Function Compute:Self-managed Apache RocketMQ triggers

How it works

When you create a trigger in Function Compute, Function Compute automatically creates a corresponding event stream in EventBridge based on your configuration. View the trigger details in the Function Compute console and the automatically created resources in the EventBridge console.

Prerequisites

Before you begin, ensure that you have:

• EventBridge activated with the required permissions granted

• A Function Compute function created

• A self-managed Apache RocketMQ cluster deployed and accessible. To quickly deploy a cluster and start sending and receiving messages, see the quick start for your version:

  • Apache RocketMQ 5.0: Quick startQuick start

  • Apache RocketMQ 4.x: Quick startQuick start

• A topic created in your RocketMQ instance

• A consumer group created in your RocketMQ instance

Limitations

• The RocketMQ instance must be accessible over the public internet or from an Alibaba Cloud Virtual Private Cloud (VPC).

• If the instance is accessed from a VPC, the VPC must be in the same region as your function. Make sure the security group allows inbound traffic on the RocketMQ NameServer port (default: 9876).

• The number of RocketMQ triggers is limited by the EventBridge event stream quota. For details, see Limits.

Step 1: Create a trigger

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 function you want to manage.

3. On the function details page, click the Trigger tab, then click Create Trigger.

4. In the Create Trigger panel, configure the parameters described in the following table, then click OK.

For advanced settings such as push configurations, retry policies, and dead-letter queues, see Advanced features of triggers.

After the trigger is created, it appears on the Triggers tab. To modify or delete it, see Manage triggers.

Step 2: Configure a test event

The trigger passes messages from RocketMQ to your function as an array of event objects. Simulate a trigger invocation by manually configuring a test event.

1. On the Code tab of the function details page, click the icon next to Test Function and select Configure Test Parameters.

2. In the Configure Test Parameters panel, select Create new test event or Modify existing test event. Enter an event name, paste the event content below, and click OK.

[
  {
    "msgId": "7F0000010BDD2A84AEE70DA49B57****",
    "topic": "testTopic",
    "systemProperties": {
      "UNIQ_KEY": "7F0000010BDD2A84AEE70DA49B57****",
      "CLUSTER": "DefaultCluster",
      "MIN_OFFSET": "0",
      "TAGS": "TagA",
      "MAX_OFFSET": "128"
    },
    "userProperties": {},
    "body": "Hello RocketMQ"
  }
]

Each object in the array represents one RocketMQ message. The fields are described below.

Step 3: Write and test the function code

After the trigger is created, write your function code to process incoming messages. In production, the trigger automatically invokes the function when RocketMQ receives a new message.

1. On the Code tab of the function details page, write your code in the editor and click Deploy. The following Node.js example reads the event and returns a result:

   'use strict';
   /*
   To enable the initializer feature,
   implement the initializer function as shown below:
   exports.initializer = (context, callback) => {
     console.log('initializing');
     callback(null, '');
   };
   */
   exports.handler = (event, context, callback) => {
     console.log("event: %s", event);
     // Parse the event and process each message.
     callback(null, 'return result');
   }

2. Click Test Function to run the test event you configured in the previous step.

What's next

In addition to the Function Compute console, configure and manage triggers using:

• Serverless Devs: See Common Serverless Devs commands

• SDKs: See SDKs

To modify or delete an existing trigger, see Manage triggers.