-Path -Parent $repo) | Out-Null`,
-			`  git clone $repoUrl $repo`,
-			`}`,
-			`Set-Location -LiteralPath $repo`,
-			`git fetch --all --prune`,
-			`git checkout $branch`,
-			`git pull --ff-only`,
-			`corepack enable`,
-			`pnpm install`,
-		].join('; ');
-	}
-	return [
-		`repo=${shQuote(repo)}`,
-		`repo_url=${shQuote(repoUrl)}`,
-		`branch=${shQuote(branch)}`,
-		`if [ ! -d "$repo/.git" ]; then mkdir -p "$(dirname "$repo")"; git clone "$repo_url" "$repo"; fi`,
-		`cd "$repo"`,
-		`git fetch --all --prune`,
-		`git checkout "$branch"`,
-		`git pull --ff-only`,
-		`corepack enable`,
-		`pnpm install`,
-	].join(' && ');
-}
-
-function pullCommand(host, branch) {
-	const repo = host.repo;
-	if (!repo) fail('pull requires host.repo in the config');
-	if (host.platform === 'windows') {
-		return [
-			`Set-Location -LiteralPath ${psQuote(repo)}`,
-			`git fetch --all --prune`,
-			`git checkout ${psQuote(branch)}`,
-			`git pull --ff-only`,
-		].join('; ');
-	}
-	return [
-		`cd ${shQuote(repo)}`,
-		`git fetch --all --prune`,
-		`git checkout ${shQuote(branch)}`,
-		`git pull --ff-only`,
-	].join(' && ');
-}
-
-function macosSetup(args) {
-	const pubkeyPath = path.resolve(expandHome(optionValue(args, '--pubkey', '~/.ssh/id_ed25519.pub')));
-	const pubkey = existsSync(pubkeyPath) ? readFileSync(pubkeyPath, 'utf8').trim() : '<paste-your-public-ssh-key-here>';
-	console.log(`# Run this on the macOS machine while Tailscale is connected.
-sudo systemsetup -setremotelogin on
-mkdir -p ~/.ssh
-chmod 700 ~/.ssh
-printf '%s\\n' ${shQuote(pubkey)} >> ~/.ssh/authorized_keys
-chmod 600 ~/.ssh/authorized_keys
-tailscale status
-tailscale ip -4
-sudo lsof -nP -iTCP:22 -sTCP:LISTEN
-
-# Optional, only if you intentionally use Tailscale SSH ACLs instead of OpenSSH keys:
-# sudo tailscale up --ssh
-`);
-}
-
-const {options, args} = parseGlobalArgs(process.argv.slice(2));
-const command = args[0];
-if (!command) usage(1);
-
-if (command === 'macos-setup') {
-	macosSetup(args.slice(1));
-	process.exit(0);
-}
-
-const config = loadConfig(options.configPath);
-
-switch (command) {
-	case 'list': {
-		for (const [name, host] of Object.entries(config.hosts)) {
-			console.log(`${name}\t${host.platform}\t${targetFor(host)}\t${host.repo ?? ''}`);
-		}
-		break;
-	}
-	case 'doctor': {
-		const name = args[1] ?? fail('doctor needs a host');
-		const host = getHost(config, name);
-		const remote =
-			host.platform === 'windows'
-				? '$PSVersionTable.PSVersion.ToString(); git --version; node --version; pnpm --version; rustc --version; cargo --version; Get-ComputerInfo | Select-Object -ExpandProperty OsName'
-				: 'uname -a; git --version; node --version; pnpm --version; rustc --version; cargo --version';
-		ssh(name, host, remote, options);
-		break;
-	}
-	case 'bootstrap': {
-		const name = args[1] ?? fail('bootstrap needs a host');
-		const host = getHost(config, name);
-		ssh(name, host, cloneOrUpdateCommand(host, optionValue(args, '--branch', currentBranch())), options);
-		break;
-	}
-	case 'pull': {
-		const name = args[1] ?? fail('pull needs a host');
-		const host = getHost(config, name);
-		ssh(name, host, pullCommand(host, optionValue(args, '--branch', currentBranch())), options);
-		break;
-	}
-	case 'run': {
-		const {head, tail} = splitAfterDoubleDash(args.slice(1));
-		const name = head[0] ?? fail('run needs a host');
-		if (tail.length === 0) fail('run needs -- <command>');
-		ssh(name, getHost(config, name), tail.join(' '), options);
-		break;
-	}
-	case 'apply-diff': {
-		const {head, tail} = splitAfterDoubleDash(args.slice(1));
-		const name = head[0] ?? fail('apply-diff needs a host');
-		const host = getHost(config, name);
-		const diff = spawnCaptureRaw('git', ['diff', '--binary', '--', ...tail]);
-		if (!diff) {
-			console.log('No local diff to apply.');
-			break;
-		}
-		sshWithInput(name, host, 'git apply --whitespace=nowarn -', diff, options);
-		break;
-	}
-	case 'tunnel': {
-		const action = args[1] ?? fail('tunnel needs start|status|stop');
-		const name = args[2] ?? fail('tunnel needs a host');
-		const host = getHost(config, name);
-		if (action === 'start') {
-			spawnChecked(
-				'ssh',
-				[
-					...sshBaseArgs(name, host),
-					...forwardArgs(host),
-					'-fN',
-					'-M',
-					'-o',
-					'ExitOnForwardFailure=yes',
-					targetFor(host),
-				],
-				options,
-			);
-		} else if (action === 'status') {
-			spawnChecked('ssh', [...sshBaseArgs(name, host), '-O', 'check', targetFor(host)], options);
-		} else if (action === 'stop') {
-			spawnChecked('ssh', [...sshBaseArgs(name, host), '-O', 'exit', targetFor(host)], options);
-		} else {
-			fail('tunnel action must be start, status, or stop');
-		}
-		break;
-	}
-	default:
-		usage(1);
-}

