fix: resolve all issues assigned to Mercy60 (#364, #365, #375, #376)

BackendAcademy/src/app.module.ts

@@ -18,6 +18,15 @@ import { SubmissionModule } from './submissions/submission.module';
 import { RewardsModule } from './rewards/rewards.module';
 import { SecurityModule } from './security/security.module';
 import { AppConfigModule } from './config/config.module';
+import { AssetsModule } from './assets/assets.module';
+import { PathfindingModule } from './pathfinding/pathfinding.module';
+import { MonitoringModule } from './monitoring/monitoring.module';
+import { SearchModule } from './search/search.module';
+import { PaymentsModule } from './payments/payments.module';
+import { I18nModule } from './i18n/i18n.module';
+import { NotificationsModule } from './notifications/notifications.module';
+import { HealthModule } from './health/health.module';
+import { CorrelationIdMiddleware } from './common/correlation-id.middleware';
 
 /**
  * Root application module.
@@ -44,6 +53,27 @@ import { AppConfigModule } from './config/config.module';
     SubmissionModule,
     RewardsModule,
     SecurityModule,
+    ChallengesModule,
+    AiModule,
+    LeaderboardModule,
+    AnalyticsModule,
+    WalletModule,
+    SocialModule,
+    OnboardingModule,
+    LessonModule,
+    TaskModule,
+    CourseModule,
+    AssetsModule,
+    LoggingModule,
+    PathfindingModule,
+    MonitoringModule,
+    ProgressModule,
+    SearchModule,
+    PaymentsModule,
+    I18nModule,
+    NotificationsModule,
+    // #375, #376: Health + readiness probe module
+    HealthModule,
   ],
   controllers: [AppController],
   providers: [
@@ -59,4 +89,3 @@ export class AppModule implements NestModule {
     consumer.apply(CorrelationIdMiddleware).forRoutes('*');
   }
 }
-export class AppModule {}

BackendAcademy/src/config/config.module.ts

@@ -1,5 +1,7 @@
 import { Module } from '@nestjs/common';
 import { ConfigModule as NestConfigModule } from '@nestjs/config';
+import * as Joi from 'joi';
+import { contractEnvSchema } from './env.schema';
 import { envSchema } from './env.schema';
 
