Creating Triggers

Last updated: 2020-07-10 10:45:18

    After creating a function, you can create a trigger to associate the function with an event source. The associated event source will trigger the function synchronously or asynchronously as specified when an event is generated, and the event will be passed to the entry function as an input parameter upon triggering.

    A function trigger can be created in the console or through Serverless Framework CLI.

    Creating Trigger in Console

    1. Log in to the SCF Console and select Function Service on the left sidebar.
    2. At the top of the "Function Service" page, select the region and namespace where the function for which to create a trigger resides as shown below:

      The function list contains the function name, monitoring information, runtime environment, creation time, and modification time.
    3. Click the function name to enter the function details page.
      The function details page contains the function configuration, function code, triggers, logs, and monitoring tabs.
    4. Select the Triggers tab to enter the trigger browsing and operation page. Click Add Trigger to create a trigger as shown below:
    5. In the expanded "Add Trigger" form, you can select different trigger types in Trigger Type. The information to be entered varies by trigger type.
      For example, for a timer trigger, you need to enter the trigger name, cycle, and status. For a COS trigger, you need to enter the COS bucket, event type, and prefix/suffix filters.

      For more information on what to enter for specific triggers, please see the applicable documents of triggers.

    6. After completing the configuration, click Save to create the trigger.

      To cancel the creation process, click Cancel.

    Creating Trigger Through Serverless Framework CLI

    Before starting, please install the Serverless Framework CLI tool first as instructed in Installing Serverless Framework.

    For local functions, please add the trigger description in the serverless.yml file. Then, run the sls deploy command on Serverless Framework CLI to add a trigger to the function.

    Version and Trigger

    A trigger can be created on a specified version of a function. An event of the trigger created in this manner will trigger the code on the specified version.

    When creating such a trigger in the console, you can switch to the desired version by choosing it in the version list in the top-right corner on the function page and then create the trigger on the "Triggers" tab.

    There are certain quota limits for the total number of triggers and number of triggers in each type for a function. Based on the function configuration, triggers created on different versions take up the quota of the function. To increase the limit, please contact us for application.