Available as of Camel version 2.16
The undertow component provides HTTP and WebSocket based endpoints for consuming and producing HTTP/WebSocket requests.
That is, the Undertow component behaves as a simple Web server. Undertow can also be used as a http client which mean you can also use it with Camel as a producer.
Tip
|
Since Camel version 2.21, the undertow component also supports WebSocket connections and can thus serve as a drop-in replacement for Camel websocket component or atmosphere-websocket 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-undertow</artifactId>
<version>x.x.x</version>
<!-- use the same version as your Camel core version -->
</dependency>
undertow:http://hostname[:port][/resourceUri][?options]
undertow:https://hostname[:port][/resourceUri][?options]
undertow:ws://hostname[:port][/resourceUri][?options]
undertow:wss://hostname[:port][/resourceUri][?options]
You can append query options to the URI in the following format,
?option=value&option=value&…
The Undertow component supports 5 options, which are listed below.
Name | Description | Default | Type |
---|---|---|---|
undertowHttpBinding (advanced) |
To use a custom HttpBinding to control the mapping between Camel message and HttpClient. |
UndertowHttpBinding |
|
sslContextParameters (security) |
To configure security using SSLContextParameters |
SSLContextParameters |
|
useGlobalSslContext Parameters (security) |
Enable usage of global SSL context parameters. |
false |
boolean |
hostOptions (advanced) |
To configure common options, such as thread pools |
UndertowHostOptions |
|
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 Undertow endpoint is configured using URI syntax:
undertow:httpURI
with the following path and query parameters:
Name | Description | Default | Type |
---|---|---|---|
httpURI |
Required The url of the HTTP endpoint to use. |
URI |
Name | Description | Default | Type |
---|---|---|---|
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 |
httpMethodRestrict (consumer) |
Used to only allow consuming if the HttpMethod matches, such as GET/POST/PUT etc. Multiple methods can be specified separated by comma. |
String |
|
matchOnUriPrefix (consumer) |
Whether or not the consumer should try to find a target consumer by matching the URI prefix if no exact match is found. |
false |
Boolean |
optionsEnabled (consumer) |
Specifies whether to enable HTTP OPTIONS for this Servlet consumer. By default OPTIONS is turned off. |
false |
boolean |
exceptionHandler (consumer) |
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 or ERROR level and ignored. |
ExceptionHandler |
|
exchangePattern (consumer) |
Sets the exchange pattern when the consumer creates an exchange. |
ExchangePattern |
|
cookieHandler (producer) |
Configure a cookie handler to maintain a HTTP session |
CookieHandler |
|
keepAlive (producer) |
Setting to ensure socket is not closed due to inactivity |
true |
Boolean |
options (producer) |
Sets additional channel options. The options that can be used are defined in org.xnio.Options. To configure from endpoint uri, then prefix each option with option., such as option.close-abort=true&option.send-buffer=8192 |
Map |
|
reuseAddresses (producer) |
Setting to facilitate socket multiplexing |
true |
Boolean |
tcpNoDelay (producer) |
Setting to improve TCP protocol performance |
true |
Boolean |
throwExceptionOnFailure (producer) |
Option to disable throwing the HttpOperationFailedException in case of failed responses from the remote server. This allows you to get all responses regardless of the HTTP status code. |
true |
Boolean |
transferException (producer) |
If enabled and an Exchange failed processing on the consumer side and if the caused Exception was send back serialized in the response as a application/x-java-serialized-object content type. On the producer side the exception will be deserialized and thrown as is instead of the HttpOperationFailedException. The caused exception is required to be serialized. This is by default turned off. If you enable this then be aware that Java will deserialize the incoming data from the request to Java and that can be a potential security risk. |
false |
Boolean |
headerFilterStrategy (advanced) |
To use a custom HeaderFilterStrategy to filter header to and from Camel message. |
HeaderFilterStrategy |
|
synchronous (advanced) |
Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported). |
false |
boolean |
undertowHttpBinding (advanced) |
To use a custom UndertowHttpBinding to control the mapping between Camel message and undertow. |
UndertowHttpBinding |
|
fireWebSocketChannelEvents (websocket) |
if true, the consumer will post notifications to the route when a new WebSocket peer connects, disconnects, etc. See UndertowConstants.EVENT_TYPE and EventType. |
false |
boolean |
sendTimeout (websocket) |
Timeout in milliseconds when sending to a websocket channel. The default timeout is 30000 (30 seconds). |
30000 |
Integer |
sendToAll (websocket) |
To send to all websocket subscribers. Can be used to configure on endpoint level, instead of having to use the UndertowConstants.SEND_TO_ALL header on the message. |
Boolean |
|
useStreaming (websocket) |
if true, text and binary messages coming through a WebSocket will be wrapped as java.io.Reader and java.io.InputStream respectively before they are passed to an Exchange; otherwise they will be passed as String and byte respectively. |
false |
boolean |
sslContextParameters (security) |
To configure security using SSLContextParameters |
SSLContextParameters |
Camel uses the same message headers as the HTTP
component.
From Camel 2.2, it also uses
Exchange.HTTP_CHUNKED,CamelHttpChunked
header to turn on or turn off
the chuched encoding on the camel-undertow consumer.
Camel also populates all request.parameter and request.headers. For
example, given a client request with the URL,
http://myserver/myserver?orderid=123
, the exchange will contain a
header named orderid
with the value 123.
The following is a basic example of how to send an HTTP request to an existing HTTP endpoint.
in Java DSL
from("direct:start")
.to("undertow:http://www.google.com");
or in XML
<route>
<from uri="direct:start"/>
<to uri="undertow:http://www.google.com"/>
<route>
In this sample we define a route that exposes a HTTP service at
http://localhost:8080/myapp/myservice
:
<route>
<from uri="undertow:http://localhost:8080/myapp/myservice"/>
<to uri="bean:myBean"/>
</route>
In this sample we define a route that exposes a WebSocket service at
http://localhost:8080/myapp/mysocket
and returns back a response to the same channel:
<route>
<from uri="undertow:ws://localhost:8080/myapp/mysocket"/>
<transform><simple>Echo ${body}</simple></transform>
<to uri="undertow:ws://localhost:8080/myapp/mysocket"/>
</route>
When you specify localhost
in a URL, Camel exposes the endpoint only
on the local TCP/IP network interface, so it cannot be accessed from
outside the machine it operates on.
If you need to expose a Jetty endpoint on a specific network interface,
the numerical IP address of this interface should be used as the host.
If you need to expose a Jetty endpoint on all network interfaces, the
0.0.0.0
address should be used.
To listen across an entire URI prefix, see How do I let Jetty match wildcards.
If you actually want to expose routes by HTTP and already have a Servlet, you should instead refer to the Servlet Transport.