spring-integration end point

Question

First post. I'm new to Spring Integration and have the following scenario: I have a service, "xyzSearchService.getXYZ", that is invoked as a result of an http inbound request. It does some logic then calls the "routingChannel" which in turn calls the google geocode service.

I want the response from google to be returned to xyzSearchService.getXYZ but I am not sure how to configure the replyChannel in the "outboundGateway". Now I have it go to another method in the same service where I can see the results but I want it to be returned to the service/method that called it. Not sure how to configure my final outbound-channel-adapter?

   <int-http:inbound-gateway id="inboundXYZSearchRequestGateway"
                              supported-methods="GET, POST"
                              request-channel="xyzSearchRequest"
                              reply-channel="xyzSearchResponse"
                              mapped-response-headers="Return-Status, Return-Status-Msg, HTTP_RESPONSE_HEADERS"
                              view-name="/xyz"
                              path="/services/xyz/zip/{zipcode}/search"
                              reply-timeout="50000">

        <int-http:header name="zipcode" expression="#pathVariables.zipcode"/>
    </int-http:inbound-gateway>

    <int:service-activator id="xyzServiceActivator"
                           input-channel="xyzSearchRequest"
                           output-channel="xyzSearchResponse"
                           ref="xyzSearchService"
                           method="getXYZ"
                           requires-reply="true"
                           send-timeout="60000"/>

//the service activator method does some logic and invokes the "routingChannel"

    <int:chain input-channel="routingChannel">
        <int:router  
                    expression="payload.serviceType"  
                    default-output-channel="channel_default"  
                    resolution-required="false">
        </int:router>
    </int:chain>

    <int-http:outbound-gateway  id="outboundGateway"
                                url="http://maps.googleapis.com/maps/api/geocode/json?address={zipCode}"
                                http-method="GET"
                                request-factory="requestFactory"
                                request-channel="restchannel"
                                reply-channel="channel2"
                                expected-response-type="java.lang.String">
        <int-http:uri-variable name="zipCode" `enter code `enter code here`here`expression="payload.data['zipcode']"/>
    </int-http:outbound-gateway>


    <int:channel id="channel2"/>
    <int:outbound-channel-adapter channel="channel2" ref="xyzSearchService" method="routeUnit" />

EDIT:

Are you suggesting I create an inbound-gateway, as follows, and invoke that from my service method?

<int-http:inbound-gateway id="inboundNewZipRequestGateway"
                          supported-methods="GET, POST"
                          request-channel="zipRoutingChannel"
                          reply-channel="zipSearchResponse"
                          mapped-response-headers="Return-Status, Return-Status-Msg, HTTP_RESPONSE_HEADERS"
                          view-name="/zip"
                          path="/services/zip/zipcode/{zipcode}/search"
                          reply-timeout="50000">
    <int-http:header name="zipcode" expression="#pathVariables.zipcode"/>
</int-http:inbound-gateway>

EDIT:

i have added the gateway as follows:

<int:gateway id="toHttp" service-interface="com.....domain.MyGW"
 default-request-channel="routingChannel"
 default-reply-timeout="55550" ></int:gateway>

Was the autowire supposed to look as follows?:

@Autowired
private MyGW toHttp;

or

@Autowired
private MyGW gateway;

I used the former:

Message<?> reply = toHttp.callHttp(inMessage);

I don't think it is picking up the routingChannel however.

Answer 1

The proper solution is to not send to the routing channel directly, but to use a Messaging Gateway and have the <gateway/> send to the routing channel.

Since you may or may not return a result (depending on the routing), you should set default-reply-timeout=0 and you'll get null returned from the gateway method in that case.

Alternatively, use a MessagingTemplate and one of its sendAndReceive() methods to send to the routing channel - again you will need a reply timeout of zero if you might not get a reply.

EDIT:

No, I am suggesting this...

<gateway id="toHttp" service-interface="foo.MyGW
     default-request-channel="routingChannel"
     default-reply-timeout="0" />

.

public interface MyGW {
    public Message<?> callHttp(Message<?> message);
}

And, in xyzServiceActivator

@Autowired
private MyGW gateway;

...

    Message<?> reply = myGW.callHttp(m);
...

Or...

@Autowired
private MessageChannel routerChannel;


...
    MessagingTemplate template = new MessagingTemplate(routerChannel);
    template.setReceiveTimeout(0);
...
    Message<?> reply = template.sendAndReceive(m);

or

    Object reply = template.convertSendAndReceive(somePayload);

(with the latter letting the framework taking care of converting to/from messages).