scripts/remote/hosts.example.json

@@ -1,22 +0,0 @@
-{
-	"hosts": {
-		"windows-iva": {
-			"platform": "windows",
-			"host": "iva",
-			"user": "Hampus",
-			"repo": "C:\\Users\\Hampus\\src\\fluxer-private",
-			"repoUrl": "[email protected]:REPLACE_ME/fluxer-private.git",
-			"identityFile": "~/.ssh/id_ed25519",
-			"forwards": []
-		},
-		"macos": {
-			"platform": "macos",
-			"host": "replace-with-mac-tailnet-name",
-			"user": "replace-with-mac-username",
-			"repo": "/Users/replace-with-mac-username/src/fluxer-private",
-			"repoUrl": "[email protected]:REPLACE_ME/fluxer-private.git",
-			"identityFile": "~/.ssh/id_ed25519",
-			"forwards": []
-		}
-	}
-}

tools/ci/src/app_proxy.rs

@@ -6,6 +6,7 @@ use crate::common::{
     remove_dir_if_exists, require_env, resolve_calver, run_command, runner_temp, s3_client,
     trim_option, upload_s3_plan_append_only,
 };
+use crate::functions::sha256_reader;
 use anyhow::{Context, Result, anyhow, ensure};
 use base64::Engine;
 use base64::engine::general_purpose::STANDARD as BASE64;
@@ -13,11 +14,9 @@ use chrono::Utc;
 use clap::{Args, ValueEnum};
 use reqwest::Client;
 use serde_json::{Map, Value, json};
-use sha2::{Digest, Sha256};
 use std::collections::{BTreeMap, BTreeSet};
 use std::env;
 use std::fs::{self, File};
-use std::io::Read;
 use std::path::{Path, PathBuf};
 use std::sync::Arc;
 use std::time::Duration;
@@ -586,20 +585,8 @@ fn asset_tree_digests(root: &Path) -> Result<BTreeMap<String, String>> {
 }
 
