fix(gateway): load dotenv before federation tier gate (#1138)

2026-08-09 20:50:37 -05:00
parent b4753a75cd
commit b82a51da80
4 changed files with 114 additions and 15 deletions
@@ -0,0 +1,96 @@
+import 'reflect-metadata';
+import { mkdtemp, mkdir, readFile, rm, writeFile } from 'node:fs/promises';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { MODULE_METADATA } from '@nestjs/common/constants.js';
+import { describe, expect, it, vi } from 'vitest';
+
+interface ComposedModuleGraph {
+  imports: readonly unknown[];
+  federationModule: unknown;
+}
+
+const MODULE_IMPORT_TIMEOUT_MS = 30_000;
+
+function restoreEnvironmentVariable(name: string, value: string | undefined): void {
+  if (value === undefined) {
+    delete process.env[name];
+    return;
+  }
+
+  process.env[name] = value;
+}
+
+async function loadModuleGraphFromDotenv(
+  tier: 'local' | 'standalone' | 'federated',
+): Promise<ComposedModuleGraph> {
+  const originalHome = process.env['HOME'];
+  const originalTier = process.env['MOSAIC_STORAGE_TIER'];
+  const originalDatabaseUrl = process.env['DATABASE_URL'];
+  const fixtureRoot = await mkdtemp(join(tmpdir(), 'mosaic-gateway-module-'));
+  const gatewayCwd = join(fixtureRoot, 'apps', 'gateway');
+
+  await mkdir(gatewayCwd, { recursive: true });
+  await writeFile(join(fixtureRoot, '.env'), `MOSAIC_STORAGE_TIER=${tier}\n`, 'utf8');
+
+  process.env['HOME'] = join(fixtureRoot, 'home');
+  delete process.env['MOSAIC_STORAGE_TIER'];
+  delete process.env['DATABASE_URL'];
+  vi.resetModules();
+  const cwdSpy = vi.spyOn(process, 'cwd').mockReturnValue(gatewayCwd);
+
+  try {
+    expect(process.env['MOSAIC_STORAGE_TIER']).toBeUndefined();
+    await import('./env.js');
+    expect(process.env['MOSAIC_STORAGE_TIER']).toBe(tier);
+
+    const { AppModule } = await import('./app.module.js');
+    const { FederationModule } = await import('./federation/federation.module.js');
+    const imports: unknown = Reflect.getMetadata(MODULE_METADATA.IMPORTS, AppModule);
+
+    if (!Array.isArray(imports)) {
+      throw new Error('AppModule imports metadata is not an array');
+    }
+
+    return { imports, federationModule: FederationModule };
+  } finally {
+    cwdSpy.mockRestore();
+    restoreEnvironmentVariable('HOME', originalHome);
+    restoreEnvironmentVariable('MOSAIC_STORAGE_TIER', originalTier);
+    restoreEnvironmentVariable('DATABASE_URL', originalDatabaseUrl);
+    await rm(fixtureRoot, { recursive: true, force: true });
+  }
+}
+
+describe('AppModule federation gating', (): void => {
+  it('loads dotenv before tracing and AppModule evaluation', async (): Promise<void> => {
+    const mainSource = await readFile(new URL('./main.ts', import.meta.url), 'utf8');
+    const envImportIndex = mainSource.indexOf("import './env.js';");
+    const tracingImportIndex = mainSource.indexOf("import './tracing.js';");
+    const appModuleImportIndex = mainSource.indexOf("import { AppModule } from './app.module.js';");
+
+    expect(envImportIndex).toBeGreaterThan(-1);
+    expect(envImportIndex).toBeLessThan(tracingImportIndex);
+    expect(envImportIndex).toBeLessThan(appModuleImportIndex);
+  });
+
+  it.each(['local', 'standalone'] as const)(
+    'does not register FederationModule for the %s tier',
+    async (tier): Promise<void> => {
+      const graph = await loadModuleGraphFromDotenv(tier);
+
+      expect(graph.imports).not.toContain(graph.federationModule);
+    },
+    MODULE_IMPORT_TIMEOUT_MS,
+  );
+
+  it(
+    'registers FederationModule when federated tier is supplied only by a dotenv file',
+    async (): Promise<void> => {
+      const graph = await loadModuleGraphFromDotenv('federated');
+
+      expect(graph.imports).toContain(graph.federationModule);
+    },
+    MODULE_IMPORT_TIMEOUT_MS,
+  );
+});