Start with Apache Camel - spring

Question

I’m very new to Apache Camel and will very appreciate if someone could provide me what camel components may be used to solve particular task.
I have a simple REST WS. This service is not accessible to audience.
The idea is to build middle layer between user requests and endpoint service.
So I will have to catch user’s request, make some manipulations with it, send to restricted WS and give a response to user.
I’m just started learning apache camel and the question is what is the best way to implement this logic.
Thx in advance!

Answer 1

Frankly, Camel is not the right framework to implement web controllers. Of course there is the Camel Rest Module, but it is stretching the responsibilities of the framework too far.
I recommend using a more adapt framework for the implementation of the WS, e.g. Spring or Jersey, and call Camel endpoints programmatically from the request handlers. Within Spring, triggering Camel Endpoints is easy since the CamelContext can get autowired into your web controller:
camelContext.createProducerTemplate().sendBodyAndHeader("direct:myEndpoint", null, "id", id);
For your Camel Root this approach means, that it starts of with a Direct endpoint, then forwards to a Camel http endpoint and if necessary forwards the output from the HTTP call to some Spring bean transformation step, before finally passing it back to the web controller handler method:
<route>
<from uri="direct:myEndpoint"/>
<to uri="http:somehost.com"/>
<transform>
<method ref="springBean" method="doSomeTransformation"/>
</transform>
</route>

Answer 2

Well there are several camel components you can use for this task. Think of Camel as a toolbox where you can choose from several tools for the same task.
You can use:
Camel-HTTP4 http://camel.apache.org/http4.html
Camel-Jetty http://camel.apache.org/jetty.html
Camel-Restlet http://camel.apache.org/restlet.html
Camel-CXFRS http://camel.apache.org/cxfrs.html
Example using java dsl:
from("jetty://http://localhost:7070/test").to("jetty://http://localhost:7070/test1");
Example using blueprint
<route>
<from uri="jetty://http://localhost:7070/test"/>
<to uri="jetty://http://localhost:7070/test1"/>
<route>