test: fix flake system tests (#2217)

* chore: flaky test cases

* moved instance config inside instanconfig describe block

Author: surbhigarg92

system-test/spanner.ts

@@ -215,23 +215,6 @@ describe('Spanner', () => {
         await pg_database.updateSchema(schema);
       await postgreSqlOperationUpdateDDL.promise();
       RESOURCES_TO_CLEAN.push(PG_DATABASE);
-
-      // Create a user-managed instance config from a base instance config.
-      const [baseInstanceConfig] = await spanner.getInstanceConfig(
-        INSTANCE_CONFIG.config
-      );
-      const customInstanceConfigRequest = {
-        replicas: baseInstanceConfig.replicas!.concat(
-          baseInstanceConfig!.optionalReplicas![0]
-        ),
-        baseConfig: baseInstanceConfig.name,
-        gaxOptions: GAX_OPTIONS,
-      };
-      const [, operation] = await instanceConfig.create(
-        customInstanceConfigRequest
-      );
-      await operation.promise();
-      INSTANCE_CONFIGS_TO_CLEAN.push(instanceConfig);
     }
   });
 
@@ -272,15 +255,6 @@ describe('Spanner', () => {
     } catch (err) {
       console.error('Cleanup failed:', err);
     }
-    /**
-     * Deleting instance configs created during this test.
-     * @see {@link https://cloud.google.com/spanner/docs/reference/rpc/google.spanner.admin.instance.v1#google.spanner.admin.instance.v1.InstanceAdmin.DeleteInstanceConfig}
-     */
-    await Promise.all(
-      INSTANCE_CONFIGS_TO_CLEAN.map(instanceConfig =>
-        instanceConfig.delete({gaxOpts: GAX_OPTIONS})
-      )
-    );
   });
 
   describe('Autogenerated Admin Client', async () => {
@@ -2187,6 +2161,39 @@ describe('Spanner', () => {
   });
 
   describe('instanceConfigs', () => {
+    before(async () => {
+      if (!IS_EMULATOR_ENABLED) {
+        // Create a user-managed instance config from a base instance config.
+        const [baseInstanceConfig] = await spanner.getInstanceConfig(
+          INSTANCE_CONFIG.config
+        );
+        const customInstanceConfigRequest = {
+          replicas: baseInstanceConfig.replicas!.concat(
+            baseInstanceConfig!.optionalReplicas![0]
+          ),
+          baseConfig: baseInstanceConfig.name,
+          gaxOptions: GAX_OPTIONS,
+        };
+        const [, operation] = await instanceConfig.create(
+          customInstanceConfigRequest
+        );
+        await operation.promise();
+        INSTANCE_CONFIGS_TO_CLEAN.push(instanceConfig);
+      }
+    });
+
+    after(async () => {
+      /**
+       * Deleting instance configs created during this test.
+       * @see {@link https://cloud.google.com/spanner/docs/reference/rpc/google.spanner.admin.instance.v1#google.spanner.admin.instance.v1.InstanceAdmin.DeleteInstanceConfig}
+       */
+      await Promise.all(
+        INSTANCE_CONFIGS_TO_CLEAN.map(instanceConfig =>
+          instanceConfig.delete({gaxOpts: GAX_OPTIONS})
+        )
+      );
+    });
+
     it('should have created the instance config', function (done) {
       if (IS_EMULATOR_ENABLED) {
         this.skip();
@@ -3952,13 +3959,13 @@ describe('Spanner', () => {
       const [sessions] = await dbNewRole.batchCreateSessions({count});
 
       assert.strictEqual(sessions.length, count);
-      sessions.forEach(session =>
-        session.getMetadata((err, metadata) => {
-          assert.ifError(err);
-          assert.strictEqual('parent_role', metadata?.databaseRole);
+      await Promise.all(
+        sessions.map(async session => {
+          const metadata = await session.getMetadata();
+          assert.strictEqual('parent_role', metadata[0].databaseRole);
+          await session.delete();
         })
       );
-      await Promise.all(sessions.map(session => session.delete()));
     });
 
     it('should batch create sessions with database role by overriding session database-role', async function () {
@@ -3972,13 +3979,13 @@ describe('Spanner', () => {
       });
 
       assert.strictEqual(sessions.length, count);
-      sessions.forEach(session =>
-        session.getMetadata((err, metadata) => {
-          assert.ifError(err);
-          assert.strictEqual('child_role', metadata?.databaseRole);
+      await Promise.all(
+        sessions.map(async session => {
+          const metadata = await session.getMetadata();
+          assert.strictEqual('child_role', metadata[0].databaseRole);
+          await session.delete();
         })
       );
-      await Promise.all(sessions.map(session => session.delete()));
     });
 
     it('should batch create sessions with database role by overriding database-role', async function () {
@@ -3992,13 +3999,13 @@ describe('Spanner', () => {
       });
 
       assert.strictEqual(sessions.length, count);
-      sessions.forEach(session =>
-        session.getMetadata((err, metadata) => {
-          assert.ifError(err);
-          assert.strictEqual('orphan_role', metadata?.databaseRole);
+      await Promise.all(
+        sessions.map(async session => {
+          const metadata = await session.getMetadata();
+          assert.strictEqual('orphan_role', metadata[0].databaseRole);
+          await session.delete();
         })
       );
-      await Promise.all(sessions.map(session => session.delete()));
     });
   });