RESTful Services - OSB transport headers for passing HTTP header / custom values

            In one of my projects I was implementing the Gateway architecture, where I have grouped together all common activities and will route to the different project /modules, based on relative URI and needs to pass on the http headers.

There is a misconception that HTTP headers can only be passed if the backend Proxies are using transport protocol as HTTP and not local. This is not true, even in the case of local proxies the headers can be passed through. I am explaining how this can be done using the frontend and backend proxies and using local and HTTP transport protocols.

 This is how you fetch the values from header in front –end proxy and set in the outbound to the backend proxy

Transport Protocol -HTTP

This is how the values will be passed in $inbound

    <tran:headers xsi:type="http:HttpRequestHeaders" xmlns:tran="http://www.bea.com/wli/sb/transports">

        <tran:user-header name="http-method" value="GET"/>

        <tran:user-header name="query-string" value="name=George"/>

        <tran:user-header name="relative-URI" value=”Customer/GetCustomerDetails”/>

        <http:Content-Type>text/xml</http:Content-Type>

      </tran:headers>

Transport Protocol -Local

This is how the values will be passed in $inbound

<con:qualityOfService>best-effort</con:qualityOfService>

    <con:request xsi:type="loc:LocalRequestMetaData" xmlns:loc="http://www.bea.com/wli/sb/transports/local" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

      <tran:headers xsi:type="loc:LocalRequestHeaders" xmlns:tran="http://www.bea.com/wli/sb/transports">

        <tran:user-header name="http-method" value="GET"/>

        <tran:user-header name="query-string" value="name=George"/>

        <tran:user-header name="relative-URI" value=”Customer/GetCustomerDetails”/>

      </tran:headers>

Receiving proxy

-----------------------------------

The caller will embedd the values in the user-header name-value pairs.

The receiving proxy can retreive the values  from tp:user-header and pass in the required the name to fetch the corresponding values..The syntax is below.

$inbound/ctx:transport/ctx:request/tp:headers/tp:user-header[@name="relative-URI"]/@value

Similarly you can fetch all the header values in backend proxy.

That’s it from my desk J