Python in a Nutshell

Distributed Computing

There are many standards for distributed computing, from simple Remote Procedure Call (RPC) ones to rich object-oriented ones such as CORBA. You can find several third-party Python modules supporting these standards on the Internet.

The Python standard library comes with support for both server and client use of a simple yet powerful standard known as XML-RPC. For in-depth coverage of XML-RPC, I recommend the book Programming Web Services with XML-RPC, by Simon St. Laurent and Joe Johnson (O’Reilly). XML-RPC uses HTTP as the underlying transport and encodes requests and replies in XML. For server-side support, see Section 19.2.2.4 in Chapter 19. Client-side support is supplied by module xmlrpclib.

The xmlrcplib module supports a class ServerProxy, which you instantiate to connect to an XML-RPC server. An instance s of ServerProxy is a proxy for the server it connects to. In other words, you call arbitrary methods on s, and s packages up the method name and argument values as an XML-RPC request, sends the request to the XML-RPC server, receives the server’s response, and unpackages the response as the method’s result. The arguments to such method calls can be of any type supported by XML-RPC:

Boolean

Constant attributes True and False of module xmlrpclib (since module xlmrpclib predates the introduction of bool into Python, it does not use Python’s built-in True and False values for this purpose)

Integers, floating-point numbers, strings, arrays

Passed ...