AppEngineRouting

App Engine Routing.

Defines routing characteristics specific to App Engine - service, version, and instance.

For more information about services, versions, and instances see An Overview of App Engine, Microservices Architecture on Google App Engine, App Engine Standard request routing, and App Engine Flex request routing.

Using AppEngineRouting requires appengine.applications.get Google IAM permission for the project and the following scope:

https://www.googleapis.com/auth/cloud-platform

JSON representation 
{
  "service": string,
  "version": string,
  "instance": string,
  "host": string
}
Fields
service

string

App service.

By default, the task is sent to the service which is the default service when the task is attempted.

For some queues or tasks which were created using the App Engine Task Queue API, host is not parsable into service, version, and instance. For example, some tasks which were created using the App Engine SDK use a custom domain name; custom domains are not parsed by Cloud Tasks. If host is not parsable, then service, version, and instance are the empty string.
version

string

App version.

By default, the task is sent to the version which is the default version when the task is attempted.

For some queues or tasks which were created using the App Engine Task Queue API, host is not parsable into service, version, and instance. For example, some tasks which were created using the App Engine SDK use a custom domain name; custom domains are not parsed by Cloud Tasks. If host is not parsable, then service, version, and instance are the empty string.
instance

string

App instance.

By default, the task is sent to an instance which is available when the task is attempted.

Requests can only be sent to a specific instance if manual scaling is used in App Engine Standard. App Engine Flex does not support instances. For more information, see App Engine Standard request routing and App Engine Flex request routing.
host

string

Output only. The host that the task is sent to.

The host is constructed from the domain name of the app associated with the queue's project ID (for example .appspot.com), and the service, version, and instance. Tasks which were created using the App Engine SDK might have a custom domain name.

For more information, see How Requests are Routed.