From 055b75b39f60406d77b91c39eb05407d7214744b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fredrik=20Adel=C3=B6w?= <freben@gmail.com>
Date: Fri, 30 Aug 2024 13:20:18 +0200
Subject: [PATCH 1/5] remove deprecated exports
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Fredrik Adelöw <freben@gmail.com>
---
 .changeset/wise-forks-play.md                 | 10 ++++++
 packages/backend-common/api-report.md         | 12 +------
 .../backend-common/src/deprecated/index.ts    | 16 +---------
 .../backend-defaults/api-report-database.md   | 14 +-------
 .../entrypoints/database/DatabaseManager.ts   | 32 ++-----------------
 .../src/entrypoints/database/index.ts         |  2 --
 6 files changed, 15 insertions(+), 71 deletions(-)
 create mode 100644 .changeset/wise-forks-play.md

diff --git a/.changeset/wise-forks-play.md b/.changeset/wise-forks-play.md
new file mode 100644
index 0000000000..84a6da9003
--- /dev/null
+++ b/.changeset/wise-forks-play.md
@@ -0,0 +1,10 @@
+---
+'@backstage/backend-common': minor
+'@backstage/backend-defaults': minor
+---
+
+**BREAKING**: Simplifications and cleanup as part of the Backend System 1.0 work.
+
+- The deprecated `dropDatabase` function has now been removed, without replacement.
+- The deprecated `LegacyRootDatabaseService` type has now been removed. The implication is that you now need to pass deps to a `DatabaseManager` when constructing one.
+- The return type from `DatabaseManager.forPlugin` is now directly a `DatabaseService`, as arguably expected.
diff --git a/packages/backend-common/api-report.md b/packages/backend-common/api-report.md
index 7de2731518..2555ab6f5b 100644
--- a/packages/backend-common/api-report.md
+++ b/packages/backend-common/api-report.md
@@ -143,7 +143,7 @@ export function createStatusCheckRouter(options: {
 }): Promise<express.Router>;
 
 // @public @deprecated (undocumented)
-export class DatabaseManager implements LegacyRootDatabaseService {
+export class DatabaseManager {
   // (undocumented)
   forPlugin(
     pluginId: string,
@@ -173,11 +173,6 @@ export class DockerContainerRunner implements ContainerRunner {
   runContainer(options: RunContainerOptions): Promise<void>;
 }
 
-// Warning: (ae-forgotten-export) The symbol "dropDatabase_2" needs to be exported by the entry point index.d.ts
-//
-// @public @deprecated (undocumented)
-export const dropDatabase: typeof dropDatabase_2;
-
 // @public @deprecated
 export function errorHandler(
   options?: ErrorHandlerOptions,
@@ -367,11 +362,6 @@ export const legacyPlugin: (
   }>,
 ) => BackendFeature;
 
-// Warning: (ae-forgotten-export) The symbol "LegacyRootDatabaseService_2" needs to be exported by the entry point index.d.ts
-//
-// @public @deprecated (undocumented)
-export type LegacyRootDatabaseService = LegacyRootDatabaseService_2;
-
 // @public @deprecated
 export function loadBackendConfig(options: {
   logger: LoggerService;
diff --git a/packages/backend-common/src/deprecated/index.ts b/packages/backend-common/src/deprecated/index.ts
index 5dfcd322ed..d34b81aa92 100644
--- a/packages/backend-common/src/deprecated/index.ts
+++ b/packages/backend-common/src/deprecated/index.ts
@@ -30,10 +30,8 @@ import {
 
 // eslint-disable-next-line @backstage/no-relative-monorepo-imports
 import {
-  dropDatabase as _dropDatabase,
   DatabaseManager as _DatabaseManager,
   type DatabaseManagerOptions as _DatabaseManagerOptions,
-  type LegacyRootDatabaseService as _LegacyRootDatabaseService,
 } from '../../../backend-defaults/src/entrypoints/database/DatabaseManager';
 
 import {
@@ -169,7 +167,7 @@ export type CacheClientOptions = CacheServiceOptions;
  * @public
  * @deprecated Use `DatabaseManager` from the `@backstage/backend-defaults` package instead
  */
-export class DatabaseManager implements LegacyRootDatabaseService {
+export class DatabaseManager {
   private constructor(private readonly _databaseManager: _DatabaseManager) {}
 
   static fromConfig(
@@ -202,18 +200,6 @@ export type DatabaseManagerOptions = _DatabaseManagerOptions;
  */
 export type PluginDatabaseManager = _PluginDatabaseManager;
 
