This example demonstrates a simple process that could be useful when building travel related applications;
It defines two services:
1. Get Weather report based on the ZIP code
2. Get Traffic report based on the ZIP code
It uses real services provided by third party providers.
Get Weather report Service is a SOAP Web Service
Get Traffic report Service is an HTTP Service
This example demonstrates how to configure both:
-ÊHTTP Outbound Gateway - to integrate with HTTP Service
-ÊWS Outbound Gateway - to integrate with WS Service
The diagram below shows the message flow.
ÊÊ Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê weatherPreProcessChannel Ê Ê Ê Ê Ê Ê Ê Ê Ê ÊÊweatherChannel Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê weatherServiceChannel
ÊÊ Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê |------------------------| -> transformer -> |--------------| -> header-enricher -> |---------------------| -> ws:outbound-gatewayÊ
ÊÊ Ê |->ÊgetWeatherByZip(zip) Ê Ê routingChannel Ê Ê Ê Ê Ê /
TravelGateway Ê Ê Ê Ê Ê Ê Ê Ê--> |--------------| -> h-v-r|
ÊÊ Ê |->ÊgetTrafficByZip(zip) Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê | Ê Ê trafficChannel
ÊÊ Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê \ |-----------------| -> http:outbound-gateway Ê ÊÊ
Two services are exposed via the Gateway. The gateway enriches the headers of the message with the
type of request 'weather' or 'traffic' and sends the Message to the 'routingChannel' from which it is retrieved by
HeaderValueRouter (h-v-r) which routes Message to either 'weatherPreProcessChannel' or 'trafficChannel' based
on the value of the REQUEST_TYPE header hat was set by the Gateway.
WS service, requires that the message would be is a certain format. We first need to wrap it into XML request (done by a transformer),
then we need to add a SOAP Header (done by header-enricher). Once Message was properly formated it is sent to ws:outbound-gateway
which replies with XML describing real time weather conditions in a particular ZIP code.
HTTP Service does not require any pre-processing. All we need to do is map HTTP URI variable {zipCode}.
We do it via <uri-variable> element of http:outbound-gateway.
<uri-variable name="zipCode" expression="payload"/>
Here you see we are using Spring Expression Language to bind the value of the payload (zipCode) to this variable.
To run sample execute TravelDemo.class
