Configure an event rule to route custom events to ApsaraMQ for RocketMQ - EventBridge

EventBridge event rules filter events from a custom event source and route matching events to ApsaraMQ for RocketMQ as messages. Use event transformation to control the message body, custom properties, message key, and message tag delivered to the target topic.

This topic walks through the full workflow: adding a custom event source, creating an event rule with ApsaraMQ for RocketMQ as the target, publishing a test event, and verifying delivery.

Prerequisites

Before you begin, make sure that you have:

Step 1: Add a custom event source

Log on to the EventBridge console.
In the left-side navigation pane, click Event Buses.
In the top navigation bar, select a region. Click the name of the custom event bus that you want to use.
In the left-side navigation pane, click Event Sources, then click Add Event Source.
In the Add Custom Event Source panel, set Name and Description, select Custom Application from the Event Provider drop-down list, and click OK.

Step 2: Create an event rule

Important

Event targets must reside in the same region as the event rule.

Log on to the EventBridge console.
In the left-side navigation pane, click Event Buses.
In the top navigation bar, select a region. Click the name of the event bus that you want to use.
In the left-side navigation pane, click Event Rules, then click Create Rule.
In the Create Rule panel, complete the following steps:
1. Configure Basic Info: Enter a rule name and description, then click Next Step.
2. Configure Event Pattern: Set Event Source Type to Custom Event Source, select the event source created in Step 1 from the Event Source drop-down list, specify an event pattern in the Pattern Content code editor, and click Next Step. For supported filter types (exact match, prefix, suffix, and more), see Event patterns.
3. Configure Targets: Select ApsaraMQ for RocketMQ as the service type and configure the target parameters described in the following section, then click Create.

Note

Each event rule supports up to five event targets.

ApsaraMQ for RocketMQ target parameters

The following table lists the parameters available when you select ApsaraMQ for RocketMQ as the event target. Each parameter uses a transformation method to extract or construct values from the incoming event.

Parameter	Description
Service Type	Select ApsaraMQ for RocketMQ.
Instance ID	Select the ID of the ApsaraMQ for RocketMQ instance.
Topic	Select the topic to receive events.
Message Body	The content extracted from the event and sent as the message body. Specify with a transformation method.
Custom Property	Key-value pairs extracted from the event and attached as message properties. Specify with a transformation method.
Message Index	The value extracted from the event and set as the message key. Specify with a transformation method.
Message Tag	The value extracted from the event and set as the message tag. Specify with a transformation method.

Event transformation methods

EventBridge transforms event data before delivering it to the target. Each target field (Message Body, Custom Property, Message Index, Message Tag) supports the following methods. For full details, see Event transformation.

Partial event

Extract a single value from the event using a JSONPath expression.

Configuration:

$.data.body

Result -- Given the sample event in Verify the result, this returns "TEST".

Fixed value

Deliver a static string regardless of event content.

Configuration:

Pay attention to the alert.

Result -- Every event delivers the string Pay attention to the alert. as-is.

Parameters and template

Define variables from the event using JSONPath, then assemble them into a structured output.

Step 1 -- Define variables in Parameters:

{
  "type": "$.type"
}

Step 2 -- Reference variables in Template:

The event type is ${type}.

Result -- Given an event where $.type is mq:Topic:SendMessage, this produces:

The event type is mq:Topic:SendMessage.

Example: Forward user properties and message keys

To forward RocketMQ user properties and the unique message key from the source event, configure Custom Property as follows:

Parameters:

{
  "userProperties": "$.data.userProperties",
  "msgId": "$.data.systemProperties.UNIQ_KEY"
}

Template:

{
  "EB_SYS_EMBED_OBJECT": "${userProperties}",
  "UNIQ_KEY": "${msgId}"
}

Result -- Given the sample event in Verify the result, where $.data.userProperties is {} and $.data.systemProperties.UNIQ_KEY is AC14C305069E1B28CDFA3181CDA2****, this produces:

{
  "EB_SYS_EMBED_OBJECT": "{}",
  "UNIQ_KEY": "AC14C305069E1B28CDFA3181CDA2****"
}

Step 3: Publish an event

Log on to the EventBridge console. In the left-side navigation pane, click Event Buses.
In the top navigation bar, select a region.
Find the target event bus and click Publish Event in the Operations column.
Note
The EventBridge console supports publishing events to custom event buses only.
In the Publish Event to Custom Event Bus panel, select a source from the Custom Event Source drop-down list, enter the event content in the Event Body code editor, and click OK. For details about event fields, see Event overview.

Verify the result

Confirm that ApsaraMQ for RocketMQ received the event by querying messages in the RocketMQ console.

Log on to the ApsaraMQ for RocketMQ console.
In the left-side navigation pane, click Instances.
In the top navigation bar, select the region where the instance resides (for example, China (Hangzhou)).
Find the target instance and choose More > Message Query in the Actions column.
On the Message Query page, set Query Method to Query by Topic, select the topic, set the Time Range, and click Search.

The following example shows a received event:

{
    "id": "94ebc15f-f0db-4bbe-acce-56fb72fb****",
    "source": "acs:mq",
    "specversion": "1.0",
    "type": "mq:Topic:SendMessage",
    "datacontenttype": "application/json; charset=utf-8",
    "subject": "acs:mq:cn-hangzhou:123456789098****:MQ_INST_123456789098****_BXhFHryi%TopicName",
    "time": "2021-04-08T06:01:20.766Z",
    "aliyunpublishtime": "2021-04-08T06:01:20.725Z",
    "aliyuneventbusname": "BusName",
    "data": {
        "topic": "TopicName",
        "systemProperties": {
            "MIN_OFFSET": "0",
            "TRACE_ON": "true",
            "MAX_OFFSET": "8",
            "MSG_REGION": "cn-hangzhou",
            "KEYS": "systemProperties.KEYS",
            "CONSUME_START_TIME": 1628577790396,
            "UNIQ_KEY": "AC14C305069E1B28CDFA3181CDA2****",
            "TAGS": "systemProperties.TAGS",
            "INSTANCE_ID": "MQ_INST_123456789098****_BXhFHryi"
        },
        "userProperties": {},
        "body": "TEST"
    }
}

EventBridge:Route events to ApsaraMQ for RocketMQ