Chapter 115. RabbitMQ
RabbitMQ Component
Available as of Camel 2.12
The rabbitmq: component allows you produce and consume messages from RabbitMQ instances. Using the RabbitMQ AMQP client, this component offers a pure RabbitMQ approach over the generic AMQP component.
Maven users will need to add the following dependency to their
pom.xml
for this component:
<dependency> <groupId>org.apache.camel</groupId> <artifactId>camel-rabbitmq</artifactId> <version>x.x.x</version> <!-- use the same version as your Camel core version --> </dependency>
URI format
rabbitmq://hostname[:port]/exchangeName?[options]
Where hostname is the hostname of the running rabbitmq instance or cluster. Port is optional and if not specified then defaults to the RabbitMQ client default (5672). The exchange name determines which exchange produced messages will sent to. In the case of consumers, the exchange name determines which exchange the queue will bind to.
Options
Property | Default | Description |
---|---|---|
autoAck
|
true
|
If messages should be auto acknowledged. |
autoDelete
|
true
|
If true, the exchange will be deleted when it is no longer in use. |
durable
|
true
|
If we are declaring a durable exchange (the exchange will survive a server restart). |
queue
|
random uuid
|
The queue to receive messages from. |
routingKey
|
null
|
The routing key to use when binding a consumer queue to the exchange. For producer routing keys, you set the header (see header section). |
threadPoolSize
|
10
|
The consumer uses a Thread Pool Executor with a fixed number of threads. This setting allows you to set that number of threads. |
username
|
null
|
username in case of authenticated access. |
password
|
null
|
password for authenticated access. |
vhost
|
/
|
the vhost for the channel. |
exchangeType
|
direct
|
Camel 2.12.2: The exchange type such as direct or topic.
|
bridgeEndpoint
|
false
|
Camel 2.12.3: If the bridgeEndpoint is true, the producer will ignore the message header of "rabbitmq.EXCHANGE_NAME" and "rabbitmq.ROUTING_KEY"
|
addresses
|
null
|
Camel 2.12.3: If this option is set, camel-rabbitmq will try to create connection based on the setting of option addresses. The addresses value is a string which looks like "server1:12345, server2:12345".
|
connectionTimeout
|
0
|
Camel 2.14: Connection timeout.
|
requestedChannelMax
|
0
|
Camel 2.14: Connection requested channel max (max number of channels offered).
|
requestedFrameMax
|
0
|
Camel 2.14: Connection requested frame max (max size of frame offered).
|
requestedHeartbeat
|
0
|
Camel 2.14: Connection requested heartbeat (heart-beat in seconds offered).
|
sslProtocol
|
null
|
Camel 2.14: Enables SSL on connection, accepted value are `true`, `TLS` and 'SSLv3`
|
trustManager
|
null
|
Camel 2.14: Configure SSL trust manager, SSL should be enabled for this option to be effective.
|
clientProperties
|
null
|
Camel 2.14: Connection client properties (client info used in negotiating with the server).
|
connectionFactory
|
null
|
Camel 2.14: Custom RabbitMQ connection factory. When this option is set, all connection options (connectionTimeout, requestedChannelMax...) set on URI are not used.
|
automaticRecoveryEnabled
|
false
|
Camel 2.14: Enables connection automatic recovery (uses connection implementation that performs automatic recovery when connection shutdown is not initiated by the application).
|
networkRecoveryInterval
|
5000
|
Camel 2.14: Network recoverty interval in milliseconds (interval used when recovering from network failure).
|
topologyRecoveryEnabled
|
true
|
Camel 2.14: Enables connection topology recovery (should topology recovery be performed?).
|
prefetchEnabled
|
false
|
Camel 2.14: Enables the quality of service on the RabbitMQConsumer side, you need to specify the option of prefetchSize, prefetchCount, prefetchGlobal at the same time
|
prefetchSize
|
0
|
Camel 2.14: The maximum amount of content (measured in octets) that the server will deliver, 0 if unlimited.
|
prefetchCount
|
0
|
Camel 2.14: The maximum number of messages that the server will deliver, 0 if unlimited.
|
prefetchGlobal
|
false
|
Camel 2.14: If the settings should be applied to the entire channel rather than each consumer.
