Merge pull request #2674 from lowjoel/postgres-create-database

Auto-create plugin databases

packages/backend-common/src/database/connection.ts

@@ -17,7 +17,7 @@
 import knex from 'knex';
 import { Config } from '@backstage/config';
 import { mergeDatabaseConfig } from './config';
-import { createPgDatabaseClient } from './postgres';
+import { createPgDatabaseClient, ensurePgDatabaseExists } from './postgres';
 import { createSqliteDatabaseClient } from './sqlite3';
 
 type DatabaseClient = 'pg' | 'sqlite3' | string;
@@ -48,3 +48,19 @@ export function createDatabaseClient(
  * @deprecated Use createDatabaseClient instead
  */
 export const createDatabase = createDatabaseClient;
+
+/**
+ * Ensures that the given databases all exist, creating them if they do not.
+ */
+export async function ensureDatabaseExists(
+  dbConfig: Config,
+  ...databases: Array<string>
+) {
+  const client: DatabaseClient = dbConfig.getString('client');
+
+  if (client === 'pg') {
+    return ensurePgDatabaseExists(dbConfig, ...databases);
+  }
+
+  return undefined;
+}

packages/backend-common/src/database/postgres.ts

@@ -95,3 +95,39 @@ function requirePgConnectionString() {
     throw new Error(`${message}\n${e.message}`);
   }
 }
+
+/**
+ * Creates the missing Postgres database if it does not exist
+ *
+ * @param dbConfig The database config
+ * @param databases The name of the databases to create
+ */
+export async function ensurePgDatabaseExists(
+  dbConfig: Config,
+  ...databases: Array<string>
+) {
+  const admin = createPgDatabaseClient(dbConfig, {
+    connection: {
+      database: 'postgres',
+    },
+  });
+
+  try {
+    const ensureDatabase = async (database: string) => {
+      const result = await admin
+        .from('pg_database')
+        .where('datname', database)
+        .count<Record<string, { count: string }>>();
+
+      if (parseInt(result[0].count, 10) > 0) {
+        return;
+      }
+
+      await admin.raw(`CREATE DATABASE ??`, [database]);
+    };
+
+    await Promise.all(databases.map(ensureDatabase));
+  } finally {
+    await admin.destroy();
+  }
+}

packages/backend/src/index.ts

@@ -24,6 +24,7 @@
 
 import Router from 'express-promise-router';
 import {
+  ensureDatabaseExists,
   createDatabaseClient,
   createServiceBuilder,
   loadBackendConfig,
@@ -68,6 +69,12 @@ async function main() {
   const configs = await loadBackendConfig();
   const configReader = ConfigReader.fromConfigs(configs);
   const createEnv = makeCreateEnv(configs);
+  await ensureDatabaseExists(
+    configReader.getConfig('backend.database'),
+    'backstage_plugin_catalog',
+    'backstage_plugin_auth',
+  );
+
   const healthcheckEnv = useHotMemoize(module, () => createEnv('healthcheck'));
   const catalogEnv = useHotMemoize(module, () => createEnv('catalog'));
   const scaffolderEnv = useHotMemoize(module, () => createEnv('scaffolder'));

packages/create-app/templates/default-app/packages/backend/src/index.ts

@@ -8,6 +8,7 @@
 
 import Router from 'express-promise-router';
 import {
+  ensureDatabaseExists,
   createDatabaseClient,
   createServiceBuilder,
   loadBackendConfig,
@@ -46,6 +47,11 @@ async function main() {
   const configs = await loadBackendConfig();
   const configReader = ConfigReader.fromConfigs(configs);
   const createEnv = makeCreateEnv(configs);
+  await ensureDatabaseExists(
+    configReader.getConfig('backend.database'),
+    'backstage_plugin_catalog',
+    'backstage_plugin_auth',
+  );
 
   const catalogEnv = useHotMemoize(module, () => createEnv('catalog'));
   const scaffolderEnv = useHotMemoize(module, () => createEnv('scaffolder'));