Function Compute:Asynchronous tasks

Enable task mode when creating a function

1. Log on to the Function Compute console. In the left-side navigation pane, choose Function Management > Function.

2. In the top navigation bar, select a region. On the Function page, click Create Function.

3. In the dialog box, select Task Function and click Create. Set the function name and click Create.

4. After the function is created, go to the function details page and click the Tasks tab. Task mode is enabled by default.

For configuration details, see Create a task function.

Enable task mode on an existing function

Before you begin, ensure that you have created a function. See Create a function.

1. Log on to the Function Compute console. In the left-side navigation pane, click Functions.

2. In the top navigation bar, select a region. On the Functions page, click the target function.

3. On the function details page, click the Tasks tab, then click Modify next to Task Mode.

4. In the Task Mode panel, set Task Mode to Enable and click Deploy.

Enable task mode via API

Call PutFunctionAsyncInvokeConfig with asyncTask set to true. All subsequent asynchronous invocations for the function use task mode.

{
  "asyncTask": true
}

Submit a task from the console

1. Log on to the Function Compute console. In the left-side navigation pane, click Functions.

2. In the top navigation bar, select a region. On the Functions page, click the target function.

3. On the function details page, click the Tasks tab, then click Submit Task.

4. In the dialog box, select a task ID generation method and specify the execution time, then click OK.

To pass test parameters before submitting, click the arrow icon next to Submit Task and select Configure Test Parameters. For event functions, parameters are passed as an event payload. For HTTP functions, parameters are passed as HTTP parameters.

After submission, the task list shows Task Status, Task ID, and Instance ID.

Submit a task via API

Call InvokeFunction with the x-fc-invocation-type header set to Async. To assign a custom task ID for deduplication, include the x-fc-async-task-id header.

Example: submit a task and poll its status

The following example shows the complete lifecycle of submitting an asynchronous task and querying its status until it completes.

1. Enable task mode on the function (one-time setup):

   PUT /2023-03-30/functions/{functionName}/async-invoke-config
   Content-Type: application/json
   
   {
     "asyncTask": true
   }

2. Submit the task with a custom task ID:

   POST /2023-03-30/functions/{functionName}/invocations
   x-fc-invocation-type: Async
   x-fc-async-task-id: my-task-001

3. Query the task status using the task ID:

   GET /2023-03-30/functions/{functionName}/async-tasks/my-task-001

   The response includes the current status (Enqueued, Running, Succeeded, etc.). Poll this endpoint until the status reaches a terminal state.

For a runnable code sample that sets a task ID during invocation, see InvokeFunction sample (international site).

Stop a task from the console

On the Tasks tab of the function details page, locate the task in the task list and stop it.

Stop a task via API

Call StopAsyncTask with the task's TaskID. To find the TaskID, call ListAsyncTasks.

View metrics

Before you begin, ensure that you have created a function. See Create a function.

1. Log on to the Function Compute console. In the left-side navigation pane, click Functions.

2. In the top navigation bar, select a region. On the Function page, click the target function.

3. On the function details page, click the Monitoring tab.

   • Click Function Metrics to view asynchronous invocation metrics: Asynchronous Invocation Processing (count), Asynchronous Invocation Processing Latency (ms), Asynchronous Invocation Trigger Events (count), and Asynchronous Requests Backlogs (count).

   • Click Instance Metrics to view instance-level resource usage for asynchronous task instances.

For a full list of monitoring metrics, see Monitoring metrics.

Set alert rules

To set an alert on a metric, click the bell icon in the upper-right corner of the metric chart. Set the alert conditions and threshold in the Create Metric-based Alert Rule panel, then click OK.

Example: send a medium-severity alert when backlogged asynchronous invocations reach 5 or more, delivered 24/7 via DingTalk, email, phone, and webhook.

Prerequisites

Before you begin, ensure that you have:

• An asynchronous task enabled (see Enable task mode)

• Granted CloudFlow access to Function Compute. See Use a function role to grant Function Compute permissions to access other cloud services

Create and run a workflow

1. Log on to the CloudFlow console. In the top navigation bar, select a region.

2. In the left-side navigation pane, click Workflows. On the Workflows page, click Create Workflow.

3. In the Create Workflow dialog box, select a creation method and workflow mode. CloudFlow supports two modes: Standard and Express. See Standard workflows and Express workflows and Create a workflow from a blank canvas for details.

4. Define the workflow. In the upper-right corner of the flow details page, click YAML. Enter the flow definition in the code editor, then click Save. The following example invokes a Function Compute function asynchronously and waits for it to complete before the workflow ends (TaskMode: RequestComplete):

   Type: StateMachine
   Name: MyFlow
   SpecVersion: v1
   StartAt: InvokeFunction
   States:
     - Type: Task
       Name: InvokeFunction
       Action: FC:InvokeFunction
       TaskMode: RequestComplete
       Parameters:
         invocationType: Async
         resourceArn: acs:fc:us-west-1:103435468****:functions/func-i1****/LATEST
       End: true

5. Configure the execution role. In the upper-right corner, click Configure Workflow. Select an Execution Role and click Save.

   Note

   The role must be attached to the AliyunFCInvocationAccess policy.

6. On the flow details page, click Execute to test the workflow.