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From "Claus Ibsen">
Subject RE: from http://... to file://...
Date Tue, 24 Jun 2008 08:00:43 GMT
Hi Joe,

Yes its a correct sequence. However the seda queue divides the exchange into two processes
that are async. It depends on your requirements. With the seda queue you can respond immediately
to the client that you got the data. However as you haven't processed the data you don't know
if its valid data that you can process.

Without the seda queue you can process and validate the data before sending a response back
to the client. You can change the seda queaue to a direct queue that is synchronous and thus
the response to the client is only sent after the exchange has been written to file.

If you wish to do much more complex processing your can use a .process(new MyComplexProcessor())
where you can do all the java complex processing you want. In fact in Camel there are many
ways to heaven - you can also use the bean to instruct Camel to use a POJO.

>From the MyComplexProcessor you can extract the in, transform, and fetch the endpoint
for the persistent queue and send it there. You can inject a ProducerTemplate, or a Endpoint
using annotations etc. But for start you can just get the camel context where you can get
the persistent queue endpoint where you can create a exchange and a producer to send the exchange.

For example: see the spring-jms tutorial:

Med venlig hilsen
Claus Ibsen
Skovsgårdsvænget 21
8362 Hørning
Tlf. +45 2962 7576
-----Original Message-----
From: Joe Satch [] 
Sent: 23. juni 2008 18:56
Subject: RE: from http://... to file://...

Hi Claus,

Thanks for the reply!

Yeah, it worked. I am still thinking abt the correct sequence here. Is this
a correct sequence:
1. Jetty gets an Inout MEP
2. A copy of exchange goes to the seda and out content in the original
exchange is set to ("We got your request")
3. MyJettyProcessor picks it up from the SEDA and wirtes to the fille.

Also, if I wish to do more complex processing with the message after it
comes out from jetty, this is what i tried to do, but i got stuck at one
I coded a POJO which which was the target of jetty component. I wanted to
grab the inout mep, make its out content as "recieved", extract the "in"
payload, transform it into something, create an inonly MEP and write it to a
persistent queue. The problem is that I am not able to figure out how to
return the Inout exchange back to the jetty component and then
simultaneously persist the Inonly MEP to the JMS queue. 


Claus Ibsen wrote:
> Hi Joe
> By all means please post any questions you have to this user forum. 
> Ad 1)
> Yes your observations is correct. If the file component gets an out
> capable exchange then its trying to poll the file. So you need to change
> the mep pattern to inonly.
> The HTTP protocol is by nature request-response based so that is why Camel
> will send back a response if you use camel-jetty. You should probably send
> back a response with HTTP STATUS 200 to indicate to the client that you
> have accepted/consume his request.
> Ad 2)
> Send a response back to the client.
> Ad 3)
> You can use a processor to change/handle the exchange programmatically.
> from("xxx").process(new MyProcessor()).to("yyy")
> Here is some help for your route to do what you want:
>     protected RouteBuilder createRouteBuilder() throws Exception {
>         return new RouteBuilder() {
>             public void configure() throws Exception {
> from("jetty:http://localhost:8080/myworld").to("seda:in").setBody(constant("We
> got your request"));
>                 from("seda:in").process(new MyJettyProcessor()).
>                     setHeader(FileComponent.HEADER_FILE_NAME,
> "hello.txt").to("file://target/myworld");
>             }
>         };
>     }
>     private class MyJettyProcessor implements Processor {
>         public void process(Exchange exchange) throws Exception {
>             // must convert to in only as file producer will try to load
> the file if the exchange pattner
>             // is out capable.
>             exchange.setPattern(ExchangePattern.InOnly);
>         }
>     }
> Med venlig hilsen
> Claus Ibsen
> ......................................
> Silverbullet
> Skovsgårdsvænget 21
> 8362 Hørning
> Tlf. +45 2962 7576
> Web:
> -----Original Message-----
> From: Joe Satch [] 
> Sent: 22. juni 2008 22:18
> To:
> Subject: RE: from http://... to file://...
> Hi,
> I am quite new to camel, so plz excuse me if i say something fundamentally
> wrong. 
> What i am not able to understand here is that if I wish to open an http
> serversocket to listen to requests and persist them to a file, how do i go
> for it. I could open a serversocket using jetty component, and then I
> routed
> the incoming messages to a file URI. It threw me exception.
> My analysis of the problem was that the jetty server component makes an
> Inout exchange and forwards the content to file URI and waits for the
> response to come as it instantiated an Inout MEP. And it never gets the
> response back as the file component probably expects an Inonly MEP or
> something of that sort. 
> My questions
> 1. Is my analysis wrong.
> 2. If I wish to do what i am trying to, how do I go abt it ?
> 3. How do I trap an exchange programtically and then do something with it
> ?
> thanks
>>Ah the issue is that the Jetty component is an EventDrivenConsumer and not
> Scheduled. So you have to >trigger the event yourself to start the event
> in
> jetty.
> "message.txt").to("file:target/hello");
>>This will invoke the google homepage every 10th second and store it as a
> file.
> -- 
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