fix(api): skip the mature gate when no birth date is collected (#2582)

fluxer_api/src/api/instance/DateOfBirthCollectionCache.ts

@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+import {Config} from '../Config';
+
+let cachedCollectDateOfBirth: boolean | null = null;
+
+export function getDefaultDateOfBirthCollection(): boolean {
+	return !Config.instance.selfHosted;
+}
+
+export function instanceCollectsDateOfBirth(): boolean {
+	return cachedCollectDateOfBirth ?? getDefaultDateOfBirthCollection();
+}
+
+export function setCachedDateOfBirthCollection(collect: boolean): void {
+	cachedCollectDateOfBirth = collect;
+}

fluxer_api/src/api/instance/InstanceConfigRepository.ts

@@ -17,6 +17,7 @@ import {resolveDeferredPhoneGateEnabled, setCachedDeferredPhoneGateEnabled} from
 import {InstanceConfiguration} from '../Tables';
 import {DEFAULT_DECAY_CONSTANTS, DEFAULT_RENEWAL_CONSTANTS} from '../utils/AttachmentDecay';
 import {isJsonRecord, parseJsonArray, parseJsonRecord} from '../utils/JsonBoundaryUtils';
+import {getDefaultDateOfBirthCollection, setCachedDateOfBirthCollection} from './DateOfBirthCollectionCache';
 import {normalizeSsoAllowedEmailDomains} from './SsoConfigValidation';
 
 const GATEWAY_ROLLOUT_CONFIG_KEY = 'gateway_rollout_config';
@@ -357,11 +358,21 @@ function getDefaultAppPublicConfig(): InstanceAppPublicConfig {
 			privacy_url: null,
 		},
 		registration: {
-			collect_date_of_birth: !Config.instance.selfHosted,
+			collect_date_of_birth: getDefaultDateOfBirthCollection(),
 		},
 	};
 }
 
+function parseAppPublicConfig(raw: string): InstanceAppPublicConfig {
+	try {
+		const parsed: unknown = JSON.parse(raw);
+		return normalizeAppPublicConfig(parsed);
+	} catch (error) {
+		Logger.warn({error}, 'Invalid app public config JSON, returning defaults');
+		return getDefaultAppPublicConfig();
+	}
+}
+
 function normalizeAppPublicConfig(value: unknown): InstanceAppPublicConfig {
 	const defaults = getDefaultAppPublicConfig();
 	if (!isJsonRecord(value)) {
@@ -939,6 +950,7 @@ export class InstanceConfigRepository {
 				this.configCache = await this.fetchAllConfigsFromDatabase();
 			} while (this.refreshRequested);
 			this.syncDeferredPhoneGateCache(this.configCache.get(INSTANCE_POLICY_CONFIG_KEY) ?? null);
+			this.syncDateOfBirthCollectionCache(this.configCache.get(APP_PUBLIC_CONFIG_KEY) ?? null);
 		})().finally(() => {
 			this.refreshPromise = null;
 		});
@@ -950,6 +962,11 @@ export class InstanceConfigRepository {
 		setCachedDeferredPhoneGateEnabled(resolveDeferredPhoneGateEnabled(policy));
 	}
 
+	private syncDateOfBirthCollectionCache(raw: string | null): void {
+		const appPublic = raw ? normalizeAppPublicConfig(parseJsonRecord(raw)) : getDefaultAppPublicConfig();
+		setCachedDateOfBirthCollection(appPublic.registration.collect_date_of_birth);
+	}
+
 	private updateCachedConfigs(entries: Array<[string, string]>): void {
 		if (!this.configCache) {
 			return;
@@ -1067,16 +1084,9 @@ export class InstanceConfigRepository {
 
 	async getAppPublicConfig(): Promise<InstanceAppPublicConfig> {
 		const raw = await this.getConfig(APP_PUBLIC_CONFIG_KEY);
-		if (!raw) {
-			return getDefaultAppPublicConfig();
-		}
-		try {
-			const parsed: unknown = JSON.parse(raw);
-			return normalizeAppPublicConfig(parsed);
-		} catch (error) {
-			Logger.warn({error}, 'Invalid app public config JSON, returning defaults');
-			return getDefaultAppPublicConfig();
-		}
+		const config = raw ? parseAppPublicConfig(raw) : getDefaultAppPublicConfig();
+		setCachedDateOfBirthCollection(config.registration.collect_date_of_birth);
+		return config;
 	}
 
 	async setAppPublicConfig(config: {
@@ -1105,6 +1115,7 @@ export class InstanceConfigRepository {
 			},
 		});
 		await this.setConfig(APP_PUBLIC_CONFIG_KEY, JSON.stringify(next));
+		setCachedDateOfBirthCollection(next.registration.collect_date_of_birth);
 		return next;
 	}
 

fluxer_api/src/api/utils/AgeUtils.test.ts

@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+import {afterEach, describe, expect, it} from 'vitest';
+import {setCachedDateOfBirthCollection} from '../instance/DateOfBirthCollectionCache';
+import {canUserAccessNsfwContent} from './AgeUtils';
+
+const ADULT_DATE_OF_BIRTH = '1990-01-01';
+const MINOR_DATE_OF_BIRTH = '2020-01-01';
+
+describe('canUserAccessNsfwContent', () => {
+	afterEach(() => {
+		setCachedDateOfBirthCollection(true);
+	});
+
+	it('allows a bot whatever the instance collects', () => {
+		setCachedDateOfBirthCollection(true);
+		expect(canUserAccessNsfwContent({isBot: true, dateOfBirth: null})).toBe(true);
+	});
+
+	it('allows an adult when the instance collects a date of birth', () => {
+		setCachedDateOfBirthCollection(true);
+		expect(canUserAccessNsfwContent({isBot: false, dateOfBirth: ADULT_DATE_OF_BIRTH})).toBe(true);
+	});
+
+	it('blocks a minor when the instance collects a date of birth', () => {
+		setCachedDateOfBirthCollection(true);
+		expect(canUserAccessNsfwContent({isBot: false, dateOfBirth: MINOR_DATE_OF_BIRTH})).toBe(false);
+	});
+
+	it('blocks a missing date of birth when the instance collects one', () => {
+		setCachedDateOfBirthCollection(true);
+		expect(canUserAccessNsfwContent({isBot: false, dateOfBirth: null})).toBe(false);
+	});
+
+	it('allows a missing date of birth when the instance collects none', () => {
+		setCachedDateOfBirthCollection(false);
+		expect(canUserAccessNsfwContent({isBot: false, dateOfBirth: null})).toBe(true);
+	});
+
+	it('allows an account with a minor date of birth when the instance collects none', () => {
+		setCachedDateOfBirthCollection(false);
+		expect(canUserAccessNsfwContent({isBot: false, dateOfBirth: MINOR_DATE_OF_BIRTH})).toBe(true);
+	});
+});

fluxer_api/src/api/utils/AgeUtils.ts

@@ -1,5 +1,7 @@
 // SPDX-License-Identifier: AGPL-3.0-or-later
 
+import {instanceCollectsDateOfBirth} from '../instance/DateOfBirthCollectionCache';
+
 export function calculateAge(
 	dateOfBirth:
 		| {
@@ -53,5 +55,8 @@ export function canUserAccessNsfwContent(user: NsfwEligibilityUser): boolean {
 	if (user.isBot) {
 		return true;
 	}
+	if (!instanceCollectsDateOfBirth()) {
+		return true;
+	}
 	return isUserAdult(user.dateOfBirth);
 }