|
declare
|
true
|
Camel 2.14: If the option is true, camel declare the exchange and queue name and bind them together. If the option is false, camel won't declare the exchange and queue name on the server. |
concurrentConsumers
|
1
|
Camel 2.14: Number of concurrent consumers when consuming from broker. (eg similar as to the same option for the JMS component). |
deadLetterRoutingKey
|
Camel 2.14: The routing key for the dead letter exchange. | |
deadLetterExchange
|
Camel 2.14: The name of the dead letter exchange. | |
deadLetterExchangeType
|
direct
|
Camel 2.14: The type of the dead letter exchange. |
channelPoolMaxSize
|
10
|
Camel 2.14.1 (Producer only): Maximum number of channels used to send messages. |
channelPoolMaxWait
|
1000
|
Camel 2.14.1 (Producer only): Maximum time (in milliseconds) waiting for a channel. |
queueArgsConfigurer
|
null
|
Camel 2.15.1: The custom ArgsConfigurer instance which could be used to configure the Args map when declaring the queue.
|
exchangeArgsConfigurer
|
null
|
Camel 2.15.1: The custom ArgsConfigurer instance which could be used to configure the Args map when declaring the exchange.
|
Custom connection factory
<bean id="customConnectionFactory" class="com.rabbitmq.client.ConnectionFactory"> <property name="host" value="localhost"/> <property name="port" value="5672"/> <property name="username" value="camel"/> <property name="password" value="bugsbunny"/> </bean> <camelContext> <route> <from uri="direct:rabbitMQEx2"/> <to uri="rabbitmq://localhost:5672/ex2?connectionFactory=#customConnectionFactory"/> </route> </camelContext>
Headers
The following headers are set on exchanges when consuming messages.
Property | Value |
---|---|
rabbitmq.ROUTING_KEY
|
The routing key that was used to receive the message, or the routing key that will be used when producing a message |
rabbitmq.EXCHANGE_NAME
|
The exchange the message was received from |
rabbitmq.DELIVERY_TAG
|
The rabbitmq delivery tag of the received message |
rabbitmq.REQUEUE
|
Camel 2.14.2: This is used by the consumer to control rejection of the message. When the consumer is complete processing the exchange, and if the exchange failed, then the consumer is going to reject the message from the RabbitMQ broker. The value of this header controls this behaviour. If false , the message is discarded/dead-lettered. If true , the message is re-queued. Default is false .
|
The following headers are used by the producer. If these are set on the camel exchange then they will be set on the RabbitMQ message.
Property | Value |
---|---|
rabbitmq.ROUTING_KEY
|
The routing key that will be used when sending the message |
rabbitmq.EXCHANGE_NAME
|
The exchange the message was received from, or sent to |
rabbitmq.CONTENT_TYPE
|
The contentType to set on the RabbitMQ message |
rabbitmq.PRIORITY
|
The priority header to set on the RabbitMQ message |
rabbitmq.CORRELATIONID
|
The correlationId to set on the RabbitMQ message |
rabbitmq.MESSAGE_ID
|
The message id to set on the RabbitMQ message |
rabbitmq.DELIVERY_MODE
|
If the message should be persistent or not |
rabbitmq.USERID
|
The userId to set on the RabbitMQ message |
rabbitmq.CLUSTERID
|
The clusterId to set on the RabbitMQ message |
rabbitmq.REPLY_TO
|
The replyTo to set on the RabbitMQ message |
rabbitmq.CONTENT_ENCODING
|
The contentEncoding to set on the RabbitMQ message |
rabbitmq.TYPE
|
The type to set on the RabbitMQ message |
rabbitmq.EXPIRATION
|
The expiration to set on the RabbitMQ message |
rabbitmq.TIMESTAMP
|
The timestamp to set on the RabbitMQ message |
rabbitmq.APP_ID
|
The appId to set on the RabbitMQ message |
Headers are set by the consumer once the message is received. The producer will also set the headers for downstream processors once the exchange has taken place. Any headers set prior to production that the producer sets will be overriden.
Message Body
The component will use the camel exchange in body as the rabbit mq message body. The camel exchange in object must be convertible to a byte array. Otherwise the producer will throw an exception of unsupported body type.
Samples
To receive messages from a queue that is bound to an exchange A with the routing key B,
from("rabbitmq://localhost/A?routingKey=B")
To receive messages from a queue with a single thread with auto acknowledge disabled.
from("rabbitmq://localhost/A?routingKey=B&threadPoolSize=1&autoAck=false")
To send messages to an exchange called C
...to("rabbitmq://localhost/B")