Region ID
The REGION_ID is an abbreviated code that Google assigns
based on the region you select when you create your app. The code does not
correspond to a country or province, even though some region IDs may appear
similar to commonly used country and province codes. For apps created after
February 2020, REGION_ID.r is included in
App Engine URLs. For existing apps created before this date, the
region ID is optional in the URL.
Learn more about region IDs.
The queue.yaml configuration file is used to create and configure almost all
of the task queues
(push)
your app uses. All App Engine apps come with
an automatically preconfigured push queue named default. Although you do not
create the default queue yourself, you can add other queues or change the
configuration of the default queue using the queue.yaml file.
To configure push queues, you can use either queue.yaml or
Queue Management methods from Cloud Tasks, but
not both at the same time. Mixing the
queue.yaml upload method with Queue Management methods can produce unexpected
results and is not recommended.
Example
The following a basic example that defines a named queue and overrides the default processing rate:
queue:
- name: my-push-queue
rate: 1/s
The following is a more complex example of a queue.yaml configuration that
demonstrates setting up the number of task tries and modifying the default processing rate.
queue:
- name: fooqueue
rate: 1/s
retry_parameters:
task_retry_limit: 7
task_age_limit: 2d
- name: barqueue
rate: 1/s
retry_parameters:
min_backoff_seconds: 10
max_backoff_seconds: 200
max_doublings: 0
- name: bazqueue
rate: 1/s
retry_parameters:
min_backoff_seconds: 10
max_backoff_seconds: 200
max_doublings: 3
Syntax
The queue.yaml file is a YAML file whose root directive is queue.
This directive contains zero or more named queues. Each queue definition can
specify the following elements:
| Element | Description |
|---|---|
bucket_size (push queues) |
Optional. A task queue uses the token bucket algorithm to control the rate of task execution. Each named queue has a token bucket that holds tokens, up to the maximum specified by the bucket_size value. Each time your application executes a task, a token is removed from the bucket. You continue processing tasks in the queue until the queue's bucket runs out of tokens. App Engine refills the bucket with new tokens continuously based on the rate that you specified for the queue. The bucket size limits how fast the queue is processed when many tasks are in the queue and the rate is high. The maximum value for bucket size is 500. This allows you to have a high rate so processing starts shortly after a task is enqueued, but still limit resource usage when many tasks are enqueued in a short period of time. If you don't specify bucket_size for a queue, the default value is 5. We recommend that you set this to a larger value because the default size might be too small for many use cases. For example, you could determine your bucket size based on the processing rate. For more information on this element, see the comparative description of
|
max_concurrent_requests (push queues) |
Optional. Sets the maximum number of tasks that can be executed simultaneously from the specified queue. The value is an integer. By default, the limit is 1000 tasks per queue. The upper recommended limit is 5000 tasks per queue. Note that queues may slowly ramp up when they are first created or if they have been idle for a while. Restricting the number of concurrent tasks gives you more control over the queue's rate of execution and can prevent too many tasks from running at once. It can also prevent datastore contention and make resources available for other queues or online processing. For more information on this element, see the comparative description of
|
name |
Required. The name of the queue. A queue name can contain uppercase and lowercase letters, numbers, and hyphens. The maximum length for a queue name is 100 characters.
All apps have a push queue named default. This queue has a preset rate
of 5 tasks per second. Note that this default queue doesn't display in
the Google Cloud console until the first time it is used or configured.
You can configure the default queue, including changing the default rate,
by defining a queue named `default` in your |
rate (push queues) |
Required.
How often tasks are processed on this queue. The value is a number
followed by a slash and a unit of time, where the unit is
If the number is For more information on this element, see the comparative description of
|
retry_parameters |
Optional. Configures retry attempts for failed tasks in push queues. This addition allows you to specify the maximum number of times to retry failed tasks in a specific queue. You can also set a time limit for retry attempts and control the interval between attempts. The retry parameters can contain the following subelements:
|
target (push queues) |
Optional. A string naming a service/version, a frontend version, or a backend, on which to execute all of the tasks enqueued onto this queue. The default value is the empty string.
The string is prepended to the domain name of your app when
constructing the HTTP request for a task. For example, if your app ID
is If target is unspecified, then tasks are invoked on the same version of the application where they were enqueued. So, if you enqueued a task from the default application version without specifying a target on the queue, the task is invoked in the default application version. Note that if the default application version changes between the time that the task is enqueued and the time that it executes, then the task will run in the new default version. If you are using services along with a dispatch file, your task's HTTP request might be intercepted and re-routed to another service. |
The following elements can be specified for all queues within an app:
| Element | Description |
|---|
Deploying the queue configuration file
Thequeue.yaml file should reside in the root directory or in the
directory that defines the default service.
To deploy the queue configuration file, run the following command:
gcloud app deploy queue.yaml
Deleting queues
To delete a queue:
Remove the queue definition from your
queue.yamlfile.Upload the change to your
queue.yamlfile.gcloud app deploy queue.yaml
Delete the queue in the Google Cloud console, select the queue and click Delete queue:
If you delete a queue from the Google Cloud console, you must wait 7 days before recreating with the same name.