NATS Component

Table of Contents

URI format
Options
Headers

Available since Camel 2.17.0

NATS is a fast and reliable messaging platform.

Maven users will need to add the following dependency to their pom.xml for this component.

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-nats</artifactId>
    <!-- use the same version as your Camel core version -->
    <version>x.y.z</version>
</dependency>

URI format

nats:servers[?options]

Where servers represents the list of NATS servers.

Options

The Nats component has no options.

The Nats component supports 18 endpoint options which are listed below:

{% raw %}

Name	Group	Default	Java Type	Description
servers	common		`String`	Required URLs to one or more NAT servers. Use comma to separate URLs when specifying multiple servers.
maxReconnectAttempts	common	`3`	`int`	Max reconnection attempts
noRandomizeServers	common	`false`	`boolean`	Whether or not randomizing the order of servers for the connection attempts
pedantic	common	`false`	`boolean`	Whether or not running in pedantic mode (this affects performace)
pingInterval	common	`4000`	`int`	Ping interval to be aware if connection is still alive (in milliseconds)
reconnect	common	`true`	`boolean`	Whether or not using reconnection feature
reconnectTimeWait	common	`2000`	`int`	Waiting time before attempts reconnection (in milliseconds)
ssl	common	`false`	`boolean`	Whether or not using SSL
topic	common		`String`	Required The name of topic we want to use
verbose	common	`false`	`boolean`	Whether or not running in verbose mode
bridgeErrorHandler	consumer	`false`	`boolean`	Allows for bridging the consumer to the Camel routing Error Handler which mean any exceptions occurred while the consumer is trying to pickup incoming messages or the likes will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions that will be logged at WARN/ERROR level and ignored.
maxMessages	consumer		`String`	Stop receiving messages from a topic we are subscribing to after maxMessages
poolSize	consumer	`10`	`int`	Consumer pool size
queueName	consumer		`String`	The Queue name if we are using nats for a queue configuration
exceptionHandler	consumer (advanced)		`ExceptionHandler`	To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this options is not in use. By default the consumer will deal with exceptions that will be logged at WARN/ERROR level and ignored.
exchangePattern	consumer (advanced)		`ExchangePattern`	Sets the exchange pattern when the consumer creates an exchange.
replySubject	producer		`String`	the subject to which subscribers should send response
synchronous	advanced	`false`	`boolean`	Sets whether synchronous processing should be strictly used or Camel is allowed to use asynchronous processing (if supported).

{% endraw %}

Headers

Name	Type	Description
CamelNatsMessageTimestamp	long	The timestamp of a consumed message.
CamelNatsSubscriptionId	Integer	The subscription ID of a consumer.

Producer example:

from("direct:send").to("nats://localhost:4222?topic=test");

Consumer example:

from("nats://localhost:4222?topic=test&maxMessages=5&queueName=test").to("mock:result");