chore: Create test db from template (#9265)

## About the changes
Based on the first hypothesis from
#9264, I decided to find an
alternative way of initializing the DB, mainly trying to run migrations
only once and removing that from the actual test run.

I found in [Postgres template
databases](https://www.postgresql.org/docs/current/manage-ag-templatedbs.html)
an interesting option in combination with jest global initializer.

### Changes on how we use DBs for testing

Previously, we were relying on a single DB with multiple schemas to
isolate tests, but each schema was empty and required migrations or
custom DB initialization scripts.

With this method, we don't need to use different schema names
(apparently there's no templating for schemas), and we can use new
databases. We can also eliminate custom initialization code.

### Legacy tests

This method also highlighted some wrong assumptions in existing tests.
One example is the existence of `default` environment, that because of
being deprecated is no longer available, but because tests are creating
the expected db state manually, they were not updated to match the
existing db state.

To keep tests running green, I've added a configuration to use the
`legacy` test setup (24 tests). By migrating these, we'll speed up
tests, but the code of these tests has to be modified, so I leave this
for another PR.

## Downsides
1. The template db initialization happens at the beginning of any test,
so local development may suffer from slower unit tests. As a workaround
we could define an environment variable to disable the db migration
2. Proliferation of test dbs. In ephemeral environments, this is not a
problem, but for local development we should clean up from time to time.
There's the possibility of cleaning up test dbs using the db name as a
pattern:
https://github.com/Unleash/unleash/blob/2ed2e1c27418b92e815d06c351504005cf083fd0/scripts/jest-setup.ts#L13-L18
but I didn't want to add this code yet. Opinions?

## Benefits
1. It allows us migrate only once and still get the benefits of having a
well known state for tests.
3. It removes some of the custom setup for tests (which in some cases
ends up testing something not realistic)
4. It removes the need of testing migrations:
https://github.com/Unleash/unleash/blob/main/src/test/e2e/migrator.e2e.test.ts
as migrations are run at the start
5. Forces us to keep old tests up to date when we modify our database

Author: gastonfournier

package.json

@@ -57,9 +57,9 @@
     "test:report": "NODE_ENV=test PORT=4243 jest --reporters=\"default\" --reporters=\"jest-junit\"",
     "test:docker:cleanup": "docker rm -f unleash-postgres",
     "test:watch": "yarn test --watch",
-    "test:coverage": "NODE_ENV=test PORT=4243 jest --coverage --testLocationInResults --outputFile=\"coverage/report.json\" --forceExit --testTimeout=10000",
-    "test:coverage:jest": "NODE_ENV=test PORT=4243 jest --silent --ci --json --coverage --testLocationInResults --outputFile=\"report.json\" --forceExit --testTimeout=10000",
-    "test:updateSnapshot": "NODE_ENV=test PORT=4243 jest --updateSnapshot --testTimeout=10000",
+    "test:coverage": "NODE_ENV=test PORT=4243 jest --coverage --testLocationInResults --outputFile=\"coverage/report.json\" --forceExit",
+    "test:coverage:jest": "NODE_ENV=test PORT=4243 jest --silent --ci --json --coverage --testLocationInResults --outputFile=\"report.json\" --forceExit",
+    "test:updateSnapshot": "NODE_ENV=test PORT=4243 jest --updateSnapshot",
     "seed:setup": "ts-node --compilerOptions '{\"strictNullChecks\": false}' src/test/e2e/seed/segment.seed.ts",
     "seed:serve": "UNLEASH_DATABASE_NAME=unleash_test UNLEASH_DATABASE_SCHEMA=seed yarn run start:dev",
     "clean": "del-cli --force dist",
@@ -81,7 +81,7 @@
     "automock": false,
     "maxWorkers": 4,
     "testTimeout": 20000,
-    "globalSetup": "./scripts/jest-setup.js",
+    "globalSetup": "./scripts/jest-setup.ts",
     "transform": {
       "^.+\\.tsx?$": [
         "@swc/jest"