-/**
- * @public
- * @deprecated Use `LegacyRootDatabaseService` from the `@backstage/backend-defaults` package instead
- */
-export type LegacyRootDatabaseService = _LegacyRootDatabaseService;
-
-/**
- * @public
- * @deprecated Use `dropDatabase` from the `@backstage/backend-defaults` package instead
- */
-export const dropDatabase = _dropDatabase;
-
 /**
  * @public
  * @deprecated This function is deprecated and will be removed in a future release, see https://github.com/backstage/backstage/issues/24493.
diff --git a/packages/backend-defaults/api-report-database.md b/packages/backend-defaults/api-report-database.md
index 49ffa75ca7..8f3857fe23 100644
--- a/packages/backend-defaults/api-report-database.md
+++ b/packages/backend-defaults/api-report-database.md
@@ -3,7 +3,6 @@
 > Do not edit this file. It is a report generated by [API Extractor](https://api-extractor.com/).
 
 ```ts
-import { Config } from '@backstage/config';
 import { DatabaseService } from '@backstage/backend-plugin-api';
 import { LifecycleService } from '@backstage/backend-plugin-api';
 import { LoggerService } from '@backstage/backend-plugin-api';
@@ -12,7 +11,7 @@ import { RootConfigService } from '@backstage/backend-plugin-api';
 import { ServiceFactory } from '@backstage/backend-plugin-api';
 
 // @public
-export class DatabaseManager implements LegacyRootDatabaseService {
+export class DatabaseManager {
   forPlugin(
     pluginId: string,
     deps?: {
@@ -39,16 +38,5 @@ export const databaseServiceFactory: ServiceFactory<
   'singleton'
 >;
 
-// @public @deprecated
-export function dropDatabase(
-  dbConfig: Config,
-  ...databaseNames: string[]
-): Promise<void>;
-
-// @public
-export type LegacyRootDatabaseService = {
-  forPlugin(pluginId: string): DatabaseService;
-};
-
 // (No @packageDocumentation comment for this package)
 ```
diff --git a/packages/backend-defaults/src/entrypoints/database/DatabaseManager.ts b/packages/backend-defaults/src/entrypoints/database/DatabaseManager.ts
index 88d95443bb..1230280e07 100644
--- a/packages/backend-defaults/src/entrypoints/database/DatabaseManager.ts
+++ b/packages/backend-defaults/src/entrypoints/database/DatabaseManager.ts
@@ -46,18 +46,10 @@ export type DatabaseManagerOptions = {
   logger?: LoggerService;
 };
 
-/**
- * An interface that represents the legacy global DatabaseManager implementation.
- * @public
- */
-export type LegacyRootDatabaseService = {
-  forPlugin(pluginId: string): DatabaseService;
-};
-
 /**
  * Testable implementation class for {@link DatabaseManager} below.
  */
-export class DatabaseManagerImpl implements LegacyRootDatabaseService {
+export class DatabaseManagerImpl {
   constructor(
     private readonly config: Config,
     private readonly connectors: Record<string, Connector>,
@@ -193,7 +185,7 @@ export class DatabaseManagerImpl implements LegacyRootDatabaseService {
  * set `prefix` which is used to prefix generated database names if config is
  * not provided.
  */
-export class DatabaseManager implements LegacyRootDatabaseService {
+export class DatabaseManager {
   /**
    * Creates a {@link DatabaseManager} from `backend.database` config.
    *
@@ -241,23 +233,3 @@ export class DatabaseManager implements LegacyRootDatabaseService {
     return this.impl.forPlugin(pluginId, deps);
   }
 }
-
-/**
- * Helper for deleting databases.
- *
- * @public
- * @deprecated Will be removed in a future release.
- */
-export async function dropDatabase(
-  dbConfig: Config,
-  ...databaseNames: string[]
-): Promise<void> {
-  const client = dbConfig.getString('client');
-  const prefix = dbConfig.getOptionalString('prefix') || 'backstage_plugin_';
-
-  if (client === 'pg') {
-    await new PgConnector(dbConfig, prefix).dropDatabase(...databaseNames);
-  } else if (client === 'mysql' || client === 'mysql2') {
-    await new MysqlConnector(dbConfig, prefix).dropDatabase(...databaseNames);
-  }
-}
diff --git a/packages/backend-defaults/src/entrypoints/database/index.ts b/packages/backend-defaults/src/entrypoints/database/index.ts
index 7d6221b856..e30d06cbdd 100644
--- a/packages/backend-defaults/src/entrypoints/database/index.ts
+++ b/packages/backend-defaults/src/entrypoints/database/index.ts
@@ -18,6 +18,4 @@ export { databaseServiceFactory } from './databaseServiceFactory';
 export {
   DatabaseManager,
   type DatabaseManagerOptions,
-  type LegacyRootDatabaseService,
-  dropDatabase,
 } from './DatabaseManager';

From fd66330d4a375555b4891190cb83805297d12986 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fredrik=20Adel=C3=B6w?= <freben@gmail.com>
Date: Fri, 30 Aug 2024 13:42:38 +0200
Subject: [PATCH 2/5] remove unused DatabaseConnector type
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Fredrik Adelöw <freben@gmail.com>
---
 .../src/entrypoints/database/types.ts         | 65 -------------------
 1 file changed, 65 deletions(-)

diff --git a/packages/backend-defaults/src/entrypoints/database/types.ts b/packages/backend-defaults/src/entrypoints/database/types.ts
index a9cceaa1f9..74f41581f6 100644
--- a/packages/backend-defaults/src/entrypoints/database/types.ts
+++ b/packages/backend-defaults/src/entrypoints/database/types.ts
@@ -18,75 +18,10 @@ import {
   LifecycleService,
   PluginMetadataService,
 } from '@backstage/backend-plugin-api';
-import { Config } from '@backstage/config';
 import { Knex } from 'knex';
 
 export type { DatabaseService as PluginDatabaseManager } from '@backstage/backend-plugin-api';
 