 fn sha256_file(path: &Path) -> Result<String> {
-    let mut file =
+    let file = File::open(path).with_context(|| format!("Failed to open {}", path.display()))?;
-        File::open(path).with_context(|| format!("Failed to open {}", path.display()))?;
+    sha256_reader(file).with_context(|| format!("Failed to read {}", path.display()))
-    let mut hasher = Sha256::new();
-    let mut buffer = [0u8; 64 * 1024];
-    loop {
-        let read = file
-            .read(&mut buffer)
-            .with_context(|| format!("Failed to read {}", path.display()))?;
-        if read == 0 {
-            break;
-        }
-        hasher.update(&buffer[..read]);
-    }
-    Ok(hex::encode(hasher.finalize()))
 }
 
 fn tree_differences(

tools/ci/src/calver.rs

@@ -1,8 +1,8 @@
 // SPDX-License-Identifier: AGPL-3.0-or-later
 
 use crate::common::{
-    CALVER_SCHEME, CalverEnv, append_github_env, append_github_output, parse_version_instant,
+    CALVER_SCHEME, CalverEnv, append_github_env, append_github_output, micro_segment,
-    resolve_calver, trim_option,
+    month_day_segment, parse_version_instant, resolve_calver, trim_option,
 };
 use anyhow::Result;
 use chrono::{Datelike, Timelike, Utc};
@@ -75,14 +75,10 @@ fn calver_outputs(version: &str) -> Result<CalverOutputs> {
         instant.minute(),
         instant.second()
     );
-    let micro = time
-        .parse::<u32>()
-        .expect("HHMMSS time segment should parse")
-        .to_string();
     Ok(CalverOutputs {
         version: version.to_string(),
         time,
-        micro,
+        micro: micro_segment(instant),
         date: format!(
             "{:04}{:02}{:02}",
             instant.year(),
@@ -92,7 +88,7 @@ fn calver_outputs(version: &str) -> Result<CalverOutputs> {
         year: instant.year().to_string(),
         month: instant.month().to_string(),
         day: format!("{:02}", instant.day()),
-        month_day: format!("{}{:02}", instant.month(), instant.day()),
+        month_day: month_day_segment(instant),
     })
 }
 

tools/ci/src/common.rs

@@ -365,20 +365,12 @@ fn format_calver(instant: DateTime<Utc>) -> String {
     )
 }
 
-fn month_day_segment(instant: DateTime<Utc>) -> String {
+pub(crate) fn month_day_segment(instant: DateTime<Utc>) -> String {
     format!("{}{:02}", instant.month(), instant.day())
 }
 
-fn micro_segment(instant: DateTime<Utc>) -> String {
+pub(crate) fn micro_segment(instant: DateTime<Utc>) -> String {
-    format!(
+    (instant.hour() * 10_000 + instant.minute() * 100 + instant.second()).to_string()
-        "{:02}{:02}{:02}",
-        instant.hour(),
-        instant.minute(),
-        instant.second()
-    )
-    .parse::<u32>()
-    .expect("HHMMSS time segment should parse")
-    .to_string()
 }
 
 pub(crate) fn parse_version_instant(version: &str) -> Result<DateTime<Utc>> {
@@ -1312,13 +1304,13 @@ pub(crate) fn collect_files(root: &Path) -> Result<Vec<PathBuf>> {
     if !root.exists() {
         return Ok(Vec::new());
     }
-    let mut files = WalkDir::new(root)
+    let mut files = Vec::new();
-        .into_iter()
+    for entry in WalkDir::new(root) {
-        .collect::<std::result::Result<Vec<_>, _>>()?
+        let entry = entry?;
-        .into_iter()
+        if entry.file_type().is_file() {
-        .filter(|entry| entry.file_type().is_file())
+            files.push(entry.into_path());
-        .map(|entry| entry.into_path())
+        }
-        .collect::<Vec<_>>();
+    }
     files.sort();
     Ok(files)
 }
@@ -1328,13 +1320,13 @@ pub(crate) fn count_files(root: &Path) -> Result<usize> {
 }
 
 pub(crate) fn count_files_min_depth(root: &Path, min_depth: usize) -> Result<usize> {
-    Ok(WalkDir::new(root)
+    let mut count = 0;
-        .min_depth(min_depth)
+    for entry in WalkDir::new(root).min_depth(min_depth) {
-        .into_iter()
+        if entry?.file_type().is_file() {
-        .collect::<std::result::Result<Vec<_>, _>>()?
+            count += 1;
-        .into_iter()
+        }
-        .filter(|entry| entry.file_type().is_file())
+    }
-        .count())
+    Ok(count)
 }
 
