feat(app): gate the expression info card behind an experiment (#2773)

fluxer_api/src/api/instance/InstanceConfigRepository.test.ts

@@ -21,6 +21,10 @@ import {
 	DEFAULT_EXPERIMENT_DELIVERY_CONFIG,
 	type ExperimentDeliveryConfig,
 } from '@fluxer/schema/src/domains/experiment/ExperimentSchemas';
+import {
+	DEFAULT_EXPRESSION_INFO_CARD_CONFIG,
+	type ExpressionInfoCardConfig,
+} from '@fluxer/schema/src/domains/experiment/ExpressionInfoCardSchemas';
 import {
 	DEFAULT_GUILD_ACTIVITY_LOG_PRESENTATION_CONFIG,
 	type GuildActivityLogPresentationConfig,
@@ -40,6 +44,7 @@ const MESSAGE_HOVER_TRACKING_CONFIG_KEY = 'message_hover_tracking_config';
 const MESSAGE_KEYBOARD_FOCUS_CONFIG_KEY = 'message_keyboard_focus_config';
 const BLOCKED_MESSAGE_GROUPS_CONFIG_KEY = 'blocked_message_groups_config';
 const GUILD_ACTIVITY_LOG_PRESENTATION_CONFIG_KEY = 'guild_activity_log_presentation_config';
+const EXPRESSION_INFO_CARD_CONFIG_KEY = 'expression_info_card_config';
 const EXPERIMENT_DELIVERY_CONFIG_KEY = 'experiment_delivery_config';
 const APP_PUBLIC_CONFIG_KEY = 'app_public_config';
 const INSTANCE_POLICY_CONFIG_KEY = 'instance_policy_config';
@@ -516,6 +521,51 @@ describe('InstanceConfigRepository', () => {
 		await expect(repository.getGuildActivityLogPresentationConfig()).resolves.toEqual(config);
 	});
 
+	it('returns the default expression info card config when the key is absent', async () => {
+		const executor = new CountingInMemoryCassandraQueryExecutor();
+		setCassandraQueryExecutorForTesting(executor);
+		const kvProvider = new MockKVProvider();
+		const repository = createRepository(kvProvider);
+
+		await expect(repository.getExpressionInfoCardConfig()).resolves.toEqual(DEFAULT_EXPRESSION_INFO_CARD_CONFIG);
+	});
+
+	it.each([
+		{name: 'unparseable text', stored: 'not-json'},
+		{name: 'a json array', stored: '[]'},
+		{name: 'out-of-range values', stored: '{"rollout_basis_points":99999}'},
+		{name: 'a target that is not a snowflake', stored: '{"included_user_ids":["nope"]}'},
+	])('falls back to the default expression info card config for $name', async ({stored}) => {
+		const executor = new CountingInMemoryCassandraQueryExecutor();
+		setCassandraQueryExecutorForTesting(executor);
+		const kvProvider = new MockKVProvider();
+		const repository = createRepository(kvProvider);
+
+		await repository.setConfig(EXPRESSION_INFO_CARD_CONFIG_KEY, stored);
+
+		await expect(repository.getExpressionInfoCardConfig()).resolves.toEqual(DEFAULT_EXPRESSION_INFO_CARD_CONFIG);
+	});
+
+	it('round-trips a stored expression info card config', async () => {
+		const executor = new CountingInMemoryCassandraQueryExecutor();
+		setCassandraQueryExecutorForTesting(executor);
+		const kvProvider = new MockKVProvider();
+		const repository = createRepository(kvProvider);
+
+		const config: ExpressionInfoCardConfig = {
+			...DEFAULT_EXPRESSION_INFO_CARD_CONFIG,
+			enabled: true,
+			config_version: 5,
+			rollout_basis_points: 2500,
+			rollout_salt: 'expression-info-card-v2',
+			included_user_ids: ['1400000000000000001'],
+			excluded_user_ids: ['1400000000000000002'],
+		};
+		await repository.setExpressionInfoCardConfig(config);
+
+		await expect(repository.getExpressionInfoCardConfig()).resolves.toEqual(config);
+	});
+
 	it('fills newly added voice noise suppression fields from the schema defaults', async () => {
 		const executor = new CountingInMemoryCassandraQueryExecutor();
 		setCassandraQueryExecutorForTesting(executor);