-/**
- * Manages an underlying Knex database driver.
- */
-export interface DatabaseConnector {
-  /**
-   * Provides an instance of a knex database connector.
-   */
-  createClient(
-    dbConfig: Config,
-    overrides?: Partial<Knex.Config>,
-    deps?: {
-      lifecycle: LifecycleService;
-      pluginMetadata: PluginMetadataService;
-    },
-  ): Knex;
-
-  /**
-   * Provides a partial knex config sufficient to override a database name.
-   */
-  createNameOverride(name: string): Partial<Knex.Config>;
-
-  /**
-   * Provides a partial knex config sufficient to override a PostgreSQL schema
-   * name within utilizing the `searchPath` knex configuration.
-   */
-  createSchemaOverride?(name: string): Partial<Knex.Config>;
-
-  /**
-   * Produces a knex connection config object representing a database connection
-   * string.
-   */
-  parseConnectionString(
-    connectionString: string,
-    client?: string,
-  ): Knex.StaticConnectionConfig;
-
-  /**
-   * Performs a side-effect to ensure database names passed in are present.
-   *
-   * Calling this function on databases which already exist should do nothing.
-   * Missing databases should be created if needed.
-   */
-  ensureDatabaseExists?(
-    dbConfig: Config,
-    ...databases: Array<string>
-  ): Promise<void>;
-
-  /**
-   * Performs a side-effect to ensure schema names passed in are present.
-   *
-   * Calling this function on schemas which already exist should do nothing.
-   * Missing schemas should be created if needed.
-   */
-  ensureSchemaExists?(
-    dbConfig: Config,
-    ...schemas: Array<string>
-  ): Promise<void>;
-
-  /**
-   * Deletes databases.
-   */
-  dropDatabase?(dbConfig: Config, ...databases: Array<string>): Promise<void>;
-}
-
 export interface Connector {
   getClient(
     pluginId: string,

From e46754a18b1bcd9e63e3ae6a56b80be3eaf52c7d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fredrik=20Adel=C3=B6w?= <freben@gmail.com>
Date: Fri, 30 Aug 2024 13:46:40 +0200
Subject: [PATCH 3/5] remove the unused dropDatabase in the connector
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Fredrik Adelöw <freben@gmail.com>
---
 .../src/entrypoints/database/DatabaseManager.test.ts        | 6 ------
 .../src/entrypoints/database/connectors/mysql.ts            | 4 ----
 .../src/entrypoints/database/connectors/postgres.ts         | 4 ----
 .../src/entrypoints/database/connectors/sqlite3.ts          | 4 ----
 packages/backend-defaults/src/entrypoints/database/types.ts | 2 --
 5 files changed, 20 deletions(-)

diff --git a/packages/backend-defaults/src/entrypoints/database/DatabaseManager.test.ts b/packages/backend-defaults/src/entrypoints/database/DatabaseManager.test.ts
index 0d52ff16ff..fca6080329 100644
--- a/packages/backend-defaults/src/entrypoints/database/DatabaseManager.test.ts
+++ b/packages/backend-defaults/src/entrypoints/database/DatabaseManager.test.ts
@@ -26,11 +26,9 @@ describe('DatabaseManagerImpl', () => {
   it('calls the right connector, only once per plugin id', async () => {
     const connector1 = {
       getClient: jest.fn(),
-      dropDatabase: jest.fn(),
     } satisfies Connector;
     const connector2 = {
       getClient: jest.fn(),
-      dropDatabase: jest.fn(),
     } satisfies Connector;
 
     const impl = new DatabaseManagerImpl(
@@ -62,11 +60,9 @@ describe('DatabaseManagerImpl', () => {
   it('respects per-plugin overridden connectors', async () => {
     const connector1 = {
       getClient: jest.fn(),
-      dropDatabase: jest.fn(),
     } satisfies Connector;
     const connector2 = {
       getClient: jest.fn(),
-      dropDatabase: jest.fn(),
     } satisfies Connector;
 
     const impl = new DatabaseManagerImpl(
@@ -99,7 +95,6 @@ describe('DatabaseManagerImpl', () => {
   it('migration skip options take precedence over config', async () => {
     const connector = {
       getClient: jest.fn(),
-      dropDatabase: jest.fn(),
     } satisfies Connector;
 
     const impl = new DatabaseManagerImpl(
@@ -133,7 +128,6 @@ describe('DatabaseManagerImpl', () => {
   it('plugin can skip migrations using config', async () => {
     const connector = {
       getClient: jest.fn(),
-      dropDatabase: jest.fn(),
     } satisfies Connector;
 
     const impl = new DatabaseManagerImpl(
diff --git a/packages/backend-defaults/src/entrypoints/database/connectors/mysql.ts b/packages/backend-defaults/src/entrypoints/database/connectors/mysql.ts
index b11b659a6d..f06db5999d 100644
--- a/packages/backend-defaults/src/entrypoints/database/connectors/mysql.ts
+++ b/packages/backend-defaults/src/entrypoints/database/connectors/mysql.ts
@@ -293,10 +293,6 @@ export class MysqlConnector implements Connector {
     return client;
   }
 
-  async dropDatabase(...databaseNames: string[]): Promise<void> {
-    return await dropMysqlDatabase(this.config, ...databaseNames);
-  }
-
   /**
    * Provides the canonical database name for a given plugin.
    *
diff --git a/packages/backend-defaults/src/entrypoints/database/connectors/postgres.ts b/packages/backend-defaults/src/entrypoints/database/connectors/postgres.ts
index 46b958789d..18418a271a 100644
--- a/packages/backend-defaults/src/entrypoints/database/connectors/postgres.ts
+++ b/packages/backend-defaults/src/entrypoints/database/connectors/postgres.ts
@@ -312,10 +312,6 @@ export class PgConnector implements Connector {
     return client;
   }
 
-  async dropDatabase(...databaseNames: string[]): Promise<void> {
-    return await dropPgDatabase(this.config, ...databaseNames);
-  }
-
   /**
    * Provides the canonical database name for a given plugin.
    *
diff --git a/packages/backend-defaults/src/entrypoints/database/connectors/sqlite3.ts b/packages/backend-defaults/src/entrypoints/database/connectors/sqlite3.ts
index 97ba6d46fd..77e8303390 100644
--- a/packages/backend-defaults/src/entrypoints/database/connectors/sqlite3.ts
+++ b/packages/backend-defaults/src/entrypoints/database/connectors/sqlite3.ts
@@ -210,10 +210,6 @@ export class Sqlite3Connector implements Connector {
     return client;
   }
 