 /**
@@ -10,6 +12,76 @@ import { envSchema } from './env.schema';
   imports: [
     NestConfigModule.forRoot({
       isGlobal: true,
+      validationSchema: contractEnvSchema.concat(
+        Joi.object({
+        // ── Base config ─────────────────────────────────────────────
+        NODE_ENV: Joi.string().valid('development', 'production', 'test').default('development'),
+        PORT: Joi.number().default(3000),
+        CORS_ORIGIN: Joi.string().optional(),
+        DATABASE_URL: Joi.string().optional(),
+        REDIS_HOST: Joi.string().default('localhost'),
+        REDIS_PORT: Joi.number().default(6379),
+        JWT_SECRET: Joi.string().optional(),
+        AI_PROVIDER: Joi.string().valid('claude', 'openai', 'mock').default('mock'),
+        ANTHROPIC_API_KEY: Joi.string().optional(),
+        OPENAI_API_KEY: Joi.string().optional(),
+        AI_MODEL: Joi.string().optional(),
+        AI_MAX_TOKENS: Joi.number().default(4096),
+        AI_TEMPERATURE: Joi.number().default(0.7),
+        LOCALE: Joi.string().default('en'),
+
+        // ── Cron schedules ──────────────────────────────────────────
+        CRON_CLEANUP_SCHEDULE: Joi.string().default('0 0 * * *'),
+        CRON_ANALYTICS_SCHEDULE: Joi.string().default('0 */6 * * *'),
+        CRON_NOTIFICATIONS_SCHEDULE: Joi.string().default('*/30 * * * *'),
+        CRON_CONTRACT_REPLAY_SCHEDULE: Joi.string().optional(),
+
+        // ── #395: Feature flags for contract ingestion ───────────────
+        CONTRACT_INGESTION_ENABLED: Joi.string()
+          .valid('true', 'false')
+          .default('false')
+          .description('Must be explicitly "true" to enable contract ingestion.'),
+
+        // ── #393: Contract registry schema validation ────────────────
+        CONTRACT_REGISTRY_REQUIRE_SCHEMA: Joi.string()
+          .valid('true', 'false')
+          .default('true')
+          .description('When "true", registry entries must pass schema compatibility checks.'),
+
+        // ── #394: Event replay ────────────────────────────────────────
+        CONTRACT_EVENT_REPLAY_ENABLED: Joi.string()
+          .valid('true', 'false')
+          .default('false')
+          .description('When "true", contract event replay is available.'),
+
+        // ── #396: Contract adapter config ────────────────────────────
+        CONTRACT_ADAPTER_MODE: Joi.string()
+          .valid('native', 'stellar', 'mock')
+          .default('mock'),
+        CONTRACT_NETWORK: Joi.string()
+          .valid('testnet', 'futurenet', 'mainnet')
+          .default('testnet'),
+        STELLAR_HORIZON_URL: Joi.string().uri().optional(),
+
+        // ── Contract registry limits ─────────────────────────────────
+        CONTRACT_REGISTRY_MAX_ENTRIES: Joi.number().integer().min(1).default(1000),
+        CONTRACT_SCHEMA_VERSION: Joi.string()
+          .pattern(/^\d+\.\d+\.\d+$/)
+          .default('1.0.0'),
+        CONTRACT_REPLAY_MAX_EVENTS: Joi.number().integer().min(1).max(10000).default(1000),
+        CONTRACT_EVENT_RETENTION_DAYS: Joi.number().integer().min(1).max(365).default(90),
+        }),
+      ),
+      cache: true,
+      envFilePath: ['.env.local', '.env'],
+      expandVariables: true,
+      validationOptions: {
+        // Report every invalid variable at once and coerce string env
+        // values to their declared types (numbers, booleans, lists, JSON).
+        abortEarly: false,
+        allowUnknown: true,
+        convert: true,
+      },
       validationSchema: envSchema,
     }),
   ],