scripts/jest-setup.js

@@ -0,0 +1,35 @@
+import { Client, type ClientConfig } from 'pg';
+import { migrateDb } from '../src/migrator';
+import { getDbConfig } from '../src/test/e2e/helpers/database-config';
+
+let initializationPromise: Promise<void> | null = null;
+const initializeTemplateDb = (db: ClientConfig): Promise<void> => {
+    if (!initializationPromise) {
+        initializationPromise = (async () => {
+            const testDBTemplateName = process.env.TEST_DB_TEMPLATE_NAME;
+            const client = new Client(db);
+            await client.connect();
+            console.log(`Initializing template database ${testDBTemplateName}`);
+            // code to clean up, but only on next run, we could do it at tear down... but is it really needed?
+            // const result = await client.query(`select datname from pg_database where datname like 'unleashtestdb_%';`)
+            // result.rows.forEach(async (row: any) => {
+            //     console.log(`Dropping test database ${row.datname}`);
+            //     await client.query(`DROP DATABASE ${row.datname}`);
+            // });
+            await client.query(`DROP DATABASE IF EXISTS ${testDBTemplateName}`);
+            await client.query(`CREATE DATABASE ${testDBTemplateName}`);
+            await client.end();
+            await migrateDb({
+                db: { ...db, database: testDBTemplateName },
+            } as any);
+            console.log(`Template database ${testDBTemplateName} migrated`);
+        })();
+    }
+    return initializationPromise;
+};
+
+export default async function globalSetup() {
+    process.env.TZ = 'UTC';
+    process.env.TEST_DB_TEMPLATE_NAME = 'unleash_template_db';
+    await initializeTemplateDb(getDbConfig());
+}

scripts/jest-setup.ts

@@ -31,7 +31,7 @@ test(`Should indicate change request enabled status`, async () => {
     // change request enabled in enabled environment
     await db.rawDatabase('change_request_settings').insert({
         project: 'default',
-        environment: 'default',
+        environment: 'development',
         required_approvals: 1,
     });
     const enabledStatus =
@@ -41,7 +41,7 @@ test(`Should indicate change request enabled status`, async () => {
     // change request enabled in disabled environment
     await db.stores.projectStore.deleteEnvironmentForProject(
         'default',
-        'default',
+        'development',
     );
     const disabledStatus =
         await readModel.isChangeRequestsEnabledForProject('default');

src/lib/features/change-request-access-service/sql-change-request-access-read-model.test.ts

@@ -19,7 +19,9 @@ let db: ITestDb;
 let eventStore: IEventStore;
 
 beforeAll(async () => {
-    db = await dbInit('dependent_features', getLogger);
+    db = await dbInit('dependent_features', getLogger, {
+        dbInitMethod: 'legacy' as const,
+    });
     app = await setupAppWithCustomConfig(
         db.stores,
         {

src/lib/features/dependent-features/dependent.features.e2e.test.ts

@@ -27,7 +27,9 @@ let eventBus: EventEmitter;
 let featureLifecycleReadModel: IFeatureLifecycleReadModel;
 
 beforeAll(async () => {
-    db = await dbInit('feature_lifecycle', getLogger);
+    db = await dbInit('feature_lifecycle', getLogger, {
+        dbInitMethod: 'legacy' as const,
+    });
     app = await setupAppWithAuth(
         db.stores,
         {

src/lib/features/feature-lifecycle/feature-lifecycle.e2e.test.ts

@@ -19,7 +19,9 @@ let db: ITestDb;
 let stores: IUnleashStores;
 
 beforeAll(async () => {
-    db = await dbInit('feature_search', getLogger);
+    db = await dbInit('feature_search', getLogger, {
+        dbInitMethod: 'legacy' as const,
+    });
     app = await setupAppWithAuth(
         db.stores,
         {

src/lib/features/feature-search/feature.search.e2e.test.ts

@@ -11,7 +11,9 @@ let app: IUnleashTest;
 let db: ITestDb;
 
 beforeAll(async () => {
-    db = await dbInit('archive_test_serial', getLogger);
+    db = await dbInit('archive_test_serial', getLogger, {
+        dbInitMethod: 'legacy' as const,
+    });
     app = await setupAppWithCustomConfig(
         db.stores,
         {

src/lib/features/feature-toggle/tests/archive-feature-toggles.e2e.test.ts

@@ -7,20 +7,20 @@ import {
     setupAppWithCustomConfig,
 } from '../../../../test/e2e/helpers/test-helper';
 import getLogger from '../../../../test/fixtures/no-logger';
+import type { IUnleashOptions } from '../../../internals';
 
 let app: IUnleashTest;
 let db: ITestDb;
 
 const setupLastSeenAtTest = async (featureName: string) => {
     await app.createFeature(featureName);
 