-  async dropDatabase(..._databaseNames: string[]): Promise<void> {
-    // do nothing
-  }
-
   /**
    * Provides the canonical database name for a given plugin.
    *
diff --git a/packages/backend-defaults/src/entrypoints/database/types.ts b/packages/backend-defaults/src/entrypoints/database/types.ts
index 74f41581f6..57b85ff3c1 100644
--- a/packages/backend-defaults/src/entrypoints/database/types.ts
+++ b/packages/backend-defaults/src/entrypoints/database/types.ts
@@ -30,6 +30,4 @@ export interface Connector {
       pluginMetadata: PluginMetadataService;
     },
   ): Promise<Knex>;
-
-  dropDatabase(...databaseNames: string[]): Promise<void>;
 }

From 85f50d43a183a8ef03749908ce3b7c2888e9ec67 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fredrik=20Adel=C3=B6w?= <freben@gmail.com>
Date: Fri, 30 Aug 2024 14:29:52 +0200
Subject: [PATCH 4/5] force the passing of deps to the database manager
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Fredrik Adelöw <freben@gmail.com>
---
 .changeset/wise-forks-play.md                 |  3 +-
 packages/backend-common/api-report.md         |  5 ++-
 .../backend-common/src/deprecated/index.ts    | 29 ++++++++++++--
 .../backend-defaults/api-report-database.md   |  6 +--
 .../database/DatabaseManager.test.ts          | 40 +++++++++++--------
 .../entrypoints/database/DatabaseManager.ts   | 26 +++++++-----
 .../entrypoints/database/connectors/mysql.ts  |  9 ++---
 .../database/connectors/postgres.ts           |  9 ++---
 .../database/connectors/sqlite3.test.ts       | 10 ++++-
 .../database/connectors/sqlite3.ts            | 21 +++++-----
 .../database/databaseServiceFactory.ts        |  5 ++-
 .../src/entrypoints/database/types.ts         |  9 ++---
 12 files changed, 102 insertions(+), 70 deletions(-)

diff --git a/.changeset/wise-forks-play.md b/.changeset/wise-forks-play.md
index 84a6da9003..c5348a8add 100644
--- a/.changeset/wise-forks-play.md
+++ b/.changeset/wise-forks-play.md
@@ -6,5 +6,6 @@
 **BREAKING**: Simplifications and cleanup as part of the Backend System 1.0 work.
 
 - The deprecated `dropDatabase` function has now been removed, without replacement.
-- The deprecated `LegacyRootDatabaseService` type has now been removed. The implication is that you now need to pass deps to a `DatabaseManager` when constructing one.
+- The deprecated `LegacyRootDatabaseService` type has now been removed.
 - The return type from `DatabaseManager.forPlugin` is now directly a `DatabaseService`, as arguably expected.
+- `DatabaseManager.forPlugin` now requires the `deps` argument, with the logger and lifecycle services.
diff --git a/packages/backend-common/api-report.md b/packages/backend-common/api-report.md
index 2555ab6f5b..8a895dd037 100644
--- a/packages/backend-common/api-report.md
+++ b/packages/backend-common/api-report.md
@@ -157,7 +157,10 @@ export class DatabaseManager {
   // (undocumented)
   static fromConfig(
     config: Config,
-    options?: DatabaseManagerOptions,
+    options?: {
+      migrations?: DatabaseService['migrations'];
+      logger?: LoggerService;
+    },
   ): DatabaseManager;
 }
 
diff --git a/packages/backend-common/src/deprecated/index.ts b/packages/backend-common/src/deprecated/index.ts
index d34b81aa92..3b4b518de1 100644
--- a/packages/backend-common/src/deprecated/index.ts
+++ b/packages/backend-common/src/deprecated/index.ts
@@ -46,6 +46,8 @@ import {
   isChildPath as _isChildPath,
   LifecycleService,
   PluginMetadataService,
+  DatabaseService,
+  LoggerService,
 } from '@backstage/backend-plugin-api';
 
 export * from './hot';
@@ -168,14 +170,20 @@ export type CacheClientOptions = CacheServiceOptions;
  * @deprecated Use `DatabaseManager` from the `@backstage/backend-defaults` package instead
  */
 export class DatabaseManager {
-  private constructor(private readonly _databaseManager: _DatabaseManager) {}
+  private constructor(
+    private readonly _databaseManager: _DatabaseManager,
+    private readonly logger?: LoggerService,
+  ) {}
 
   static fromConfig(
     config: Config,
-    options?: DatabaseManagerOptions,
+    options?: {
+      migrations?: DatabaseService['migrations'];
+      logger?: LoggerService;
+    },
   ): DatabaseManager {
     const _databaseManager = _DatabaseManager.fromConfig(config, options);
-    return new DatabaseManager(_databaseManager);
+    return new DatabaseManager(_databaseManager, options?.logger);
   }
 
   forPlugin(
@@ -184,7 +192,20 @@ export class DatabaseManager {
       | { lifecycle: LifecycleService; pluginMetadata: PluginMetadataService }
       | undefined,
   ): PluginDatabaseManager {
-    return this._databaseManager.forPlugin(pluginId, deps);
+    const logger: LoggerService = this.logger ?? {
+      debug() {},
+      info() {},
+      warn() {},
+      error() {},
+      child() {
+        return this;
+      },
+    };
+    const lifecycle: LifecycleService = deps?.lifecycle ?? {
+      addShutdownHook() {},
+      addStartupHook() {},
+    };
+    return this._databaseManager.forPlugin(pluginId, { logger, lifecycle });
   }
 }
 
diff --git a/packages/backend-defaults/api-report-database.md b/packages/backend-defaults/api-report-database.md
index 8f3857fe23..d9e9e9e287 100644
--- a/packages/backend-defaults/api-report-database.md
+++ b/packages/backend-defaults/api-report-database.md
@@ -6,7 +6,6 @@
 import { DatabaseService } from '@backstage/backend-plugin-api';
 import { LifecycleService } from '@backstage/backend-plugin-api';
 import { LoggerService } from '@backstage/backend-plugin-api';
-import { PluginMetadataService } from '@backstage/backend-plugin-api';
 import { RootConfigService } from '@backstage/backend-plugin-api';
 import { ServiceFactory } from '@backstage/backend-plugin-api';
 