fluxer_api/src/api/instance/InstanceConfigRepository.ts

@@ -40,6 +40,10 @@ import {
 	type ExperimentDeliveryConfig,
 	ExperimentDeliveryConfigSchema,
 } from '@fluxer/schema/src/domains/experiment/ExperimentSchemas';
+import {
+	type ExpressionInfoCardConfig,
+	ExpressionInfoCardConfigSchema,
+} from '@fluxer/schema/src/domains/experiment/ExpressionInfoCardSchemas';
 import {
 	type GuildActivityLogPresentationConfig,
 	GuildActivityLogPresentationConfigSchema,
@@ -75,6 +79,7 @@ const EXPERIMENT_DELIVERY_CONFIG_KEY = 'experiment_delivery_config';
 const MESSAGE_HOVER_TRACKING_CONFIG_KEY = 'message_hover_tracking_config';
 const MESSAGE_KEYBOARD_FOCUS_CONFIG_KEY = 'message_keyboard_focus_config';
 const BLOCKED_MESSAGE_GROUPS_CONFIG_KEY = 'blocked_message_groups_config';
+const EXPRESSION_INFO_CARD_CONFIG_KEY = 'expression_info_card_config';
 const REGISTRATION_CONFIG_KEY = 'registration_config';
 const REGISTRATION_URLS_KEY = 'registration_urls';
 const REGISTRATION_PENDING_APPROVALS_KEY = 'registration_pending_approvals';
@@ -362,6 +367,7 @@ type StoredConfigSection =
 	| 'message hover tracking'
 	| 'message keyboard focus'
 	| 'blocked message groups'
+	| 'expression info card'
 	| 'instance policy'
 	| 'integrations'
 	| 'media'
@@ -519,6 +525,10 @@ function parseStoredBlockedMessageGroupsConfig(raw: string | null): BlockedMessa
 	return parseStoredConfigOrDefault(BlockedMessageGroupsConfigSchema, raw, 'blocked message groups');
 }
 
+function parseStoredExpressionInfoCardConfig(raw: string | null): ExpressionInfoCardConfig {
+	return parseStoredConfigOrDefault(ExpressionInfoCardConfigSchema, raw, 'expression info card');
+}
+
 function validateStoredCollection<T>(schema: z.ZodType<T>, value: unknown, section: StoredConfigSection): Array<T> {
 	if (!Array.isArray(value)) {
 		throw new Error(`Stored ${section} configuration must be an array`);
@@ -1042,6 +1052,7 @@ export class InstanceConfigRepository {
 		parseStoredMessageHoverTrackingConfig(snapshot.get(MESSAGE_HOVER_TRACKING_CONFIG_KEY) ?? null);
 		parseStoredMessageKeyboardFocusConfig(snapshot.get(MESSAGE_KEYBOARD_FOCUS_CONFIG_KEY) ?? null);
 		parseStoredBlockedMessageGroupsConfig(snapshot.get(BLOCKED_MESSAGE_GROUPS_CONFIG_KEY) ?? null);
+		parseStoredExpressionInfoCardConfig(snapshot.get(EXPRESSION_INFO_CARD_CONFIG_KEY) ?? null);
 		const policy = parseStoredInstancePolicyConfig(snapshot.get(INSTANCE_POLICY_CONFIG_KEY) ?? null);
 		checkStoredConfig('registration', () =>
 			parseStoredRegistrationConfig(snapshot.get(REGISTRATION_CONFIG_KEY) ?? null),
@@ -1171,6 +1182,16 @@ export class InstanceConfigRepository {
 		await this.setConfig(BLOCKED_MESSAGE_GROUPS_CONFIG_KEY, JSON.stringify(validated));
 	}
 
+	async getExpressionInfoCardConfig(): Promise<ExpressionInfoCardConfig> {
+		const raw = await this.getConfig(EXPRESSION_INFO_CARD_CONFIG_KEY);
+		return parseStoredExpressionInfoCardConfig(raw);
+	}
+
+	async setExpressionInfoCardConfig(config: ExpressionInfoCardConfig): Promise<void> {
+		const validated = validateStoredConfig(ExpressionInfoCardConfigSchema, config, 'expression info card');
+		await this.setConfig(EXPRESSION_INFO_CARD_CONFIG_KEY, JSON.stringify(validated));
+	}
+
 	async setExperimentDeliveryConfig(config: ExperimentDeliveryConfig): Promise<void> {
 		const validated = validateStoredConfig(ExperimentDeliveryConfigSchema, config, 'experiment delivery');
 		await this.setConfig(EXPERIMENT_DELIVERY_CONFIG_KEY, JSON.stringify(validated));