feat: validate backend runtime configuration

backend/apps/api/src/api.module.ts

@@ -1,9 +1,10 @@
 import { Module } from '@nestjs/common';
+import { ConfigurationModule } from '../../../libs/configuration/src';
 import { AppController } from './app.controller';
 import { AppService } from './app.service';
 
 @Module({
-  imports: [],
+  imports: [ConfigurationModule],
   controllers: [AppController],
   providers: [AppService],
 })

backend/apps/api/test/jest-e2e.json

@@ -3,6 +3,7 @@
   "rootDir": "../../..",
   "testEnvironment": "node",
   "testRegex": "apps/api/test/.*\\.e2e-spec\\.ts$",
+  "setupFiles": ["<rootDir>/test/setup-env.ts"],
   "transform": {
     "^.+\\.(t|j)s$": "ts-jest"
   }

backend/apps/api/tsconfig.app.json

@@ -1,8 +1,7 @@
 {
   "extends": "../../tsconfig.json",
   "compilerOptions": {
-    "declaration": false,
-    "outDir": "../../dist/apps/api"
+    "declaration": false
   },
   "exclude": ["node_modules", "dist", "test", "**/*.spec.ts"]
 }

backend/apps/worker/src/worker.module.ts

@@ -1,4 +1,7 @@
 import { Module } from '@nestjs/common';
+import { ConfigurationModule } from '../../../libs/configuration/src';
 
-@Module({})
+@Module({
+  imports: [ConfigurationModule],
+})
 export class WorkerModule {}

backend/apps/worker/tsconfig.app.json

@@ -1,8 +1,7 @@
 {
   "extends": "../../tsconfig.json",
   "compilerOptions": {
-    "declaration": false,
-    "outDir": "../../dist/apps/worker"
+    "declaration": false
   },
   "exclude": ["node_modules", "dist", "test", "**/*.spec.ts"]
 }

backend/libs/configuration/src/configuration.module.ts

@@ -0,0 +1,9 @@
+import { Global, Module } from '@nestjs/common';
+import { appEnvironmentProvider } from './environment';
+
+@Global()
+@Module({
+  providers: [appEnvironmentProvider],
+  exports: [appEnvironmentProvider],
+})
+export class ConfigurationModule {}

backend/libs/configuration/src/environment.spec.ts

@@ -0,0 +1,25 @@
+import { loadEnvironment } from './environment';
+
+describe('loadEnvironment', () => {
+  it('requires database and redis URLs', () => {
+    expect(() => loadEnvironment({})).toThrow('DATABASE_URL');
+  });
+
+  it('returns build metadata without secrets', () => {
+    expect(
+      loadEnvironment({
+        DATABASE_URL: 'postgresql://u:p@postgres:5432/db',
+        REDIS_URL: 'redis://redis:6379',
+        APP_VERSION: '1.2.3',
+        TEAMCITY_BUILD_NUMBER: '42',
+        SOURCE_REVISION: 'abc123',
+      }),
+    ).toEqual({
+      databaseUrl: 'postgresql://u:p@postgres:5432/db',
+      redisUrl: 'redis://redis:6379',
+      appVersion: '1.2.3',
+      teamCityBuildNumber: '42',
+      sourceRevision: 'abc123',
+    });
+  });
+});

backend/libs/configuration/src/environment.ts

@@ -0,0 +1,30 @@
+export interface AppEnvironment {
+  databaseUrl: string;
+  redisUrl: string;
+  appVersion: string;
+  teamCityBuildNumber: string;
+  sourceRevision: string;
+}
+
+function required(env: NodeJS.ProcessEnv, name: string): string {
+  const value = env[name]?.trim();
+  if (!value) throw new Error(`Missing required environment variable: ${name}`);
+  return value;
+}
+
+export function loadEnvironment(env: NodeJS.ProcessEnv): AppEnvironment {
+  return {
+    databaseUrl: required(env, 'DATABASE_URL'),
+    redisUrl: required(env, 'REDIS_URL'),
+    appVersion: env.APP_VERSION?.trim() || 'dev',
+    teamCityBuildNumber: env.TEAMCITY_BUILD_NUMBER?.trim() || 'local',
+    sourceRevision: env.SOURCE_REVISION?.trim() || 'local',
+  };
+}
+
+export const APP_ENVIRONMENT = Symbol('APP_ENVIRONMENT');
+
+export const appEnvironmentProvider = {
+  provide: APP_ENVIRONMENT,
+  useFactory: () => loadEnvironment(process.env),
+};

backend/libs/configuration/src/index.ts

@@ -0,0 +1,2 @@
+export * from './environment';
+export * from './configuration.module';

backend/nest-cli.json

@@ -5,7 +5,7 @@
   "root": "apps/api",
   "sourceRoot": "apps/api/src",
   "compilerOptions": {
-    "deleteOutDir": true
+    "deleteOutDir": false
   },
   "projects": {
     "api": {

backend/package.json

@@ -13,8 +13,8 @@
     "start": "nest start api",
     "start:dev": "nest start api --watch",
     "start:debug": "nest start api --debug --watch",
-    "start:api": "node dist/apps/api/main.js",
-    "start:worker": "node dist/apps/worker/main.js",
+    "start:api": "node dist/apps/api/src/main.js",
+    "start:worker": "node dist/apps/worker/src/main.js",
     "lint": "eslint \"{apps,libs}/**/*.ts\" --fix",
     "test": "jest --runInBand",
     "test:watch": "jest --watch",
@@ -63,13 +63,10 @@
     "rootDir": ".",
     "testRegex": ".*\\.spec\\.ts$",
     "testPathIgnorePatterns": ["<rootDir>/node_modules/", "<rootDir>/dist/"],
+    "setupFiles": ["<rootDir>/test/setup-env.ts"],
     "transform": {
       "^.+\\.(t|j)s$": "ts-jest"
     },
-    "moduleNameMapper": {
-      "^@travel/configuration$": "<rootDir>/libs/configuration/src",
-      "^@travel/infrastructure$": "<rootDir>/libs/infrastructure/src"
-    },
     "collectCoverageFrom": [
       "apps/**/*.(t|j)s",
       "libs/**/*.(t|j)s"

backend/test/setup-env.ts

@@ -0,0 +1,2 @@
+process.env.DATABASE_URL ??= 'postgresql://test:test@localhost:5432/test';
+process.env.REDIS_URL ??= 'redis://localhost:6379';

backend/tsconfig.json

@@ -13,6 +13,7 @@
     "target": "ES2023",
     "sourceMap": true,
     "outDir": "./dist",
+    "rootDir": ".",
     "baseUrl": "./",
     "incremental": true,
     "skipLibCheck": true,
@@ -20,10 +21,6 @@
     "forceConsistentCasingInFileNames": true,
     "noImplicitAny": false,
     "strictBindCallApply": false,
-    "noFallthroughCasesInSwitch": false,
-    "paths": {
-      "@travel/configuration": ["libs/configuration/src"],
-      "@travel/infrastructure": ["libs/infrastructure/src"]
-    }
+    "noFallthroughCasesInSwitch": false
   }
 }