 pub(crate) fn title_case(value: &str) -> String {

tools/ci/src/functions.rs

@@ -2,8 +2,9 @@
 
 use anyhow::{Context, Result};
 use serde::Serialize;
+use sha2::{Digest, Sha256};
 use std::fs;
-use std::io;
+use std::io::{self, Read};
 use std::path::Path;
 
 pub(crate) fn remove_file_if_exists(path: &Path) -> Result<()> {
@@ -32,6 +33,19 @@ pub(crate) fn write_json_pretty<T: Serialize + ?Sized>(path: &Path, value: &T) -
     fs::write(path, bytes).with_context(|| format!("Failed to write {}", path.display()))
 }
 
+pub(crate) fn sha256_reader(mut reader: impl Read) -> io::Result<String> {
+    let mut hasher = Sha256::new();
+    let mut buffer = [0u8; 64 * 1024];
+    loop {
+        let read = reader.read(&mut buffer)?;
+        if read == 0 {
+            break;
+        }
+        hasher.update(&buffer[..read]);
+    }
+    Ok(hex::encode(hasher.finalize()))
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

tools/ci/src/release.rs

@@ -1,14 +1,13 @@
 // SPDX-License-Identifier: AGPL-3.0-or-later
 
 use crate::common::{CommandSpec, output_text, parse_version_instant, run_command};
+use crate::functions::sha256_reader;
 use anyhow::{Context, Result, bail, ensure};
 use chrono::{DateTime, Utc};
 use clap::{Args, Subcommand};
 use serde::{Deserialize, Serialize};
-use sha2::{Digest, Sha256};
 use std::collections::{BTreeMap, BTreeSet};
 use std::fs::{self, File};
-use std::io::Read;
 use std::path::{Path, PathBuf};
 use std::thread;
 use std::time::Duration;
@@ -753,20 +752,9 @@ fn local_release_assets(
 }
 
 fn sha256_file(path: &Path) -> Result<String> {
-    let mut file = File::open(path)
+    let file = File::open(path)
         .with_context(|| format!("Failed to open release asset {}", path.display()))?;
-    let mut hasher = Sha256::new();
+    sha256_reader(file).with_context(|| format!("Failed to read release asset {}", path.display()))
-    let mut buffer = [0u8; 64 * 1024];
-    loop {
-        let read = file
-            .read(&mut buffer)
-            .with_context(|| format!("Failed to read release asset {}", path.display()))?;
-        if read == 0 {
-            break;
-        }
-        hasher.update(&buffer[..read]);
-    }
-    Ok(hex::encode(hasher.finalize()))
 }
 
 fn create_draft_release(

tools/ci/src/schema.rs

@@ -46,9 +46,6 @@ fn find_import_start(source: &str) -> Option<usize> {
         }
         offset += line.len();
     }
-    if source[offset..].starts_with("import ") {
-        return Some(offset);
-    }
     None
 }
 

tools/dev/Cargo.toml

@@ -22,8 +22,6 @@ scylla = { version = "1.6.0", features = ["chrono-04"] }
 serde = { version = "1.0.228", features = ["derive"] }
 serde_json = "1.0.150"
 sha2 = "0.11.0"
+tempfile = "3.27.0"
 tokio = { version = "1.52.3", features = ["fs", "io-util", "macros", "net", "process", "rt-multi-thread", "signal", "time"] }
 url = "2.5.8"
-
-[dev-dependencies]
-tempfile = "3.27.0"