@@ -14,9 +13,9 @@ import { ServiceFactory } from '@backstage/backend-plugin-api';
 export class DatabaseManager {
   forPlugin(
     pluginId: string,
-    deps?: {
+    deps: {
+      logger: LoggerService;
       lifecycle: LifecycleService;
-      pluginMetadata: PluginMetadataService;
     },
   ): DatabaseService;
   static fromConfig(
@@ -28,7 +27,6 @@ export class DatabaseManager {
 // @public
 export type DatabaseManagerOptions = {
   migrations?: DatabaseService['migrations'];
-  logger?: LoggerService;
 };
 
 // @public
diff --git a/packages/backend-defaults/src/entrypoints/database/DatabaseManager.test.ts b/packages/backend-defaults/src/entrypoints/database/DatabaseManager.test.ts
index fca6080329..26c2d54231 100644
--- a/packages/backend-defaults/src/entrypoints/database/DatabaseManager.test.ts
+++ b/packages/backend-defaults/src/entrypoints/database/DatabaseManager.test.ts
@@ -17,12 +17,18 @@
 import { ConfigReader } from '@backstage/config';
 import { DatabaseManagerImpl } from './DatabaseManager';
 import { Connector } from './types';
+import { mockServices } from '@backstage/backend-test-utils';
 
 describe('DatabaseManagerImpl', () => {
   afterEach(() => {
     jest.clearAllMocks();
   });
 
+  const deps = {
+    logger: mockServices.logger.mock(),
+    lifecycle: mockServices.lifecycle.mock(),
+  };
+
   it('calls the right connector, only once per plugin id', async () => {
     const connector1 = {
       getClient: jest.fn(),
@@ -41,19 +47,19 @@ describe('DatabaseManagerImpl', () => {
       },
     );
 
-    await impl.forPlugin('plugin1').getClient();
+    await impl.forPlugin('plugin1', deps).getClient();
     expect(connector1.getClient).toHaveBeenCalledTimes(1);
-    expect(connector1.getClient).toHaveBeenLastCalledWith('plugin1', undefined);
+    expect(connector1.getClient).toHaveBeenLastCalledWith('plugin1', deps);
     expect(connector2.getClient).toHaveBeenCalledTimes(0);
 
-    await impl.forPlugin('plugin1').getClient();
+    await impl.forPlugin('plugin1', deps).getClient();
     expect(connector1.getClient).toHaveBeenCalledTimes(1);
-    expect(connector1.getClient).toHaveBeenLastCalledWith('plugin1', undefined);
+    expect(connector1.getClient).toHaveBeenLastCalledWith('plugin1', deps);
     expect(connector2.getClient).toHaveBeenCalledTimes(0);
 
-    await impl.forPlugin('plugin2').getClient();
+    await impl.forPlugin('plugin2', deps).getClient();
     expect(connector1.getClient).toHaveBeenCalledTimes(2);
-    expect(connector1.getClient).toHaveBeenLastCalledWith('plugin2', undefined);
+    expect(connector1.getClient).toHaveBeenLastCalledWith('plugin2', deps);
     expect(connector2.getClient).toHaveBeenCalledTimes(0);
   });
 
@@ -80,16 +86,16 @@ describe('DatabaseManagerImpl', () => {
       },
     );
 
-    await impl.forPlugin('plugin1').getClient();
+    await impl.forPlugin('plugin1', deps).getClient();
     expect(connector1.getClient).toHaveBeenCalledTimes(1);
-    expect(connector1.getClient).toHaveBeenLastCalledWith('plugin1', undefined);
+    expect(connector1.getClient).toHaveBeenLastCalledWith('plugin1', deps);
     expect(connector2.getClient).toHaveBeenCalledTimes(0);
 
-    await impl.forPlugin('plugin2').getClient();
+    await impl.forPlugin('plugin2', deps).getClient();
     expect(connector1.getClient).toHaveBeenCalledTimes(1);
-    expect(connector1.getClient).toHaveBeenLastCalledWith('plugin1', undefined);
+    expect(connector1.getClient).toHaveBeenLastCalledWith('plugin1', deps);
     expect(connector2.getClient).toHaveBeenCalledTimes(1);
-    expect(connector2.getClient).toHaveBeenLastCalledWith('plugin2', undefined);
+    expect(connector2.getClient).toHaveBeenLastCalledWith('plugin2', deps);
   });
 
   it('migration skip options take precedence over config', async () => {
@@ -112,7 +118,7 @@ describe('DatabaseManagerImpl', () => {
       },
       { migrations: { skip: false } },
     );
-    expect((await impl.forPlugin('plugin1')).migrations).toEqual({
+    expect((await impl.forPlugin('plugin1', deps)).migrations).toEqual({
       skip: false,
     });
 
@@ -120,7 +126,7 @@ describe('DatabaseManagerImpl', () => {
       pg: connector,
     });
 
