Migrate off of legacy bundled services

Most of the functionality provided by the legacy bundled services is now provided by the Cloud Client Libraries. For more information, see the recommended alternatives listed below.

If migrating to an unbundled solution is not an option for your project, then you may be able to continue using legacy bundled services in your apps as a fallback. This approach gives you flexibility to move to unbundled services later in the migration cycle.

Migration paths for App Engine bundled services


To store and retrieve data, use Cloud Storage through the Cloud Client Libraries. To get started, see Using Cloud Storage.



You can serve images from Cloud Storage, serve them directly, or use a third-party content delivery network (CDN).

The App Engine Images service also provided functionality to avoid dynamic requests to your application by handling image resizing using a serving URL. If you want similar functionality, you can generate the re-sized images ahead of time and upload them to Cloud Storage for serving. Alternatively, you could use a third-party content delivery network (CDN) service that offers image resizing.


We recommend that you update your app to use Cloud Logging, which supports features such as viewing logs in the Logs Explorer, downloading logs, filtering messages by severity, and correlating app messages with specific requests. Alternatively, if you prefer simplicity over data accuracy, you can write structured logs to stdout or stderr. For more information, see Writing and viewing logs.


To send email, use a third-party mail provider such as SendGrid, Mailgun, or Mailjet. All of these services offer APIs to send emails from applications. A recommended third-party alternative for inbound messaging is not available at this time.


To cache application data, use Memorystore for Redis.


To obtain information and modify your application's running services, use a combination of environment variables and the App Engine Admin API:

Service information How to access
Current application ID GAE_APPLICATION environment variable
Current project ID GOOGLE_CLOUD_PROJECT environment variable
Current service name GAE_SERVICE environment variable
Current service version GAE_VERSION environment variable
Current instance ID GAE_INSTANCE environment variable
Default hostname Admin API apps.get method
List of services Admin API apps.services.list method
List of versions for a service Admin API apps.services.versions.list method
Default version for a service, including any traffic splits Admin API apps.services.get method
List of running instances for a version Admin API apps.services.versions.instances.list method

For more information about the data available about your application's running services, see runtime environment.


Instead of using the App Engine OAuth service to verify OAuth 2.0 tokens, use the oauth2.tokeninfo method of the OAuth 2.0 API.

Host any full-text search database such as Elasticsearch on Compute Engine and access it from your service.

Task queue

Queue tasks for asynchronous code execution using the Cloud Tasks REST API, RPC API, or the Cloud Client Libraries, and use a App Engine standard service as a Push target. For more information, see Migrating from Task Queues to Cloud Tasks.

In many cases where you might use pull queues, such as queuing up tasks or messages that will be pulled and processed by separate workers, Pub/Sub can be a good alternative as it offers similar functionality and delivery guarantees.

User authentication

For an alternative to the Users API, use any of the HTTP-based authentication mechanisms described on the User authentication page.