respect ensureExists when pluginDivisionMode is set to schema.

Signed-off-by: Andrew Duckett <andrew.duckett@gmail.com>

.changeset/purple-apricots-build.md

@@ -0,0 +1,5 @@
+---
+'@backstage/backend-common': patch
+---
+
+**BREAKING** The config prop `ensureExists` now applies to schema creation when `pluginDivisionMode` is set to `schema`. This means schemas will no longer be automatically created when `ensureExists` is set to `false`. In this case the `pg` database as well as each `schema` must be created out of band.

packages/backend-common/src/database/DatabaseManager.test.ts

@@ -612,6 +612,31 @@ describe('DatabaseManager', () => {
       );
     });
 
+    it('ensureExists does not create database or schema when false', async () => {
+      const testManager = DatabaseManager.fromConfig(
+        new ConfigReader({
+          backend: {
+            database: {
+              client: 'pg',
+              pluginDivisionMode: 'schema',
+              ensureExists: false,
+              connection: {
+                host: 'localhost',
+                user: 'foo',
+                password: 'bar',
+                database: 'foodb',
+              },
+            },
+          },
+        }),
+      );
+      const pluginId = 'testdbname';
+      await testManager.forPlugin(pluginId).getClient();
+
+      expect(mocked(ensureDatabaseExists)).toHaveBeenCalledTimes(0);
+      expect(mocked(ensureSchemaExists)).toHaveBeenCalledTimes(0);
+    });
+
     it('fetches and merges additional knex config', async () => {
       const testManager = DatabaseManager.fromConfig(
         new ConfigReader({

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

@@ -321,13 +321,15 @@ export class DatabaseManager {
 
     let schemaOverrides;
     if (this.getPluginDivisionModeConfig() === 'schema') {
-      try {
-        schemaOverrides = this.getSchemaOverrides(pluginId);
-        await ensureSchemaExists(pluginConfig, pluginId);
-      } catch (error) {
-        throw new Error(
-          `Failed to connect to the database to make sure that schema for plugin '${pluginId}' exists, ${error}`,
-        );
+      schemaOverrides = this.getSchemaOverrides(pluginId);
+      if (this.getEnsureExistsConfig(pluginId)) {
+        try {
+          await ensureSchemaExists(pluginConfig, pluginId);
+        } catch (error) {
+          throw new Error(
+            `Failed to connect to the database to make sure that schema for plugin '${pluginId}' exists, ${error}`,
+          );
+        }
       }
     }