Chapter 368. Jetty Websocket Component Available as of Camel version 2.10 The websocket component provides websocket endpoints for communicating with clients using websocket. The component uses Eclipse Jetty Server which implements the IETF specification (drafts and RFC 6455). It supports the protocols ws:// and wss://. To use wss:// protocol, the SSLContextParameters must be defined. Version currently supported Camel 2.18 uses Jetty 9 368.1. URI format websocket://hostname[:port][/resourceUri][?options] You can append query options to the URI in the following format, ?option=value&option=value&... 368.2. Websocket Options The Jetty Websocket component supports 14 options, which are listed below. Name Description Default Type staticResources (consumer) Set a resource path for static resources (such as .html files etc). The resources can be loaded from classpath, if you prefix with classpath:, otherwise the resources is loaded from file system or from JAR files. For example to load from root classpath use classpath:., or classpath:WEB-INF/static If not configured (eg null) then no static resource is in use. String host (common) The hostname. The default value is 0.0.0.0 0.0.0.0 String port (common) The port number. The default value is 9292 9292 Integer sslKeyPassword (security) The password for the keystore when using SSL. String sslPassword (security) The password when using SSL. String sslKeystore (security) The path to the keystore. String enableJmx (advanced) If this option is true, Jetty JMX support will be enabled for this endpoint. See Jetty JMX support for more details. false boolean minThreads (advanced) To set a value for minimum number of threads in server thread pool. MaxThreads/minThreads or threadPool fields are required due to switch to Jetty9. The default values for minThreads is 1. Integer maxThreads (advanced) To set a value for maximum number of threads in server thread pool. MaxThreads/minThreads or threadPool fields are required due to switch to Jetty9. The default values for maxThreads is 1 2 noCores. Integer threadPool (advanced) To use a custom thread pool for the server. MaxThreads/minThreads or threadPool fields are required due to switch to Jetty9. ThreadPool sslContextParameters (security) To configure security using SSLContextParameters SSLContextParameters useGlobalSslContext Parameters (security) Enable usage of global SSL context parameters. false boolean socketFactory (common) To configure a map which contains custom WebSocketFactory for sub protocols. The key in the map is the sub protocol. The default key is reserved for the default implementation. Map resolveProperty Placeholders (advanced) Whether the component should resolve property placeholders on itself when starting. Only properties which are of String type can use property placeholders. true boolean The Jetty Websocket endpoint is configured using URI syntax: with the following path and query parameters: 368.2.1. Path Parameters (3 parameters): Name Description Default Type host The hostname. The default value is 0.0.0.0. Setting this option on the component will use the component configured value as default. 0.0.0.0 String port The port number. The default value is 9292. Setting this option on the component will use the component configured value as default. 9292 Integer resourceUri Required Name of the websocket channel to use String 368.2.2. Query Parameters (18 parameters): Name Description Default Type maxBinaryMessageSize (common) Can be used to set the size in bytes that the websocket created by the websocketServlet may be accept before closing. (Default is -1 - or unlimited) -1 Integer bridgeErrorHandler (consumer) 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 or ERROR level and ignored. false boolean sessionSupport (consumer) Whether to enable session support which enables HttpSession for each http request. false boolean staticResources (consumer) Set a resource path for static resources (such as .html files etc). The resources can be loaded from classpath, if you prefix with classpath:, otherwise the resources is loaded from file system or from JAR files. For example to load from root classpath use classpath:., or classpath:WEB-INF/static If not configured (eg null) then no static resource is in use. String exceptionHandler (consumer) To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this option is not in use. By default the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored. ExceptionHandler exchangePattern (consumer) Sets the exchange pattern when the consumer creates an exchange. ExchangePattern sendTimeout (producer) Timeout in millis when sending to a websocket channel. The default timeout is 30000 (30 seconds). 30000 Integer sendToAll (producer) To send to all websocket subscribers. Can be used to configure on endpoint level, instead of having to use the WebsocketConstants.SEND_TO_ALL header on the message. Boolean bufferSize (advanced) Set the buffer size of the websocketServlet, which is also the max frame byte size (default 8192) 8192 Integer maxIdleTime (advanced) Set the time in ms that the websocket created by the websocketServlet may be idle before closing. (default is 300000) 300000 Integer maxTextMessageSize (advanced) Can be used to set the size in characters that the websocket created by the websocketServlet may be accept before closing. Integer minVersion (advanced) Can be used to set the minimum protocol version accepted for the websocketServlet. (Default 13 - the RFC6455 version) 13 Integer synchronous (advanced) Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported). false boolean allowedOrigins (cors) The CORS allowed origins. Use to allow all. String crossOriginFilterOn (cors) Whether to enable CORS false boolean filterPath (cors) Context path for filtering CORS String enableJmx (monitoring) If this option is true, Jetty JMX support will be enabled for this endpoint. See Jetty JMX support for more details. false boolean sslContextParameters (security) To configure security using SSLContextParameters