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Comment: Migration of unmigrated content due to installation of a new plugin

Cometd Component

The cometd: component is a transport for working with the jetty implementation of the cometd/bayeux protocol.
Using this component in combination with the dojo toolkit library it's possible to push Camel messages directly into the browser using an AJAX based mechanism.

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

Code Block
xml
xml
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-cometd</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

Code Block
cometd://host:port/channelName[?options]

The channelName represents a topic that can be subscribed to by the Camel endpoints.

Examples

No Format
cometd://localhost:8080/service/mychannel
cometds://localhost:8443/service/mychannel

where cometds: represents an SSL configured endpoint.

See this blog entry by David Greco who contributed this component to Apache Camel, for a full sample.

Options

Wiki Markup
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|| Name || Default Value || Description ||
| {{resourceBase}} | | The root directory for the web resources or classpath. Use the protocol file: or classpath: depending if you want that the component loads the resource from file system or classpath. Classpath is required for OSGI deployment where the resources are packaged in the jar. Notice this option has been renamed to {{baseResource}} from *Camel 2.7* onwards. |
| {{baseResource}} | | *Camel 2.7:* The root directory for the web resources or classpath. Use the protocol file: or classpath: depending if you want that the component loads the resource from file system or classpath. Classpath is required for OSGI deployment where the resources are packaged in the jar |
| {{timeout}} | {{240000}} | The server side poll timeout in milliseconds. This is how long the server will hold a reconnect request before responding. |
| {{interval}} | {{0}} | The client side poll timeout in milliseconds. How long a client will wait between reconnects |
| {{maxInterval}} | {{30000}} | The max client side poll timeout in milliseconds. A client will be removed if a connection is not received in this time. |
| {{multiFrameInterval}} | {{1500}} | The client side poll timeout, if multiple connections are detected from the same browser. |
| {{jsonCommented}} | {{true}} | If {{true}}, the server will accept JSON wrapped in a comment and will generate JSON wrapped in a comment. This is a defence against Ajax Hijacking. |
| {{logLevel}} | {{1}} | {{0}}=none, {{1}}=info, {{2}}=debug. |
| sslContextParameters | | *Camel 2.9:* Reference to a {{org.apache.camel.util.jsse.SSLContextParameters}} in the [Registry|http://camel.apache.org/registry.html].&nbsp; This reference overrides any configured SSLContextParameters at the component level.&nbsp; See [Using the JSSE Configuration Utility|CAMEL:Camel Configuration Utilities]. \\ |
| {{crossOriginFilterOn}} | {{false}} | *Camel 2.10:* If {{true}}, the server will support for cross-domain filtering |
| {{allowedOrigins}} | {{*}} | *Camel 2.10:* The origins domain that support to cross, if the {{crosssOriginFilterOn}} is {{true}} |
| {{filterPath}} | | *Camel 2.10:* The filterPath will be used by the CrossOriginFilter, if the {{crosssOriginFilterOn}} is {{true}} |
| {{disconnectLocalSession}} | {{true}} | *Camel 2.10.5/2.11.1: (Producer only)*: Whether to disconnect local sessions after publishing a message to its channel. Disconnecting local session is needed as they are not swept by default by CometD, and therefore you can run out of memory.  |

{div}

You can append query options to the URI in the following format, ?option=value&option=value&...

Here is some examples on How to pass the parameters

For file (for webapp resources located in the Web Application directory --> cometd://localhost:8080?resourceBase=file./webapp
For classpath (when by example the web resources are packaged inside the webapp folder --> cometd://localhost:8080?resourceBase=classpath:webapp

Authentication

Available as of Camel 2.8

You can configure custom SecurityPolicy and Extension's to the CometdComponent which allows you to use authentication as documented here

Setting up SSL for Cometd Component

Using the JSSE Configuration Utility

As of Camel 2.9, the Cometd component supports SSL/TLS configuration through the Camel JSSE Configuration Utility.  This utility greatly decreases the amount of component specific code you need to write and is configurable at the endpoint and component levels.  The following examples demonstrate how to use the utility with the Cometd component.

Programmatic configuration of the component
Code Block
KeyStoreParameters ksp = new KeyStoreParameters();
ksp.setResource("/users/home/server/keystore.jks");
ksp.setPassword("keystorePassword");

KeyManagersParameters kmp = new KeyManagersParameters();
kmp.setKeyStore(ksp);
kmp.setKeyPassword("keyPassword");

TrustManagersParameters tmp = new TrustManagersParameters();
tmp.setKeyStore(ksp);

SSLContextParameters scp = new SSLContextParameters();
scp.setKeyManagers(kmp);
scp.setTrustManagers(tmp);

CometdComponent commetdComponent = getContext().getComponent("cometds", CometdComponent.class);
commetdComponent.setSslContextParameters(scp);
Spring DSL based configuration of endpoint
Code Block
xml
xml
...
  <camel:sslContextParameters
      id="sslContextParameters">
    <camel:keyManagers
        keyPassword="keyPassword">
      <camel:keyStore
          resource="/users/home/server/keystore.jks"
          password="keystorePassword"/>
    </camel:keyManagers>
    <camel:trustManagers>
      <camel:keyStore
          resource="/users/home/server/keystore.jks"
          password="keystorePassword"/>
    </camel:keyManagers>
  </camel:sslContextParameters>...
...
  <to uri="cometds://127.0.0.1:443/service/test?baseResource=file:./target/test-classes/webapp&timeout=240000&interval=0&maxInterval=30000&multiFrameInterval=1500&jsonCommented=true&logLevel=2&sslContextParameters=#sslContextParameters"/>...
Include Page
Endpoint See Also
Endpoint See Also