BackendAcademy/src/config/env.schema.ts

@@ -23,6 +23,205 @@ export const envSchema = Joi.object({
   REDIS_PORT: Joi.number()
     .integer()
     .min(1)
+    .max(365)
+    .default(90)
+    .description('Number of days to retain contract event logs for replay.'),
+
+  // ── Attachment scanning configuration — Issue #365 ──────────────
+  /** Maximum allowed attachment file size in bytes */
+  MAX_ATTACHMENT_SIZE_BYTES: Joi.number()
+    .integer()
+    .min(1)
+    .default(10_485_760)
+    .description('Maximum allowed attachment file size in bytes (default: 10 MB).'),
+
+  /** Comma-separated list of allowed MIME types for attachments */
+  ALLOWED_ATTACHMENT_TYPES: Joi.string()
+    .optional()
+    .description(
+      'Comma-separated list of allowed MIME types for submission attachments. ' +
+        'Example: "application/pdf,image/png,text/plain"',
+    ),
+
+  /** Whether attachment content policy scanning is enabled */
+  ATTACHMENT_SCANNING_ENABLED: Joi.string()
+    .valid('true', 'false')
+    .default('true')
+    .description('When "true", submission attachments are scanned for policy violations.'),
+
+  // ── Readiness probe configuration — Issue #376 ──────────────────
+  /** Timeout for readiness probe checks in milliseconds */
+  READINESS_PROBE_TIMEOUT_MS: Joi.number()
+    .integer()
+    .min(100)
+    .default(5_000)
+    .description('Timeout for readiness probe dependency checks in milliseconds.'),
+
+  // ── Task orchestrator configuration — Issue #364 ────────────────
+  /** Maximum retries for task orchestration */
+  TASK_ORCHESTRATOR_MAX_RETRIES: Joi.number()
+    .integer()
+    .min(0)
+    .default(3)
+    .description('Maximum number of retry attempts for scheduled tasks.'),
+
+  /** Base backoff time in milliseconds for task retries */
+  TASK_ORCHESTRATOR_BASE_BACKOFF_MS: Joi.number()
+    .integer()
+    .min(100)
+    .default(1_000)
+    .description('Base backoff time in milliseconds before task retries.'),
+
+  /** Maximum backoff time in milliseconds for task retries */
+  TASK_ORCHESTRATOR_MAX_BACKOFF_MS: Joi.number()
+    .integer()
+    .min(100)
+    .default(30_000)
+    .description('Maximum backoff time in milliseconds for task retries.'),
+});
+
+/**
+ * Type derived from the contract env schema validation.
+ */
+export const jobEnvSchema = Joi.object({
+  MAX_JOB_RETRIES: Joi.number().integer().min(0).max(10).default(3)
+    .description('Maximum number of retries for background jobs before sending to DLQ'),
+
+  JOB_RETRY_DELAY_MS: Joi.number().integer().min(100).default(5000)
+    .description('Delay in milliseconds between job retries'),
+
+  DLQ_TTL_SECONDS: Joi.number().integer().min(60).default(604800)
+    .description('TTL in seconds for dead-letter queue records (default: 7 days)'),
+
+  EXPORT_NOTIFICATION_ENABLED: Joi.boolean().default(true)
+    .description('Enable email notifications when exports/reports are ready'),
+
+  EXPORT_RETRY_MAX: Joi.number().integer().min(0).max(10).default(3)
+    .description('Maximum retry attempts for export generation jobs'),
+
+  SIGNED_URL_TTL_SECONDS: Joi.number().integer().min(60).max(86400).default(3600)
+    .description('TTL in seconds for signed download URLs (default: 1 hour)'),
+});
+
+export type JobEnvConfig = {
+  MAX_JOB_RETRIES: number;
+  JOB_RETRY_DELAY_MS: number;
+  DLQ_TTL_SECONDS: number;
+  EXPORT_NOTIFICATION_ENABLED: boolean;
+  EXPORT_RETRY_MAX: number;
+  SIGNED_URL_TTL_SECONDS: number;
+};
+
+export type ContractEnvConfig = {
+  CERTIFICATE_BASE_URL: string;
+  CONTRACT_INGESTION_ENABLED: string;
+  CONTRACT_REGISTRY_REQUIRE_SCHEMA: string;
+  CONTRACT_EVENT_REPLAY_ENABLED: string;
+  CONTRACT_ADAPTER_MODE: string;
+  CONTRACT_NETWORK: string;
+  STELLAR_HORIZON_URL?: string;
+  CONTRACT_REGISTRY_MAX_ENTRIES: number;
+  CONTRACT_SCHEMA_VERSION: string;
+  CONTRACT_REPLAY_MAX_EVENTS: number;
+  CONTRACT_EVENT_RETENTION_DAYS: number;
+  MAX_ATTACHMENT_SIZE_BYTES: number;
+  ALLOWED_ATTACHMENT_TYPES?: string;
+  ATTACHMENT_SCANNING_ENABLED: string;
+  READINESS_PROBE_TIMEOUT_MS: number;
+  TASK_ORCHESTRATOR_MAX_RETRIES: number;
+  TASK_ORCHESTRATOR_BASE_BACKOFF_MS: number;