SSLContextParameters 368.3. Spring Boot Auto-Configuration The component supports 15 options, which are listed below. Name Description Default Type camel.component.websocket.enable-jmx If this option is true, Jetty JMX support will be enabled for this endpoint. See Jetty JMX support for more details. false Boolean camel.component.websocket.enabled Enable websocket component true Boolean camel.component.websocket.host The hostname. The default value is 0.0.0.0 0.0.0.0 String camel.component.websocket.max-threads To set a value for maximum number of threads in server thread pool. MaxThreads/minThreads or threadPool fields are required due to switch to Jetty9. The default values for maxThreads is 1 2 noCores. Integer camel.component.websocket.min-threads To set a value for minimum number of threads in server thread pool. MaxThreads/minThreads or threadPool fields are required due to switch to Jetty9. The default values for minThreads is 1. Integer camel.component.websocket.port The port number. The default value is 9292 9292 Integer camel.component.websocket.resolve-property-placeholders Whether the component should resolve property placeholders on itself when starting. Only properties which are of String type can use property placeholders. true Boolean camel.component.websocket.socket-factory To configure a map which contains custom WebSocketFactory for sub protocols. The key in the map is the sub protocol. The default key is reserved for the default implementation. Map camel.component.websocket.ssl-context-parameters To configure security using SSLContextParameters. The option is a org.apache.camel.util.jsse.SSLContextParameters type. String camel.component.websocket.ssl-key-password The password for the keystore when using SSL. String camel.component.websocket.ssl-keystore The path to the keystore. String camel.component.websocket.ssl-password The password when using SSL. String camel.component.websocket.static-resources Set a resource path for static resources (such as .html files etc). The resources can be loaded from classpath, if you prefix with classpath:, otherwise the resources is loaded from file system or from JAR files. For example to load from root classpath use classpath:., or classpath:WEB-INF/static If not configured (eg null) then no static resource is in use. String camel.component.websocket.thread-pool To use a custom thread pool for the server. MaxThreads/minThreads or threadPool fields are required due to switch to Jetty9. The option is a org.eclipse.jetty.util.thread.ThreadPool type. String camel.component.websocket.use-global-ssl-context-parameters Enable usage of global SSL context parameters. false Boolean 368.4. Message Headers The websocket component uses 2 headers to indicate to either send messages back to a single/current client, or to all clients. WebsocketConstants.SEND_TO_ALL Sends the message to all clients which are currently connected. You can use the sendToAll option on the endpoint instead of using this header. WebsocketConstants.CONNECTION_KEY Sends the message to the client with the given connection key. WebsocketConstants.REMOTE_ADDRESS Remote address of the websocket session. 368.5. Usage In this example we let Camel exposes a websocket server which clients can communicate with. The websocket server uses the default host and port, which would be 0.0.0.0:9292 . The example will send back an echo of the input. To send back a message, we need to send the transformed message to the same endpoint "websocket://echo" . This is needed because by default the messaging is InOnly. This example is part of an unit test, which you can find here . As a client we use the AHC library which offers support for web socket as well. Here is another example where webapp resources location have been defined to allow the Jetty Application Server to not only register the WebSocket servlet but also to expose web resources for the browser. Resources should be defined under the webapp directory. from("activemq:topic:newsTopic") .routeId("fromJMStoWebSocket") .to("websocket://localhost:8443/newsTopic?sendToAll=true&staticResources=classpath:webapp"); 368.6. Setting up SSL for WebSocket Component 368.6.1. Using the JSSE Configuration Utility As of Camel 2.10, the WebSocket 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 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 ... <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:trustManagers> </camel:sslContextParameters>... ... <to uri="websocket://127.0.0.1:8443/test?sslContextParameters=#sslContextParameters"/>... Java DSL based configuration of endpoint ... protected RouteBuilder createRouteBuilder() throws Exception { return new RouteBuilder() { public void configure() { String uri = "websocket://127.0.0.1:8443/test?sslContextParameters=#sslContextParameters"; from(uri) .log(">>> Message received from WebSocket Client : USD{body}") .to("mock:client") .loop(10) .setBody().constant(">> Welcome on board!") .to(uri); ... 368.7. See Also Configuring Camel Component Endpoint Getting Started AHC Jetty Twitter Websocket Example demonstrates how to poll a constant feed of twitter searches and publish results in real time using web socket to a web page.

Commands:
websocket://hostname[:port][/resourceUri][?options]
websocket:host:port/resourceUri
from("activemq:topic:newsTopic") .routeId("fromJMStoWebSocket") .to("websocket://localhost:8443/newsTopic?sendToAll=true&staticResources=classpath:webapp");
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);
<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:trustManagers> </camel:sslContextParameters> <to uri="websocket://127.0.0.1:8443/test?sslContextParameters=#sslContextParameters"/>
protected RouteBuilder createRouteBuilder() throws Exception { return new RouteBuilder() { public void configure() { String uri = "websocket://127.0.0.1:8443/test?sslContextParameters=#sslContextParameters"; from(uri) .log(">>> Message received from WebSocket Client : USD{body}") .to("mock:client") .loop(10) .setBody().constant(">> Welcome on board!") .to(uri);