The http: component provides HTTP based endpoints for consuming external HTTP resources (as a client to call external servers using HTTP).
Will by default use port 80 for HTTP and 443 for HTTPS.
You can append query options to the URI in the following format, ?option=value&option=value&...
|camel-http vs camel-jetty|
You can only produce to endpoints generated by the HTTP component. Therefore it should never be used as input into your camel Routes. To bind/expose an HTTP endpoint via a HTTP server as input to a camel route, you can use the Jetty Component
|throwExceptionOnFailure||true||Camel 2.0: Option to disable throwing the HttpOperationFailedException in case of failed responses from the remote server. This allows you to get all responses regardles of the HTTP status code.|
|bridgeEndpoint||false||Camel 2.1: If the option is true , HttpProducer will ignore the Exchange.HTTP_URI header, and use the endpoint's URI for request. You may also set the throwExcpetionOnFailure to be false to let the HttpProducer send all the fault response back.|
|httpBindingRef||null||Reference to a org.apache.camel.component.http.HttpBinding in the Registry.|
|username||null||Username for Basic HTTP/NTML Authentication.|
|password||null||Password for Basic HTTP/NTML Authentication.|
|domain||null||Camel 2.1: Domain for NTML Authentication. This option must be used to force NTML authentication.|
|proxyHost||null||The proxy host name * only for >= Camel 1.6.2 *.|
|proxyPort||null||The proxy port number * only for >= Camel 1.6.2 *.|
|proxyUsername||null||Username for proxy authentication * only for >= Camel 1.6.2 *.|
|proxyPassword||null||Password for proxy authentication * only for >= Camel 1.6.2 *.|
|httpClientConfigurerRef||null||Reference to a org.apache.camel.component.http.HttpClientConfigurer in the Registry.|
|httpClient.XXX||null||Setting options on the HttpClientParams. For instance httpClient.soTimeout=5000 will set the SO_TIMEOUT to 5 seconds.|
|HttpProducer.HTTP_URI||String||Camel 1.5.1: URI to call. Will override existing URI set directly on the endpoint. Is set on the In message.|
|HttpProducer.HTTP_RESPONSE_CODE||int||The HTTP response code from the external server. Is 200 for OK. Is set on the Out message.|
|HttpProducer.QUERY||String||URI parameters. Will override existing URI parameters set directly on the endpoint. Is set on the In message.|
|Exchange.HTTP_URI||String||URI to call. Will override existing URI set directly on the endpoint.|
|Exchange.HTTP_PATH||String||Request URI's path.|
|Exchange.HTTP_QUERY||String||URI parameters. Will override existing URI parameters set directly on the endpoint.|
|Exchange.HTTP_RESPONSE_CODE||int||The HTTP response code from the external server. Is 200 for OK.|
|Exchange.CONTENT_TYPE||String||The HTTP content type. Is set on both the IN and OUT message to provide a content type, such as text/html.|
|Exchange.CONTENT_ENCODING||String||The HTTP content encoding. Is set on both the IN and OUT message to provide a content encoding, such as gzip.|
Camel will store the HTTP response from the external server on the OUT body. All headers from the IN message will be copied to the OUT message, so headers are preserved during routing. Additionally Camel will add the HTTP response headers as well to the OUT message headers.
Camel will handle according to the HTTP response code:
The option, throwExceptionOnFailure, can be set to false to prevent the HttpOperationFailedException from being thrown for failed response codes. This allows you to get any response from the remote server.
This exception contains the following information:
In Camel 1.5 the following algorithm is used to determine if either GET or POST HTTP method should be used:
1. Use method provided in header.
2. GET if query string is provided in header.
3. GET if endpoint is configured with a query string.
4. POST if there is data to send (body is not null).
5. GET otherwise.
Available as of Camel 2.0
You can get access to these two using the Camel type converter system using
Or you can get access to them from HttpMessage directly using a type cast:
You can set the HTTP producer's URI directly form the endpoint URI. In the route below, Camel will call out to the external server, oldhost, using HTTP.
And the equivalent Spring sample:
In Camel 1.5.1 you can override the HTTP endpoint URI by adding a header with the key, HttpProducer.HTTP_URI, on the message.
And the same code in Camel 2.0:
Where Constants is the class, org.apache.camel.component.http.Constants.
The http producer supports URI parameters to be sent to the HTTP server. The URI parameters can either be set directly on the endpoint URI or as a header with the key HttpProducer.QUERY on the message.
Or options provided in a header:
The HTTP component provides a way to set the HTTP request method by setting the message header. Here is an example;
The method can be written a bit shorter using the string constants:
And the equivalent Spring sample:
See the unit test in this link
Only for >= Camel 1.6.2
The HTTP component provides a way to configure a proxy.
There is also support for proxy authentication via the proxyUsername and proxyPassword options.
Only for >= Camel 1.6.2
The HTTP component will detect Java System Properties for http.proxyHost and http.proxyPort and use them if provided.
See more at SUN http proxy documentation.
Camel will first set the settings from Java System Properties and then the endpoint proxy options if provided.
So you can override the system properties with the endpoint options.
If you are using POST to send data you can configure the charset using the Exchange property:
Or the httpClient options: httpClient.contentCharset=iso-8859-1
The sample polls the Google homepage every 10 seconds and write the page to the file message.html:
In this sample we have the complete URI endpoint that is just what you would have typed in a web browser. Multiple URI parameters can of course be set using the & character as separator, just as you would in the web browser. Camel does no tricks here.
In the header value above notice that it should not be prefixed with ? and you can separate parameters as usual with the & char.
You can get the HTTP response code from the HTTP component by getting the value from the Out message header with HttpProducer.HTTP_RESPONSE_CODE.
Available as of Camel 2.0
In the route below we want to route a message that we enrich with data returned from a remote HTTP call. As we want any response from the remote server, we set the throwExceptionOnFailure option to false so we get any response in the AggregationStrategy. As the code is based on a unit test that simulates a HTTP status code 404, there is some assertion code etc.
To disable cookies you can set the HTTP Client to ignore cookies by adding this URI option:
If you need more control over the HTTP producer you should use the HttpComponent where you can set various classes to give you custom behavior.
The HTTP Component has a org.apache.commons.httpclient.HttpConnectionManager where you can configure various global configuration for the given component.
By global, we mean that any endpoint the component creates has the same shared HttpConnectionManager. So, if we want to set a different value for the max connection per host, we need to define it on the HTTP component and not on the endpoint URI that we usually use. So here comes:
First, we define the http component in Spring XML. Yes, we use the same scheme name, http, because otherwise Camel will auto-discover and create the component with default settings. What we need is to overrule this so we can set our options. In the sample below we set the max connection to 5 instead of the default of 2.
And then we can just use it as we normally do in our routes:
An end user reported that he had problem with authenticating with HTTPS. The problem was eventually resolved when he discovered the HTTPS server did not return a HTTP code 401 Authorization Required. The solution was to set the following URI option: httpClient.authenticationPreemptive=true
See this link from a mailing list discussion with some code to outline how to do this with the Apache Commons HTTP API.
Basically camel-http component is built on the top of Apache HTTP client, and you can implement a custom org.apache.camel.component.http.HttpClientConfigurer to do some configuration on the http client if you need full control of it.
However if you just want to specify the keystore and truststore you can do this with Apache HTTP HttpClientConfigurer, for example:
And then you need to create a class that implements HttpClientConfigurer, and registers https protocol providing a keystore or truststore per example above. Then, from your camel route builder class you can hook it up like so: