Make sure that the unique databases names generated by TestDatabases.create() don't collide

Signed-off-by: Oliver Sand <oliver.sand@sda-se.com>

.changeset/chilled-schools-raise.md

@@ -0,0 +1,6 @@
+---
+'@backstage/backend-test-utils': patch
+---
+
+Make sure that the unique databases names generated by `TestDatabases.create()`
+don't collide.

packages/backend-test-utils/src/database/TestDatabases.test.ts

@@ -71,7 +71,7 @@ describe('TestDatabases', () => {
         await input.insert({ x: 'y' }).into('a');
 
         // Look for the mark
-        const database = 'backstage_plugin_db0';
+        const database = input.client.config.connection.database;
         const output = knexFactory({
           client: 'pg',
           connection: { host, port, user, password, database },
@@ -105,7 +105,7 @@ describe('TestDatabases', () => {
         await input.insert({ x: 'y' }).into('a');
 
         // Look for the mark
-        const database = 'backstage_plugin_db0';
+        const database = input.client.config.connection.database;
         const output = knexFactory({
           client: 'pg',
           connection: { host, port, user, password, database },
@@ -139,7 +139,7 @@ describe('TestDatabases', () => {
         await input.insert({ x: 'y' }).into('a');
 
         // Look for the mark
-        const database = 'backstage_plugin_db0';
+        const database = input.client.config.connection.database;
         const output = knexFactory({
           client: 'mysql2',
           connection: { host, port, user, password, database },

packages/backend-test-utils/src/database/TestDatabases.ts

@@ -16,6 +16,7 @@
 
 import { DatabaseManager } from '@backstage/backend-common';
 import { ConfigReader } from '@backstage/config';
+import { randomBytes } from 'crypto';
 import { Knex } from 'knex';
 import { isDockerDisabledForTests } from '../util/isDockerDisabledForTests';
 import { startMysqlContainer } from './startMysqlContainer';
@@ -34,7 +35,6 @@ import {
 export class TestDatabases {
   private readonly instanceById: Map<string, Instance>;
   private readonly supportedIds: TestDatabaseId[];
-  private lastDatabaseIndex: number;
 
   /**
    * Creates an empty `TestDatabases` instance, and sets up Jest to clean up
@@ -99,7 +99,6 @@ export class TestDatabases {
   private constructor(supportedIds: TestDatabaseId[]) {
     this.instanceById = new Map();
     this.supportedIds = supportedIds;
-    this.lastDatabaseIndex = 0;
   }
 
   supports(id: TestDatabaseId): boolean {
@@ -142,7 +141,7 @@ export class TestDatabases {
 
     // Ensure that a unique logical database is created in the instance
     const connection = await instance.databaseManager
-      .forPlugin(String(`db${this.lastDatabaseIndex++}`))
+      .forPlugin(`db${randomBytes(16).toString('hex')}`)
       .getClient();
 
     instance.connections.push(connection);