ApsaraMQ for RocketMQ:Message retry

Retry timing

The interval between two consecutive consumption attempts has three components:

Interval between attempts = consumption duration + retry interval + time in Ready state

For example, assume a message waits 5 seconds in the Ready state and takes 6 seconds to process before failing. With a 10-second retry interval:

1. 0 s -- The message enters the Ready state.

2. 5 s -- The consumer pulls the message (Inflight).

3. 11 s -- Consumption fails after 6 seconds. The message enters WaitingRetry.

4. 21 s -- After the 10-second retry interval, the message returns to Ready.

5. 26 s -- The consumer pulls the message again for the next attempt.

Total interval: 6 + 10 + 5 = 21 seconds.

Ordered messages

Unordered messages

If MaxReconsumeTimes exceeds 16, the predefined schedule applies for the first 16 retries. All subsequent retries use a fixed 2-hour interval.

Enable retry

To trigger a retry when consumption fails in clustering consumption mode, implement the MessageListener interface with one of these approaches:

• Return Action.ReconsumeLater (recommended)

• Return null

• Throw an exception

public class MessageListenerImpl implements MessageListener {

    @Override
    public Action consume(Message message, ConsumeContext context) {
        // If the consumption logic throws an exception, the message is retried.
        doConsumeMessage(message);
        // Method 1: Return Action.ReconsumeLater and retry the message.
        return Action.ReconsumeLater;
        // Method 2: Return null and retry the message.
        return null;
        // Method 3: Throw an exception and retry the message.
        throw new RuntimeException("Consumer Message exception");
    }
}

Disable retry

To prevent redelivery, catch all exceptions in your consumption logic and return Action.CommitMessage:

public class MessageListenerImpl implements MessageListener {

    @Override
    public Action consume(Message message, ConsumeContext context) {
        try {
            doConsumeMessage(message);
        } catch (Throwable e) {
            // Catch all exceptions and return CommitMessage to skip retry.
            return Action.CommitMessage;
        }
        // Consumption succeeded.
        return Action.CommitMessage;
    }
}

Customize the retry interval and maximum retries

Set MaxReconsumeTimes and SuspendTimeMillis in the consumer properties before starting the consumer. Custom retry intervals apply only to ordered messages. Unordered messages always follow the predefined schedule.

Properties properties = new Properties();
// Set the maximum number of retries to 20.
properties.put(PropertyKeyConst.MaxReconsumeTimes, "20");
// Set the retry interval to 3,000 milliseconds (ordered messages only).
properties.put(PropertyKeyConst.SuspendTimeMillis, "3000");
Consumer consumer = ONSFactory.createConsumer(properties);

Query the retry count

After a consumer receives a message, call message.getReconsumeTimes() to check how many times the message has been retried:

public class MessageListenerImpl implements MessageListener {

    @Override
    public Action consume(Message message, ConsumeContext context) {
        // Get the current retry count.
        System.out.println(message.getReconsumeTimes());
        return Action.CommitMessage;
    }
}