-    expect((await impl1.forPlugin('plugin1')).migrations).toEqual({
+    expect((await impl1.forPlugin('plugin1', deps)).migrations).toEqual({
       skip: false,
     });
   });
@@ -142,10 +148,10 @@ describe('DatabaseManagerImpl', () => {
       },
     );
 
-    expect((await impl.forPlugin('plugin1')).migrations).toEqual({
+    expect((await impl.forPlugin('plugin1', deps)).migrations).toEqual({
       skip: true,
     });
-    expect((await impl.forPlugin('plugin2')).migrations).toEqual({
+    expect((await impl.forPlugin('plugin2', deps)).migrations).toEqual({
       skip: false,
     });
 
@@ -163,10 +169,10 @@ describe('DatabaseManagerImpl', () => {
         pg: connector,
       },
     );
-    expect((await impl2.forPlugin('plugin1')).migrations).toEqual({
+    expect((await impl2.forPlugin('plugin1', deps)).migrations).toEqual({
       skip: false,
     });
-    expect((await impl2.forPlugin('plugin2')).migrations).toEqual({
+    expect((await impl2.forPlugin('plugin2', deps)).migrations).toEqual({
       skip: true,
     });
   });
diff --git a/packages/backend-defaults/src/entrypoints/database/DatabaseManager.ts b/packages/backend-defaults/src/entrypoints/database/DatabaseManager.ts
index 1230280e07..46d4ee8cf7 100644
--- a/packages/backend-defaults/src/entrypoints/database/DatabaseManager.ts
+++ b/packages/backend-defaults/src/entrypoints/database/DatabaseManager.ts
@@ -18,7 +18,6 @@ import {
   DatabaseService,
   LifecycleService,
   LoggerService,
-  PluginMetadataService,
   RootConfigService,
 } from '@backstage/backend-plugin-api';
 import { Config } from '@backstage/config';
@@ -43,7 +42,6 @@ function pluginPath(pluginId: string): string {
  */
 export type DatabaseManagerOptions = {
   migrations?: DatabaseService['migrations'];
-  logger?: LoggerService;
 };
 
 /**
@@ -66,9 +64,9 @@ export class DatabaseManagerImpl {
    */
   forPlugin(
     pluginId: string,
-    deps?: {
+    deps: {
+      logger: LoggerService;
       lifecycle: LifecycleService;
-      pluginMetadata: PluginMetadataService;
     },
   ): PluginDatabaseManager {
     const client = this.getClientType(pluginId).client;
@@ -128,9 +126,9 @@ export class DatabaseManagerImpl {
   private async getDatabase(
     pluginId: string,
     connector: Connector,
-    deps?: {
+    deps: {
+      logger: LoggerService;
       lifecycle: LifecycleService;
-      pluginMetadata: PluginMetadataService;
     },
   ): Promise<Knex> {
     if (this.databaseCache.has(pluginId)) {
@@ -141,13 +139,19 @@ export class DatabaseManagerImpl {
     this.databaseCache.set(pluginId, clientPromise);
 
     if (process.env.NODE_ENV !== 'test') {
-      clientPromise.then(client => this.startKeepaliveLoop(pluginId, client));
+      clientPromise.then(client =>
+        this.startKeepaliveLoop(pluginId, client, deps.logger),
+      );
     }
 
     return clientPromise;
   }
 
-  private startKeepaliveLoop(pluginId: string, client: Knex): void {
+  private startKeepaliveLoop(
+    pluginId: string,
+    client: Knex,
+    logger: LoggerService,
+  ): void {
     let lastKeepaliveFailed = false;
 
     setInterval(() => {
@@ -160,7 +164,7 @@ export class DatabaseManagerImpl {
         (error: unknown) => {
           if (!lastKeepaliveFailed) {
             lastKeepaliveFailed = true;
-            this.options?.logger?.warn(
+            logger.warn(
               `Database keepalive failed for plugin ${pluginId}, ${stringifyError(
                 error,
               )}`,
@@ -225,9 +229,9 @@ export class DatabaseManager {
    */
   forPlugin(
     pluginId: string,
-    deps?: {
+    deps: {
+      logger: LoggerService;
       lifecycle: LifecycleService;
-      pluginMetadata: PluginMetadataService;
     },
   ): PluginDatabaseManager {
     return this.impl.forPlugin(pluginId, deps);
diff --git a/packages/backend-defaults/src/entrypoints/database/connectors/mysql.ts b/packages/backend-defaults/src/entrypoints/database/connectors/mysql.ts
index f06db5999d..d5bd88deef 100644
--- a/packages/backend-defaults/src/entrypoints/database/connectors/mysql.ts
+++ b/packages/backend-defaults/src/entrypoints/database/connectors/mysql.ts
@@ -14,10 +14,7 @@
  * limitations under the License.
  */
 
-import {
-  LifecycleService,
-  PluginMetadataService,
-} from '@backstage/backend-plugin-api';
+import { LifecycleService, LoggerService } from '@backstage/backend-plugin-api';
 import { Config, ConfigReader } from '@backstage/config';
 import { InputError } from '@backstage/errors';
 import { JsonObject } from '@backstage/types';
@@ -253,9 +250,9 @@ export class MysqlConnector implements Connector {
 
   async getClient(
     pluginId: string,
-    _deps?: {
+    _deps: {
+      logger: LoggerService;
       lifecycle: LifecycleService;
-      pluginMetadata: PluginMetadataService;
     },
   ): Promise<Knex> {
     const pluginConfig = new ConfigReader(
diff --git a/packages/backend-defaults/src/entrypoints/database/connectors/postgres.ts b/packages/backend-defaults/src/entrypoints/database/connectors/postgres.ts
index 18418a271a..b5cfffd1f4 100644
--- a/packages/backend-defaults/src/entrypoints/database/connectors/postgres.ts
+++ b/packages/backend-defaults/src/entrypoints/database/connectors/postgres.ts
@@ -14,10 +14,7 @@
  * limitations under the License.
  */
 
