In camel , Processor interface has the following api:
public interface Processor{
public void process(Exchange exchange) throws Exception;
}
In camel, is there any component that returns value similar to that given below:
public interface ComponentThatReturns<T>{
public T result(Exchange exchange) throws Exception;
}
Processors in Camel can store any needed values as either message headers or exchange properties.
If you had a component that returned a different type as you describe, something would still need to get that value into the Exchange to pass it to the next step in the route.
Related
I'm trying to setup a route that process files, here is my route configuration:
#Component
public class MyRoute extends RouteBuilder {
public static final String FIRST_ROUTE = "firstRoute";
public static final String SECOND_ROUTE = "secondRoute";
private final Processor myProcessor;
#Autowired
public MyRoute (#Qualifier("my.processor") Processor myProcessor) {
this.myProcessor= myProcessor;
}
#Override
public void configure() throws Exception {
from("file://{{data.input.dir}}?moveFailed=errors&delete=true&doneFileName=ACK-${file:name}&include=MY-FILE-FIRST.*")
.routeId(FIRST_ROUTE)
.process(myProcessor);
from("file://{{data.input.dir}}?moveFailed=errors&delete=true&doneFileName=ACK-${file:name}&include=MY-FILE-SECOND.*")
.routeId(SECOND_ROUTE)
.process(myProcessor);
}
}
As you can see I have two route for two files that have different name (one with FIRST, one with SECOND).
I want to trigger the process with variable to avoid to check the filename inside the process.
Currently my process function look like that:
public void process(Exchange exchange) throws Exception
What I want is something like that:
public void process(Exchange exchange, String identifier) throws Exception
And have the identifier set in the route definition (it's static, not depending on the filename, I need to have "FIRST" for the first route, and "SECOND" for the second one).
Is this possible ?
Because a process interface signature only takes an Exchange parameter, we cannot do process(Exchange exchange, String identifier).
Instead we can create a bean and call the method from the route like below.
from("file://{{data.input.dir}}?moveFailed=errors&delete=true&doneFileName=ACK-${file:name}&include=MY-FILE-SECOND.*")
.routeId(SECOND_ROUTE)
.bean(myBean,"process(*, " + SECOND + ")");
I have a Camel route which converts JSON to an object and passes it on to a processor class. Code is below. This ActiveMQ consumer is not acknowledging some messages, causing the topic to get backed up. The code does not explicitly set acknowledgement mode but a breakpoint shows these values -
acknowledgementMode = -1
acknowledgementModeName = null
What should be changed to ensure acknowledgements are sent on both successful processing and when an exception occurs inside the processor class?
#Component
public class MyRoute extends RouteBuilder {
private String mySubscription;
private MyProcessor myProcessor;
public MyRoute(#Value("${my.topic}") String tripSubscription, MyProcessor myProcessor) {
this.mySubscription = mySubscription;
this.myProcessor = myProcessor;
}
#Override
public void configure() {
from(mySubscription)
.unmarshal().json(JsonLibrary.Jackson, MyDTO.class)
.bean(myProcessor, "process(${body})")
.end();
}
}
The processor class -
#Slf4j
#Component
#AllArgsConstructor
public class MyProcessor {
public void process(MyDTO dto) {
//code that throws exception
}
}
The Camel JMS component docs at Github says that the default acknowledge mode is AUTO_ ACKNOWLEDGE.
However, the older docs at camel.apache.org says the default is -1 what corresponds to the value you see. Either the default was changed in a recent version or the new docs at Github are wrong.
The value -1 is somehow invalid because it is none of the defined modes.
Therefore you could give it a try to explicitly set acknowledgementModeName=AUTO_ACKNOWLEDGE on your consumer.
Side note… looks like you’re not setting “tripSubscription” into and instance variable if that was your intent…
I'm using camel-hystrix-eip in my project, I want a processor before my fallback, but it's not working
from("direct:sample").id("id:direct:sample").process(requestProcessor)
.hystrix()
.to(endPoint)
.onFallbackViaNetwork()
.to(fallback_endPoint)
I want to alter my fallback_endpoint using a processor, but seems like after onFallbackViaNetwork() we have to immediately provide to().
please suggest if there any way to do so.
I tried something like below, but it's not working.
from("direct:sample").id("id:direct:sample").process(requestProcessor)
.hystrix()
.to(endPoint)
.onFallbackViaNetwork()
.process(fallbackProcessor)
.to(fallback_endPoint)
Actually, I'm using requestProcessor to override the actual endpoint, and in case of a fallback, fallback_endPoint is also getting overridden, is there any way to avoid this.