-    await insertLastSeenAt(featureName, db.rawDatabase, 'default');
     await insertLastSeenAt(featureName, db.rawDatabase, 'development');
     await insertLastSeenAt(featureName, db.rawDatabase, 'production');
 };
 
 beforeAll(async () => {
-    const config = {
+    const config: Partial<IUnleashOptions> = {
         experimental: {
             flags: {
                 strictSchemaValidation: true,
@@ -34,29 +34,6 @@ beforeAll(async () => {
         config,
     );
     app = await setupAppWithCustomConfig(db.stores, config, db.rawDatabase);
-
-    await db.stores.environmentStore.create({
-        name: 'development',
-        type: 'development',
-        sortOrder: 1,
-        enabled: true,
-    });
-
-    await db.stores.environmentStore.create({
-        name: 'production',
-        type: 'production',
-        sortOrder: 2,
-        enabled: true,
-    });
-
-    await app.services.projectService.addEnvironmentToProject(
-        'default',
-        'development',
-    );
-    await app.services.projectService.addEnvironmentToProject(
-        'default',
-        'production',
-    );
 });
 
 afterAll(async () => {
@@ -67,7 +44,7 @@ afterAll(async () => {
 test('should return last seen at per env for /api/admin/features', async () => {
     await app.createFeature('lastSeenAtPerEnv');
 
-    await insertLastSeenAt('lastSeenAtPerEnv', db.rawDatabase, 'default');
+    await insertLastSeenAt('lastSeenAtPerEnv', db.rawDatabase, 'development');
 
     const response = await app.request
         .get('/api/admin/projects/default/features')
@@ -94,10 +71,7 @@ test('response should include last seen at per environment for multiple environm
 
     const featureEnvironments = body.features[1].environments;
 
-    const [def, development, production] = featureEnvironments;
-
-    expect(def.name).toBe('default');
-    expect(def.lastSeenAt).toEqual('2023-10-01T12:34:56.000Z');
+    const [development, production] = featureEnvironments;
 
     expect(development.name).toBe('development');
     expect(development.lastSeenAt).toEqual('2023-10-01T12:34:56.000Z');
@@ -117,10 +91,7 @@ test('response should include last seen at per environment for multiple environm
     const { body } = await app.request.get(`/api/admin/archive/features`);
 
     const featureEnvironments = body.features[0].environments;
-    const [def, development, production] = featureEnvironments;
-
-    expect(def.name).toBe('default');
-    expect(def.lastSeenAt).toEqual('2023-10-01T12:34:56.000Z');
+    const [development, production] = featureEnvironments;
 
     expect(development.name).toBe('development');
     expect(development.lastSeenAt).toEqual('2023-10-01T12:34:56.000Z');
@@ -142,10 +113,7 @@ test('response should include last seen at per environment for multiple environm
     );
 
     const featureEnvironments = body.features[0].environments;
-    const [def, development, production] = featureEnvironments;
-
-    expect(def.name).toBe('default');
-    expect(def.lastSeenAt).toEqual('2023-10-01T12:34:56.000Z');
+    const [development, production] = featureEnvironments;
 
     expect(development.name).toBe('development');
     expect(development.lastSeenAt).toEqual('2023-10-01T12:34:56.000Z');
@@ -163,13 +131,6 @@ test('response should include last seen at per environment correctly for a singl
     await setupLastSeenAtTest(`${featureName}4`);
     await setupLastSeenAtTest(`${featureName}5`);
 
-    await insertLastSeenAt(
-        featureName,
-        db.rawDatabase,
-        'default',
-        '2023-08-01T12:30:56.000Z',
-    );
-
     await insertLastSeenAt(
         featureName,
         db.rawDatabase,
@@ -189,10 +150,6 @@ test('response should include last seen at per environment correctly for a singl
         .expect(200);
 
     const expected = [
-        {
-            name: 'default',
-            lastSeenAt: '2023-08-01T12:30:56.000Z',
-        },
         {
             name: 'development',
             lastSeenAt: '2023-08-01T12:30:56.000Z',

src/lib/features/feature-toggle/tests/feature-toggle-last-seen-at.e2e.test.ts

@@ -55,6 +55,7 @@ beforeAll(async () => {
     db = await dbInit(
         'feature_toggle_service_v2_service_serial',
         config.getLogger,
+        { dbInitMethod: 'legacy' as const },
     );
     unleashConfig = config;
     stores = db.stores;

src/lib/features/feature-toggle/tests/feature-toggle-service.e2e.test.ts

@@ -17,7 +17,9 @@ let app: IUnleashTest;
 let db: ITestDb;
 
 beforeAll(async () => {
-    db = await dbInit('feature_strategy_auth_api_serial', getLogger);
+    db = await dbInit('feature_strategy_auth_api_serial', getLogger, {
+        dbInitMethod: 'legacy' as const,
+    });
     app = await setupAppWithAuth(
         db.stores,
         {

src/lib/features/feature-toggle/tests/feature-toggles.auth.e2e.test.ts

@@ -92,7 +92,9 @@ const updateStrategy = async (
 };
 
 beforeAll(async () => {
-    db = await dbInit('feature_strategy_api_serial', getLogger);
+    db = await dbInit('feature_strategy_api_serial', getLogger, {
+        dbInitMethod: 'legacy' as const,
+    });
     app = await setupAppWithCustomConfig(
         db.stores,
         {

