For using the Spring Cloud Alibaba RocketMQ Binder, you just need to add it to your Spring Cloud Stream application, using the following Maven coordinates:
The core of RocketMQ Binder are the 3 classes below: `RocketMQMessageChannelBinder`，`RocketMQInboundChannelAdapter` and `RocketMQMessageHandler`.
Alternatively, you can also use the Spring Cloud Stream RocketMQ Starter:
`RocketMQMessageChannelBinder` is a standard implementation of Binder. It contains `RocketMQInboundChannelAdapter` and `RocketMQMessageHandler` as its internal constructions.
`RocketMQMessageHandler` is used to start RocketMQ `Producer` and send messages. It creates message type of RocketMQ `org.apache.rocketmq.common.message.Message` based on the message type of `org.springframework.messaging.Message` in the `spring-messaging` module.
### How Spring Cloud Alibaba RocketMQ Binder Works
When constructing `org.apache.rocketmq.common.message.Message`, it constructs `RocketMQMessageHeaderAccessor` based on the header of `org.springframework.messaging.Message`. Then, based on some of the properties in `RocketMQMessageHeaderAccessor` , it sets some of message attributes such as tags, keys, and flag in `org.apache.rocketmq.common.message.Message` of RocketMQ.
The implementation of RocketMQ Binder depend on the https://github.com/apache/rocketmq-spring[RocketMQ-Spring] framework.
`RocketMQInboundChannelAdapter` is used to start RocketMQ `Consumer` and receive messages. It also support the usage of https://github.com/spring-projects/spring-retry[spring-retry].
RocketMQ Spring framework is an integration of RocketMQ and Spring Boot. It provides three main features:
You can also obtain `Acknowledgement` from the Header and make some configurations.
1. `RocketMQTemplate`: Sending messages, including synchronous, asynchronous, and transactional messages.
2. `@RocketMQTransactionListener`: Listen and check for transaction messages.
3. `@RocketMQMessageListener`: Consume messages.
For example, you can set delayed message consumption when `MessageListenerConcurrently` is used for asynchronous message consumption:
`RocketMQMessageChannelBinder` is a standard implementation of Binder, it will build `RocketMQInboundChannelAdapter` and `RocketMQMessageHandler` internally.
```java
@StreamListener("input")
public void receive(Message message) {
RocketMQMessageHeaderAccessor headerAccessor = new RocketMQMessageHeaderAccessor(message);
`RocketMQMessageHandler` will construct `RocketMQTemplate` based on the Binding configuration. `RocketMQTemplate` will convert the `org.springframework.messaging.Message` message class of `spring-messaging` module to the RocketMQ message class `org.apache.rocketmq.common .message.Message` internally, then send it out.
You can also set delayed message consumption when `MessageListenerOrderly` is used for consuming ordered messages.
`RocketMQInboundChannelAdapter` will also construct `RocketMQListenerBindingContainer` based on the Binding configuration, and `RocketMQListenerBindingContainer` will start the RocketMQ `Consumer` to receive the messages.