-import {
-  LifecycleService,
-  PluginMetadataService,
-} from '@backstage/backend-plugin-api';
+import { LifecycleService, LoggerService } from '@backstage/backend-plugin-api';
 import { Config, ConfigReader } from '@backstage/config';
 import { ForwardedError } from '@backstage/errors';
 import { JsonObject } from '@backstage/types';
@@ -261,9 +258,9 @@ export class PgConnector implements Connector {
 
   async getClient(
     pluginId: string,
-    _deps?: {
+    _deps: {
+      logger: LoggerService;
       lifecycle: LifecycleService;
-      pluginMetadata: PluginMetadataService;
     },
   ): Promise<Knex> {
     const pluginConfig = new ConfigReader(
diff --git a/packages/backend-defaults/src/entrypoints/database/connectors/sqlite3.test.ts b/packages/backend-defaults/src/entrypoints/database/connectors/sqlite3.test.ts
index 2bd517d373..769d402eda 100644
--- a/packages/backend-defaults/src/entrypoints/database/connectors/sqlite3.test.ts
+++ b/packages/backend-defaults/src/entrypoints/database/connectors/sqlite3.test.ts
@@ -20,11 +20,17 @@ import {
   buildSqliteDatabaseConfig,
   createSqliteDatabaseClient,
 } from './sqlite3';
+import { mockServices } from '@backstage/backend-test-utils';
 
 describe('better-sqlite3', () => {
   const createConfig = (connection: any) =>
     new ConfigReader({ client: 'better-sqlite3', connection });
 
+  const deps = {
+    logger: mockServices.logger.mock(),
+    lifecycle: mockServices.lifecycle.mock(),
+  };
+
   describe('buildSqliteDatabaseConfig', () => {
     it('builds an in-memory connection', () => {
       expect(buildSqliteDatabaseConfig(createConfig(':memory:'))).toEqual({
@@ -90,7 +96,9 @@ describe('better-sqlite3', () => {
 
   describe('createSqliteDatabaseClient', () => {
     it('creates an in memory knex instance', () => {
-      expect(createSqliteDatabaseClient(createConfig(':memory:'))).toBeTruthy();
+      expect(
+        createSqliteDatabaseClient('p', createConfig(':memory:'), deps),
+      ).toBeTruthy();
     });
   });
 });
diff --git a/packages/backend-defaults/src/entrypoints/database/connectors/sqlite3.ts b/packages/backend-defaults/src/entrypoints/database/connectors/sqlite3.ts
index 77e8303390..67dd9d975f 100644
--- a/packages/backend-defaults/src/entrypoints/database/connectors/sqlite3.ts
+++ b/packages/backend-defaults/src/entrypoints/database/connectors/sqlite3.ts
@@ -15,10 +15,7 @@
  */
 
 import { DevDataStore } from '@backstage/backend-dev-utils';
-import {
-  LifecycleService,
-  PluginMetadataService,
-} from '@backstage/backend-plugin-api';
+import { LifecycleService, LoggerService } from '@backstage/backend-plugin-api';
 import { Config, ConfigReader } from '@backstage/config';
 import { JsonObject } from '@backstage/types';
 import { ensureDirSync } from 'fs-extra';
@@ -35,12 +32,13 @@ import { mergeDatabaseConfig } from './mergeDatabaseConfig';
  * @param overrides - Additional options to merge with the config
  */
 export function createSqliteDatabaseClient(
+  pluginId: string,
   dbConfig: Config,
-  overrides?: Knex.Config,
-  deps?: {
+  deps: {
+    logger: LoggerService;
     lifecycle: LifecycleService;
-    pluginMetadata: PluginMetadataService;
   },
+  overrides?: Knex.Config,
 ) {
   const knexConfig = buildSqliteDatabaseConfig(dbConfig, overrides);
   const connConfig = knexConfig.connection as Knex.Sqlite3ConnectionConfig;
@@ -62,7 +60,7 @@ export function createSqliteDatabaseClient(
     const devStore = DevDataStore.get();
 
     if (devStore) {
-      const dataKey = `sqlite3-db-${deps.pluginMetadata.getId()}`;
+      const dataKey = `sqlite3-db-${pluginId}`;
 
       const connectionLoader = async () => {
         // If seed data is available, use it tconnectionLoader restore the database
@@ -180,9 +178,9 @@ export class Sqlite3Connector implements Connector {
 
   async getClient(
     pluginId: string,
-    deps?: {
+    deps: {
+      logger: LoggerService;
       lifecycle: LifecycleService;
-      pluginMetadata: PluginMetadataService;
     },
   ): Promise<Knex> {
     const pluginConfig = new ConfigReader(
@@ -202,9 +200,10 @@ export class Sqlite3Connector implements Connector {
     );
 
     const client = createSqliteDatabaseClient(
+      pluginId,
       pluginConfig,
-      databaseClientOverrides,
       deps,
+      databaseClientOverrides,
     );
 
