As a sort of follow up to their previous article showing the use of the zend-json-server component to create an XML-RPC service, the Zend blog is back with a different take on the same functionality, this time using zend-xmlrpc.

zend-xmlrpc provides a full-featured XML-RPC client and server implementation. XML-RPC is a Remote Procedure Call protocol using HTTP as the transport and XML for encoding the requests and responses.

[...] Each XML-RPC request consists of a method call, which names the procedure (methodName) to call, along with its parameters. The server then returns a response, the value returned by the procedure.

The post walks you through an example request/response flow and some of the value types allowed in the XML-RPC structure. From there it's on to the code, creating the simple server and an "add" method on the "calculator" service. The post then covers how to integrate this setup with the zend-mvc component and an application based on it. It finishes up with an example of the same kind of functionality only applied in a PSR-7 middleware instead.

Abdul Malik Ikhsan has a post to his site showing how you can integrate the concept of middleware in to the Zend MVC Component of the Zend Framework. Middleware has come into its own with the acceptance of of the PSR-7 standard and several frameworks adopting its structure for request/response handling.

zend-mvc 2.7.0 is coming, beside of the forward compatibility with V3 components, there is new middleware listener that allow us to do Dispatching PSR-7 middleware. The middleware can be an invokable class with __invoke() method.

He shows how, starting with a new project, to create the middleware class (in this case HomeAction) and the __invoke function. He then adds in the "home" route to the module configuration and points it at this HomeAction class. He registers it in the service manager as an InvokableFactory and it magically works. From there he refactors to allow the middleware to work with the ViewModel and change things like templates and variable values.