You can have a processor after onFallbackViaNetwork(). You can also use the toD EIP to send the message to a dynamic endpoint.
Based on your code, you could set a Header MyEndpoint which contains your new endpoint string, and then reference it using .toD("${header.MyEndpoint}"). Repeat this pattern whenever you need to set a dynamic endpoint.
For example:
from("direct:sample")
.process(new Processor() {
#Override
public void process(Exchange exchange) throws Exception {
// do something
exchange.getIn().setHeader("EndpointHystrix", "mock:hystrix");
}
})
.hystrix()
.toD("${header.EndpointHystrix}")
.onFallbackViaNetwork()
.process(new Processor() {
#Override
public void process(Exchange exchange) throws Exception {
// do something more
exchange.getIn().setHeader("EndpointFallback", "mock:fallback");
}
})
.toD("${header.EndpointFallback}")
.end()
.to("...");
I've tested this in Camel 2.20.0 and 2.21.0.
It is possible to pass parameters to a Camel route?, for instance, in the next code snippet:
public class MyRoute extends RouteBuilder {
public void configure() throws Exception {
from("direct:start")
.to("cxf:bean:inventoryEndpoint?dataFormat=PAYLOAD");
}
}
The value for dataFormat is in hard code, but, what if I want set it dynamically?, passing a value from the code where route is called. I know this is possible adding a constructor and passing parameters in it, like this:
public class MyRoute extends RouteBuilder {
private String type;
public MyRoute(String type){
this.type = type;
}
public void configure() throws Exception {
from("direct:start")
.to("cxf:bean:inventoryEndpoint?dataFormat=" + type);
}
}
There is another way?
Thanks so much!
As you mentioned, you can use a constructor (or setters or any other Java/Framework instruments) if the parameters are static from a Camel point of view.
The parameters are configurable in the application, but after the application is started they do no more change. So, every message processed by the Camel route uses the same value.
In contrast, when the parameters are dynamic - i.e. they can change for every processed message, you can use the dynamic endpoint toD() of Camel. These endpoint addresses can contain expressions that are computed on runtime. For example the route
from("direct:start")
.toD("${header.foo}");
sends messages to a dynamic endpoint and takes the value from the message header named foo.
Or to use your example
.toD("cxf:bean:inventoryEndpoint?dataFormat=${header.dataFormat}");
This way you can set the dataformat for every message individually through a header.
You can find more about dynamic endpoints on this Camel documentation page
I am newcomer in Apache Camel. Please have a look to my code bellow:
I have a service which exposed as cxf webservice:
interface CxfService{
public OutputType hello(InputType input);
}
This is my route:
from("cxf:/test?serviceClass=" + CxfService.class.getName())
.to("log:cxfLog1")
.recipientList(simple("direct:${header.operationName}"));
from("direct:hello")
.process(new Processor(){
public void process(Exchange exchange) throws Exception {
InputType file = exchange.getIn().getBody(InputType.class);
exchange.getOut().setBody(new OutputType());
}
});
The code works as expected, it consume InputType and produce OutputType.
I want to borrow my body to do another stuffs, so i rewrite that like this:
from("cxf:/test?serviceClass=" + CxfService.class.getName())
.to("log:cxfLog1")
.recipientList(simple("direct:${header.operationName}"));
from("direct:hello")
.process(new Processor(){
public void process(Exchange exchange) throws Exception {
InputType file = exchange.getIn().getBody(InputType.class);
exchange.getOut().setHeader("header.temporary", new OutputType());
}
})
.to("some endpoint")
.setBody(simple("${header.temporary}"));
This webservice consume InputType and produce nothing. What wrong with that?
In your second piece of code, when setting the header.temporary, you should change two things:
setHeader("temporary", new OutputType()) - the 'header' prefix isn't
needed - you're addressing headers directly via the method call.
Use getIn() instead of getOut(). The input will get copied to the
output. You may want to do some research into the procedure for
Camel building the out message for details - I'm not 100% sure of
this one.
Change
exchange.getOut().setHeader("header.temporary", new OutputType());
To
exchange.getIn().setHeader("temporary"), new OutputType());
.setHeader() is when you use the simple language. In 99% of the cases getIn() is sufficient.