App Engine HTTP request.
The message defines the HTTP request that is sent to an App Engine app when the task is dispatched.
Using AppEngineHttpRequest
requires
`appengine.applications.get https://cloud.google.com/appengine/docs/admin-api/access-control`_
Google IAM permission for the project and the following scope:
https://www.googleapis.com/auth/cloud-platform
The task will be delivered to the App Engine app which belongs to the
same project as the queue. For more information, see How Requests are
Routed <https://cloud.google.com/appengine/docs/standard/python/how-requests-are-routed>
and how routing is affected by dispatch
files <https://cloud.google.com/appengine/docs/python/config/dispatchref>.
Traffic is encrypted during transport and never leaves Google
datacenters. Because this traffic is carried over a communication
mechanism internal to Google, you cannot explicitly set the protocol
(for example, HTTP or HTTPS). The request to the handler, however, will
appear to have used the HTTP protocol.
The AppEngineRouting used to construct the URL that the task is delivered to can be set at the queue-level or task-level:
- If [app_engine_routing_override is set on the queue][Queue.app_engine_routing_override], this value is used for all tasks in the queue, no matter what the setting is for the [task-level app_engine_routing][AppEngineHttpRequest.app_engine_routing].
The url that the task will be sent to is:
url =host+[relative_uri][google.cloud.tasks.v2.AppEngineHttpRequest.relative_uri]
Tasks can be dispatched to secure app handlers, unsecure app handlers,
and URIs restricted with
login: admin`` <https://cloud.google.com/appengine/docs/standard/python/config/appref>`_.
Because tasks are not run as any user, they cannot be dispatched to URIs
restricted withlogin: required` <https://cloud.google.com/appengine/docs/standard/python/config/appref>_
Task dispatches also do not follow redirects.
The task attempt has succeeded if the app's request handler returns an
HTTP response code in the range [200 - 299]. The task attempt
has failed if the app's handler returns a non-2xx response code or Cloud
Tasks does not receive response before the
[deadline][google.cloud.tasks.v2.Task.dispatch_deadline]. Failed tasks
will be retried according to the [retry
configuration][google.cloud.tasks.v2.Queue.retry_config]. 503
(Service Unavailable) is considered an App Engine system error instead
of an application error and will cause Cloud Tasks' traffic congestion
control to temporarily throttle the queue's dispatches. Unlike other
types of task targets, a 429 (Too Many Requests) response from an
app handler does not cause traffic congestion control to throttle the
queue.
Task-level setting for App Engine routing. - If [app_engine_routing_override is set on the queue][Queue.app_engine_routing_override], this value is used for all tasks in the queue, no matter what the setting is for the [task-level app_engine_routing][AppEngineHt tpRequest.app_engine_routing].
HTTP request headers. This map contains the header field
names and values. Headers can be set when the [task is
created][google.cloud.tasks.v2.CloudTasks.CreateTask].
Repeated headers are not supported but a header value can
contain commas. Cloud Tasks sets some headers to default
values: - User-Agent: By default, this header is
"AppEngine-Google; (+http://code.google.com/appengine)".
This header can be modified, but Cloud Tasks will append
"AppEngine-Google; (+http://code.google.com/appengine)" to
the modified User-Agent. If the task has a
body, Cloud
Tasks sets the following headers: - Content-Type: By
default, the Content-Type header is set to
"application/octet-stream". The default can be overridden
by explicitly setting Content-Type to a particular
media type when the [task is
created][google.cloud.tasks.v2.CloudTasks.CreateTask]. For
example, Content-Type can be set to
"application/json". - Content-Length: This is
computed by Cloud Tasks. This value is output only. It
cannot be changed. The headers below cannot be set or
overridden: - Host - X-Google-* -
X-AppEngine-* In addition, Cloud Tasks sets some headers
when the task is dispatched, such as headers containing
information about the task; see request headers
<https://cloud.google.com/tasks/docs/creating-appengine-
handlers#reading_request_headers>_. These headers are set
only when the task is dispatched, so they are not visible when
the task is returned in a Cloud Tasks response. Although
there is no specific limit for the maximum number of headers
or the size, there is a limit on the maximum size of the
Task. For more information, see
the CreateTask
documentation.
Classes
HeadersEntry
API documentation for tasks_v2.types.AppEngineHttpRequest.HeadersEntry class.