Configure SMQ as an event stream source - EventBridge

When messages arrive in a Simple Message Queue (formerly MNS) (SMQ) queue, you may need to route them to downstream services such as Function Compute for processing. EventBridge event streams connect an SMQ queue to a target service so that messages are delivered automatically without polling or custom integrations.

Prerequisites

Before you begin, make sure that you have:

An activated EventBridge instance with the required permissions granted to a Resource Access Management (RAM) user. For more information, see Activate EventBridge and grant permissions to a RAM user
An SMQ queue. For more information, see Activate SMQ and authorize RAM users to access SMQ

Create an event stream with an SMQ source

Log on to the EventBridge console. In the left-side navigation pane, click Event Streams.
In the top navigation bar, select a region and click Create Event Stream.
On the Create Event Stream page, specify the Task Name and Description parameters.
Configure the event source, filtering, transformation, sink, and task properties as described in the following sections. Then click Save.

Source

In the Source step, set Data Provider to SMQ and configure the following parameters. Then click Next Step.

Parameter	Description	Valid values	Example
Queue Name	The SMQ queue to use as the event source.	N/A	test-queue
Base64 Decoding	Whether to decode message data from Base64 before delivery to the sink. Enable this if your SMQ messages are Base64-encoded.	N/A	test
Messages	The maximum number of messages that can be sent in each function invocation. Requests are sent only when the number of messages in the backlog reaches the specified value.	1 to 10,000	100
Interval (Unit: Seconds)	The time interval at which you want to invoke the function. The system sends the aggregated messages to Function Compute when the specified interval is reached. Set to 0 to send messages immediately after aggregation.	0 to 15	3

Filtering, transformation, and sink

In the Filtering, Transformation, and Sink steps, configure the event filtering method, event transformation rule, and event target.

For more information about event transformation, see Use Function Compute to perform message cleansing.

Retry policy and dead-letter queue

Under Task Property, specify the retry policy and dead-letter queue for the event stream.

For more information, see Retry policies and dead-letter queues.

Enable the event stream

Go back to the Event Streams page and find the event stream that you created.
In the Actions column, click Enable.

The event stream takes 30 to 60 seconds to start. Track the progress in the Status column on the Event Streams page.

Sample event

Each message from the SMQ queue is delivered as a CloudEvents 1.0-compliant event. The following example shows the structure of a typical event:

{
    "specversion": "1.0",
    "id": "bffb9722-9c48-407b-9895-b038f78f****",
    "source": "acs:mns",
    "type": "mns:Queue:SendMessage",
    "subject": "acs:mns:cn-hangzhou:123456789098****:queues/zeus",
    "datacontenttype": "application/json; charset=utf-8",
    "time": "2021-04-08T06:28:17.093Z",
    "aliyunpublishtime": "2021-04-08T06:30:31.367Z",
    "aliyuneventbusname": "mybus",
    "data": {
        "requestId": "606EA3074344430D4C81****",
        "messageId": "C6DB60D1574661357FA227277445****",
        "messageBody": "TEST"
    }
}

For more information about the CloudEvents envelope fields (specversion, id, source, type, subject, time, and others), see Overview.

Data fields

The data object contains the original SMQ message payload:

Field	Type	Description
`requestId`	String	A unique identifier for the request that sent the message to the queue.
`messageId`	String	A unique identifier for the message in the queue.
`messageBody`	String	The message body content.

EventBridge:Configure Simple Message Queue (formerly MNS) as an event source