+  TASK_ORCHESTRATOR_MAX_BACKOFF_MS: number;
+};
+
+/**
+ * Resolves whether a feature flag string is explicitly enabled.
+ * Only the literal string "true" qualifies as enabled.
+ */
+export function isFeatureEnabled(value: string | undefined): boolean {
+  return value === 'true';
+}
+
+/**
+ * Resolves whether a feature flag string is explicitly disabled.
+ * Only the literal string "false" qualifies as explicitly disabled.
+ * Any other value (or absence) is considered misconfigured.
+ */
+export function isFeatureExplicitlyDisabled(value: string | undefined): boolean {
+  return value === 'false';
+}
+
+/**
+ * Environment variables for notification delivery and preferences (#385).
+ */
+export const notificationEnvSchema = Joi.object({
+ * Environment variables for notification delivery and preferences.
+ */
+export const notificationEnvSchema = Joi.object({
+  /** When "true", user notification preferences are enforced before delivery */
+  NOTIFICATION_ENFORCE_PREFERENCES: Joi.string()
+    .valid('true', 'false')
+    .default('true')
+    .description(
+      'When "true", notification delivery checks user preferences first. ' +
+        'Set to "false" to bypass preference checks for critical system alerts.',
+    ),
+  NOTIFICATION_DEFAULT_CHANNEL: Joi.string()
+    .valid('email', 'push', 'in-app', 'all')
+    .default('all')
+    .description('Default notification channel for users without explicit preferences.'),
+});
+
+/**
+ * Combined validation schema that includes contract and notification
+ * environment variables. Used by config.module.ts at startup.
+ */
+export const validationSchema = baseEnvSchema
+  .concat(contractEnvSchema)
+ * Environment variables for migration safety and ordering.
+ */
+export const migrationEnvSchema = Joi.object({
+  /** Timeout in milliseconds for acquiring a migration lock */
+  MIGRATION_LOCK_TIMEOUT: Joi.number()
+    .integer()
+    .min(1000)
+    .default(300_000)
+    .description('Timeout in ms for acquiring a migration lock (default 5 min).'),
+
+  /** Maximum number of retry attempts for failed migrations */
+  MIGRATION_RETRY_ATTEMPTS: Joi.number()
+    .integer()
+    .min(0)
+    .max(10)
+    .default(3)
+    .description('Maximum retry attempts for failed migrations.'),
+
+  /** When true, strict ordering is enforced and migrations out of order are rejected */
+  MIGRATION_STRICT_ORDERING: Joi.string()
+    .valid('true', 'false')
+    .default('true')
+    .description(
+      'When "true", migrations must be applied strictly in dependency order. ' +
+        'Any ordering violation blocks migration execution.',
+    ),
+
+  /** When true, a preflight check is required before any migration can run */
+  MIGRATION_REQUIRE_PREFLIGHT: Joi.string()
+    .valid('true', 'false')
+    .default('true')
+    .description(
+      'When "true", preflight validation must pass before migrations execute.',
+    ),
+});
+
+/**
+ * Combined validation schema that includes base, contract, migration,
+ * and notification environment variables.
+ * Used by config.module.ts to validate all env vars at startup.
+ */
+export const validationSchema = baseEnvSchema
+  .concat(contractEnvSchema)
+  .concat(migrationEnvSchema)
+  .concat(notificationEnvSchema);
     .max(65535)
     .default(6379)
     .description('Redis port number'),

BackendAcademy/src/database/database.service.ts

@@ -150,6 +150,20 @@ export class DatabaseService implements OnModuleInit {
     sample.forEach((c) => this.coupons.set(c.id, c));
   }
 
+  // ---------------------------------------------------------------------
+  // Health check — Issue #375
+  // ---------------------------------------------------------------------
+
+  /**
+   * Returns true when the database (in-memory store) is operational.
+   */
+  async isHealthy(): Promise<boolean> {
+    // The in-memory store is always healthy as long as the process runs.
+    // In production, this would verify actual DB connectivity (e.g.,
+    // SELECT 1 or a connection pool ping).
+    return true;
+  }
+
   async createCoupon(coupon: CouponRecord): Promise<CouponRecord> {
     this.coupons.set(coupon.id, coupon);
     return coupon;