     return client;
diff --git a/packages/backend-defaults/src/entrypoints/database/databaseServiceFactory.ts b/packages/backend-defaults/src/entrypoints/database/databaseServiceFactory.ts
index 3bdf1790f3..167779e807 100644
--- a/packages/backend-defaults/src/entrypoints/database/databaseServiceFactory.ts
+++ b/packages/backend-defaults/src/entrypoints/database/databaseServiceFactory.ts
@@ -35,6 +35,7 @@ export const databaseServiceFactory = createServiceFactory({
   deps: {
     config: coreServices.rootConfig,
     lifecycle: coreServices.lifecycle,
+    logger: coreServices.logger,
     pluginMetadata: coreServices.pluginMetadata,
   },
   async createRootContext({ config }) {
@@ -48,10 +49,10 @@ export const databaseServiceFactory = createServiceFactory({
           }),
         );
   },
-  async factory({ pluginMetadata, lifecycle }, databaseManager) {
+  async factory({ pluginMetadata, lifecycle, logger }, databaseManager) {
     return databaseManager.forPlugin(pluginMetadata.getId(), {
-      pluginMetadata,
       lifecycle,
+      logger,
     });
   },
 });
diff --git a/packages/backend-defaults/src/entrypoints/database/types.ts b/packages/backend-defaults/src/entrypoints/database/types.ts
index 57b85ff3c1..beded85d65 100644
--- a/packages/backend-defaults/src/entrypoints/database/types.ts
+++ b/packages/backend-defaults/src/entrypoints/database/types.ts
@@ -14,10 +14,7 @@
  * limitations under the License.
  */
 
-import {
-  LifecycleService,
-  PluginMetadataService,
-} from '@backstage/backend-plugin-api';
+import { LifecycleService, LoggerService } from '@backstage/backend-plugin-api';
 import { Knex } from 'knex';
 
 export type { DatabaseService as PluginDatabaseManager } from '@backstage/backend-plugin-api';
@@ -25,9 +22,9 @@ export type { DatabaseService as PluginDatabaseManager } from '@backstage/backen
 export interface Connector {
   getClient(
     pluginId: string,
-    deps?: {
+    deps: {
+      logger: LoggerService;
       lifecycle: LifecycleService;
-      pluginMetadata: PluginMetadataService;
     },
   ): Promise<Knex>;
 }

From 988c1454bdb3c414eaebc9c593c396daafa2b191 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fredrik=20Adel=C3=B6w?= <freben@gmail.com>
Date: Fri, 30 Aug 2024 15:16:12 +0200
Subject: [PATCH 5/5] put back the types in common
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Fredrik Adelöw <freben@gmail.com>
---
 .changeset/chilly-birds-shout.md                |  7 +++++++
 .changeset/wise-forks-play.md                   |  1 -
 packages/backend-common/api-report.md           |  7 ++++++-
 packages/backend-common/src/deprecated/index.ts | 10 +++++++++-
 4 files changed, 22 insertions(+), 3 deletions(-)
 create mode 100644 .changeset/chilly-birds-shout.md

diff --git a/.changeset/chilly-birds-shout.md b/.changeset/chilly-birds-shout.md
new file mode 100644
index 0000000000..dfa99b6f5d
--- /dev/null
+++ b/.changeset/chilly-birds-shout.md
@@ -0,0 +1,7 @@
+---
+'@backstage/backend-common': minor
+---
+
+**BREAKING**: Simplifications and cleanup as part of the Backend System 1.0 work.
+
+- The deprecated `dropDatabase` function has now been removed, without replacement.
diff --git a/.changeset/wise-forks-play.md b/.changeset/wise-forks-play.md
index c5348a8add..3846b3a6f0 100644
--- a/.changeset/wise-forks-play.md
+++ b/.changeset/wise-forks-play.md
@@ -1,5 +1,4 @@
 ---
-'@backstage/backend-common': minor
 '@backstage/backend-defaults': minor
 ---
 
diff --git a/packages/backend-common/api-report.md b/packages/backend-common/api-report.md
index 8a895dd037..450bee9063 100644
--- a/packages/backend-common/api-report.md
+++ b/packages/backend-common/api-report.md
@@ -143,7 +143,7 @@ export function createStatusCheckRouter(options: {
 }): Promise<express.Router>;
 
 // @public @deprecated (undocumented)
-export class DatabaseManager {
+export class DatabaseManager implements LegacyRootDatabaseService {
   // (undocumented)
   forPlugin(
     pluginId: string,
@@ -365,6 +365,11 @@ export const legacyPlugin: (
   }>,
 ) => BackendFeature;
 
+// @public @deprecated (undocumented)
+export type LegacyRootDatabaseService = {
+  forPlugin(pluginId: string): DatabaseService;
+};
+
 // @public @deprecated
 export function loadBackendConfig(options: {
   logger: LoggerService;
diff --git a/packages/backend-common/src/deprecated/index.ts b/packages/backend-common/src/deprecated/index.ts
index 3b4b518de1..7f18bd188e 100644
--- a/packages/backend-common/src/deprecated/index.ts
+++ b/packages/backend-common/src/deprecated/index.ts
@@ -169,7 +169,7 @@ export type CacheClientOptions = CacheServiceOptions;
  * @public
  * @deprecated Use `DatabaseManager` from the `@backstage/backend-defaults` package instead
  */
-export class DatabaseManager {
+export class DatabaseManager implements LegacyRootDatabaseService {
   private constructor(
     private readonly _databaseManager: _DatabaseManager,
     private readonly logger?: LoggerService,
@@ -221,6 +221,14 @@ export type DatabaseManagerOptions = _DatabaseManagerOptions;
  */
 export type PluginDatabaseManager = _PluginDatabaseManager;
 
+/**
+ * @public
+ * @deprecated Use `DatabaseManager` from `@backstage/backend-defaults/database` instead, or migrate to the new backend system and use `coreServices.database`
+ */
+export type LegacyRootDatabaseService = {
+  forPlugin(pluginId: string): DatabaseService;
+};
+
 /**
  * @public
  * @deprecated This function is deprecated and will be removed in a future release, see https://github.com/backstage/backstage/issues/24493.