What is XML-RPC?Quite interesting. Somebody browsing LiveJournal complemented me on LiveJournal's templated style system, documenting the LiveJournal protocol, and proposed I look into XML-RPC if I get bored. It does look pretty interesting. Of course, it makes the clients a bit tougher to write, but it looks like there are already implementation for every language an LJ client is written in already, so it may not be an issue. However, the reality of the situation is that I haven't much time, and old clients will always exist, so making two protocols is kinda silly, but maybe for future projects.... or if I hit severe limitations in the current protocol, I could always phase it out.
It's a spec and a set of implementations that allow software running on disparate operating systems, running in different environments to make procedure calls over the Internet. It's remote procedure calling using HTTP as the transport and XML as the encoding. It's designed to be as simple as possible, while allowing complex data structures to be transmitted, processed and returned.