API:Tutorial

=Tutorial for MediaWiki's RESTful web service API=

What is API used for?? Bots, Ajax, Gadgets, Other things.

Roan says generally any Ajax feature is going to use the api.php entry point. But right now the easiest thing to do is to write a bot or to use the API clients.

Definitions

 * REST API for MediaWiki
 * exposes things MediaWiki has in the database or otherwise understands
 * does not include semantic stuff like "definition of a word in Wiktionary" or even "lead paragraph of an article"
 * usage: send HTTP requests (GET or POST) to the api.php URL, receive XML or JSON or other formats. You'll usually want JSON or XML.
 * https://en.wikipedia.org/wiki/JSON and https://en.wikipedia.org/wiki/XML and https://en.wikipedia.org/wiki/Representational_state_transfer (RESTful)

There are other things that also get casually called the MediaWiki API, like the internal interfaces that extensions and special pages can hook into. We're not talking about that right now, just the web API.


 * (possibly talk about how it works from the back end, if people ask)

How to use it
Follow along by using https://en.wikipedia.org/wiki/Special:ApiSandbox -- query is what you will usually want.
 * Entry point: http://en.wikipedia.org/w/api.php
 * or any other wiki
 * Talk about versioning and how non-WMF wikis might have different version of MediaWiki and thus the API
 * https works too!
 * Parameters are passed in query string. Not passing any --> help page
 * Example query: ?action=query&titles=San_Francisco&prop=images&imlimit=20&format=jsonfm
 * action=query is used for most read actions, separate action= modules exist for write actions
 * titles= takes one or more titles for the query to operate on
 * prop=images lists the images on a page; lots of other stuff in prop=, list=, meta=
 * limit= sets the max # of results. Default is 10, 'max' works
 * popular values for format= : xml, json, xmlfm (default), jsonfm
 * State-changing actions (e.g. editing)
 * POST requests only
 * two-step process involving token
 * details of individual actions are complex, read the docs
 * example: ?action=query&titles=Foo&prop=info&intoken=edit for obtaining edit token, then POST to  ?action=edit&title=Foo&...

Example nouns to look up:
 * Kanichar
 * Kolar_Gold_Fields
 * Cooperative_principle
 * MS_Riverdance

Magic recipes
Nonobvious and very useful.
 * prop=info for basic page info
 * prop=revisions for page history
 * prop=revisions&rvprop=content for page wikitext
 * action=parse for page HTML
 * Doing crazy stuff
 * multiple titles with titles=Foo|Bar|Baz
 * multiple modules with &prop=images|templates&list=allpages|blocks
 * generators (kind of like UNIX pipes) with &titles=Foo&generator=links&prop=revisions

Roan talks about jQuery & AJAX

 * TODO: add sample code from Roan

Resources

 * Getting help
 * Autogenerated documentation: api.php with no parameters such as https://en.wikipedia.org/w/api.php
 * Documentation on mediawiki.org: https://www.mediawiki.org/wiki/API:Main_page (details about specific modules/parameters often outdated, autogenerated docs are authoritative)
 * The API Query Sandbox -- example https://en.wikipedia.org/wiki/Special:ApiSandbox
 * https://lists.wikimedia.org/mailman/listinfo/mediawiki-api -- mediawiki-api@lists.wikimedia.org
 * mediawiki-api-announce@lists.wikimedia.org - PLEASE subscribe because we tell you about breaking changes, which happen a few times every year. https://lists.wikimedia.org/mailman/listinfo/mediawiki-api-announce
 * #mediawiki on irc.freenode.net
 * If you want to do bots et al., please talk to the admins of that wiki ahead of time -- resource for contacting them to go here
 * me! (Roan Kattouw)