```java
@StreamListener("input")
public void receive(Message message) {
RocketMQMessageHeaderAccessor headerAccessor = new RocketMQMessageHeaderAccessor(message);
NOTE: RocketMQ Binder Application can also be used to configure rocketmq.** to trigger RocketMQ Spring related AutoConfiguration
Supported Configurations of Provider:
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|====
^|Configuration ^|Description ^| Default Value
|`spring.cloud.stream.rocketmq.bindings.your-output-binding.producer.enabled`|Whether to use producer|true
|`spring.cloud.stream.rocketmq.bindings.your-output-binding.producer.max-message-size`|Maximum bytes of messages sent|0(Take effect only when it’s bigger than 0. The default value of RocketMQ is 4M = 1024 * 1024 * 4)
|`spring.cloud.stream.rocketmq.bindings.your-output-binding.producer.transactional`|Whether to use `TransactionMQProducer` to send transaction messages|false
|`spring.cloud.stream.rocketmq.bindings.your-output-binding.producer.executer`|Full class name of the interface implementation class related to `org.apache.rocketmq.client.producer.LocalTransactionExecuter` For example, `org.test.MyExecuter`|
|`spring.cloud.stream.rocketmq.bindings.your-output-binding.producer.transaction-check-listener`|Full class name of the interface implementation class related to `org.apache.rocketmq.client.producer.TransactionCheckListener` For example, `org.test.MyTransactionCheckListener`|
|====
Supported Configurations of Consumer:
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|====
^|Configuration ^|Description| Default Value
|`spring.cloud.stream.rocketmq.bindings.your-input-binding.consumer.enabled`|Whether to use consumer|true
|`spring.cloud.stream.rocketmq.bindings.your-input-binding.consumer.tags`|Consumer will only subscribe to messages with these tags Tags are separated by "\|\|" (If not specified, it means the consumer subscribes to all messages)|
|`spring.cloud.stream.rocketmq.bindings.your-input-binding.consumer.sql`|Consumer subscribes to the messages as requested in the SQL(If tags are also specified, SQL has a higher priority than tags.)|
|`spring.cloud.stream.rocketmq.bindings.your-input-binding.consumer.broadcasting`|If the consumer uses the broadcasting mode|false
|`spring.cloud.stream.rocketmq.bindings.your-input-binding.consumer.orderly`|Ordered message consumption or asychronous consumption|false
|====
### Endpoint Support
Before you use the Endpoint feature, please add the `spring-boot-starter-actuator` dependency in Maven, and enable access of Endpoints in your configuration.
* Add `management.security.enabled=false`in Spring Boot 1.x. The exposed endpoint path is `/rocketmq_binder`
* Add `management.endpoints.web.exposure.include=*`in Spring Boot 2.x. The exposed endpoint path is `/actuator/rocketmq-binder`
Endpoint will collects data about the last message that is sent, the number of successes or failures of message sending, and the number of successes of failures of message consumption.
The headers defined in `RocketMQHeaders`, which can be set to the header of spring message when sending a message to trigger the RocketMQ related feature:
Note： To view statistics, add the https://mvnrepository.com/artifact/io.dropwizard.metrics/metrics-core[metrics-core dependency] in POM. If not added, the endpoint will return warning instead of statistics:
The following properties are available for RocketMQ producers only and must be prefixed with `spring.cloud.stream.rocketmq.bindings.<channelName>.consumer.`.
enable::
Enable Consumer Binding.
+
Default: `true`.
tags::
Consumer subscription tags expression, tags split by `||`.
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Default: empty.
sql::
Consumer subscription sql expression.
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Default: empty.
broadcasting::
Control message mode, if you want all subscribers receive message all message, broadcasting is a good choice.
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Default: `false`.
orderly::
Receiving message concurrently or orderly.
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Default: `false`.
delayLevelWhenNextConsume::
Message consume retry strategy for concurrently consume:
* -1,no retry,put into DLQ directly
* 0,broker control retry frequency
* >0,client control retry frequency
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Default: `0`.
suspendCurrentQueueTimeMillis::
Time interval of message consume retry for orderly consume.
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Default: `1000`.
#### RocketMQ Provider Properties
The following properties are available for RocketMQ producers only and must be prefixed with `spring.cloud.stream.rocketmq.bindings.<channelName>.producer.`.
enable::
Enable Producer Binding.
+
Default: `true`.
group::
Producer group name.
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Default: empty.
maxMessageSize::
Maximum allowed message size in bytes.
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Default: `8249344`.
transactional::
Send Transactional Message.
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Default: `false`.
sync::
Send message in synchronous mode.
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Default: `false`.
vipChannelEnabled::
Send message with vip channel.
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Default: `true`.
sendMessageTimeout::
Millis of send message timeout.
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Default: `3000`.
compressMessageBodyThreshold::
Compress message body threshold, namely, message body larger than 4k will be compressed on default.
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Default: `4096`.
retryTimesWhenSendFailed::
Maximum number of retry to perform internally before claiming sending failure in synchronous mode.
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Default: `2`.
retryTimesWhenSendAsyncFailed::
Maximum number of retry to perform internally before claiming sending failure in asynchronous mode.
+
Default: `2`.
retryNextServer::
Indicate whether to retry another broker on sending failure internally.
fangjian0423
6 years ago