tools/dev/cassandra_target_schema.json

@@ -788,6 +788,10 @@
 					"name": "requested_at",
 					"type": "timestamp"
 				},
+				{
+					"name": "attempt_id",
+					"type": "text"
+				},
 				{
 					"name": "started_at",
 					"type": "timestamp"
@@ -800,6 +804,10 @@
 					"name": "failed_at",
 					"type": "timestamp"
 				},
+				{
+					"name": "terminal_failed_at",
+					"type": "timestamp"
+				},
 				{
 					"name": "storage_key",
 					"type": "text"
@@ -7893,6 +7901,10 @@
 					"name": "verification_token",
 					"type": "text"
 				},
+				{
+					"name": "oauth_grant_id",
+					"type": "text"
+				},
 				{
 					"name": "verified_at",
 					"type": "timestamp"
@@ -7905,9 +7917,25 @@
 					"name": "created_at",
 					"type": "timestamp"
 				},
+				{
+					"name": "revision",
+					"type": "text"
+				},
 				{
 					"name": "version",
 					"type": "int"
+				},
+				{
+					"name": "membership",
+					"type": "text"
+				},
+				{
+					"name": "credential_payload",
+					"type": "text"
+				},
+				{
+					"name": "credential_expires_at",
+					"type": "timestamp"
 				}
 			],
 			"primary_key": "((user_id), connection_type, connection_id)",
@@ -8172,6 +8200,10 @@
 					"name": "requested_at",
 					"type": "timestamp"
 				},
+				{
+					"name": "attempt_id",
+					"type": "text"
+				},
 				{
 					"name": "started_at",
 					"type": "timestamp"
@@ -8184,6 +8216,10 @@
 					"name": "failed_at",
 					"type": "timestamp"
 				},
+				{
+					"name": "terminal_failed_at",
+					"type": "timestamp"
+				},
 				{
 					"name": "storage_key",
 					"type": "text"
@@ -8562,6 +8598,10 @@
 					"name": "pending_deletion_at",
 					"type": "timestamp"
 				},
+				{
+					"name": "deletion_started_at",
+					"type": "timestamp"
+				},
 				{
 					"name": "pending_bulk_message_deletion_at",
 					"type": "timestamp"

tools/dev/src/paths.rs

@@ -79,19 +79,7 @@ pub fn which(name: &str) -> Option<PathBuf> {
 }
 
 fn is_writable(path: &Path) -> bool {
-    let probe = path.join(".fluxer-write-test");
+    tempfile::NamedTempFile::new_in(path).is_ok()
-    match std::fs::OpenOptions::new()
-        .create(true)
-        .write(true)
-        .truncate(true)
-        .open(&probe)
-    {
-        Ok(_) => {
-            let _ = std::fs::remove_file(probe);
-            true
-        }
-        Err(_) => false,
-    }
 }
 
 #[cfg(unix)]

tools/dev/src/proc.rs

@@ -130,7 +130,7 @@ pub fn run_command(args: &[&str], options: RunOptions<'_>) -> Result<Output> {
         .current_dir(options.cwd)
         .env_clear()
         .envs(env);
-    if options.capture {
+    let output = if options.capture {
         command.stdout(Stdio::piped()).stderr(Stdio::piped());
         let output = command
             .output()
@@ -142,27 +142,20 @@ pub fn run_command(args: &[&str], options: RunOptions<'_>) -> Result<Output> {
         if !text.trim_end().is_empty() {
             println!("{}", text.trim_end());
         }
-        if options.check && !output.status.success() {
+        output
-            let code = output.status.code().unwrap_or(-1);
+    } else {
-            bail!(
+        command
-                "Command failed with exit code {code}: {}",
+            .stdin(Stdio::inherit())
-                format_command(args)
+            .stdout(Stdio::inherit())
-            );
+            .stderr(Stdio::inherit());
+        let status = command
+            .status()
+            .with_context(|| format!("failed to run {}", format_command(args)))?;
+        Output {
+            status,
+            stdout: Vec::new(),
+            stderr: Vec::new(),
         }
-        return Ok(output);
-    }
-
-    command
-        .stdin(Stdio::inherit())
-        .stdout(Stdio::inherit())
-        .stderr(Stdio::inherit());
-    let status = command
-        .status()
-        .with_context(|| format!("failed to run {}", format_command(args)))?;
-    let output = Output {
-        status,
-        stdout: Vec::new(),
-        stderr: Vec::new(),
     };
     if options.check && !output.status.success() {
         let code = output.status.code().unwrap_or(-1);