src/lib/features/feature-toggle/tests/feature-toggles.e2e.test.ts

@@ -23,7 +23,9 @@ let app: IUnleashTest;
 let db: ITestDb;
 let frontendApiService: FrontendApiService;
 beforeAll(async () => {
-    db = await dbInit('frontend_api', getLogger);
+    db = await dbInit('frontend_api', getLogger, {
+        dbInitMethod: 'legacy' as const,
+    });
     app = await setupAppWithAuth(
         db.stores,
         {

src/lib/features/frontend-api/frontend-api.e2e.test.ts

@@ -44,12 +44,6 @@ const noEnvironmentEvent = (days: number) => {
 
 beforeAll(async () => {
     db = await dbInit('product_changes_serial', getLogger);
-    await db.rawDatabase('environments').insert({
-        name: 'production',
-        type: 'production',
-        enabled: true,
-        protected: false,
-    });
     getProductionChanges = createGetProductionChanges(db.rawDatabase);
 });
 
@@ -136,12 +130,6 @@ test('five events per day should be counted correctly', async () => {
 });
 
 test('Events posted to a non production environment should not be included in count', async () => {
-    await db.rawDatabase('environments').insert({
-        name: 'development',
-        type: 'development',
-        enabled: true,
-        protected: false,
-    });
     await db.rawDatabase
         .table('events')
         .insert(mockRawEventDaysAgo(1, 'development'));

src/lib/features/instance-stats/getProductionChanges.e2e.test.ts

@@ -357,12 +357,6 @@ describe('bulk metrics', () => {
                 enableApiToken: true,
             },
         });
-        await authed.db('environments').insert({
-            name: 'development',
-            sort_order: 5000,
-            type: 'development',
-            enabled: true,
-        });
         const clientToken =
             await authed.services.apiTokenService.createApiTokenWithProjects({
                 tokenName: 'bulk-metrics-test',

src/lib/features/metrics/instance/metrics.test.ts

@@ -10,7 +10,9 @@ let app: IUnleashTest;
 let db: ITestDb;
 
 beforeAll(async () => {
-    db = await dbInit('advanced_playground', getLogger);
+    db = await dbInit('advanced_playground', getLogger, {
+        dbInitMethod: 'legacy' as const,
+    });
     app = await setupAppWithCustomConfig(
         db.stores,
         {

src/lib/features/playground/advanced-playground.test.ts

@@ -18,7 +18,9 @@ let eventService: EventService;
 
 beforeAll(async () => {
     const config = createTestConfig();
-    db = await dbInit('environment_service_serial', config.getLogger);
+    db = await dbInit('environment_service_serial', config.getLogger, {
+        dbInitMethod: 'legacy' as const,
+    });
     stores = db.stores;
     eventService = createEventsService(db.rawDatabase, config);
     service = new EnvironmentService(stores, config, eventService);

src/lib/features/project-environments/environment-service.test.ts

@@ -10,7 +10,9 @@ let app: IUnleashTest;
 let db: ITestDb;
 
 beforeAll(async () => {
-    db = await dbInit('project_environments_api_serial', getLogger);
+    db = await dbInit('project_environments_api_serial', getLogger, {
+        dbInitMethod: 'legacy' as const,
+    });
     app = await setupAppWithCustomConfig(
         db.stores,
         {

src/lib/features/project-environments/environments.e2e.test.ts

@@ -1274,7 +1274,7 @@ test('A newly created project only gets connected to enabled environments', asyn
     await projectService.createProject(project, user, auditUser);
     const connectedEnvs =
         await db.stores.projectStore.getEnvironmentsForProject(project.id);
-    expect(connectedEnvs).toHaveLength(2); // default, connection_test
+    expect(connectedEnvs).toHaveLength(1); // connection_test
     expect(
         connectedEnvs.some((e) => e.environment === enabledEnv),
     ).toBeTruthy();
@@ -1321,7 +1321,6 @@ test('should have environments sorted in order', async () => {
         await db.stores.projectStore.getEnvironmentsForProject(project.id);
 
     expect(connectedEnvs.map((e) => e.environment)).toEqual([
-        'default',
         first,
         second,
         third,
@@ -2809,13 +2808,7 @@ describe('create project with environments', () => {
         disabledEnv,
     ];
 
-    const allEnabledEnvs = [
-        'QA',
-        'default',
-        'development',
-        'production',
-        'staging',
-    ];
+    const allEnabledEnvs = ['QA', 'development', 'production', 'staging'];
 
     beforeEach(async () => {
         await Promise.all(