API:Main page

 MediaWiki has three outward-facing interfaces:
 * the MediaWiki API, which provides convenient access to wiki features, data and meta-data. Read this article for an overview of the API.
 * the Special:Export page, which provides bulk export of wiki content as XML. Read the Export help article on meta.wikimedia.org for more information.
 * the standard web-based interface (which you are likely using right now). Read Manual:Parameters to index.php for information on using the web-based interface.

You may also be looking for the internal extension interface, which allows PHP developers to add new functionality to a MediaWiki installation.

'''This is an introductory overview. See the menu bar on the right for more detailed sub-topics.'''

If you want to monitor a MediaWiki installation, or create a bot to automatically maintain one, you can use the MediaWiki web service API. The web service API provides direct, high-level access to the data contained in MediaWiki databases. Client programs can log in to a wiki, get data, and post changes automatically by making HTTP requests to the web service. Supported clients include bots, thin web-based JavaScript clients such as Navigation popups and LiveRC, end-user applications such as Vandal Fighter, and other web sites (Toolserver's utilities).

On new MediaWiki installations, the web service is enabled by default, but an administrator can disable it.

A simple example
This URL tells English Wikipedia's web service API to send you the content of the main page:

http://en.wikipedia.org/w/api.php?format=xml&action=query&titles=Main%20Page&prop=revisions&rvprop=content

Use any programming language to make an HTTP GET request for that URL (or just visit that link in your browser), and you'll get an XML document which includes the current wiki markup for the page titled "Main Page". This is the web service API in action.

Let's pick that URL apart to show how it works.

The endpoint
This is the endpoint. It's like the home page of the Mediawiki web service API. This URL is the base URL for English Wikipedia's API, just as  is the base URL for its web site.

If you're writing a program to use English Wikipedia, every URL you construct will begin with this base URL. If you're using a different MediaWiki installation, you'll need to find its endpoint and use that instead. All Wikimedia wikis have endpoints that follow this pattern:

http://en.wikipedia.org/w/api.php     # English Wikipedia API http://nl.wikipedia.org/w/api.php     # Dutch Wikipedia API http://commons.wikimedia.org/w/api.php # Wikimedia Commons API

Now let's move on to the parameters in the query string of the URL.

The format
This tells the Wikimedia web service API that we want data to be returned in XML format. The API supports many output formats, including JSON, WDDX, XML, YAML and PHP's native serialization format.

The action
This is the 'action'. The MediaWiki web service API supports over fifty actions, and they're all documented in the API reference. In this case, we're using "query" to tell the API that we want to get some data.

The "query" action is one of the API's most important actions, and it has extensive documentation of its own. What follows is just an explanation of a single example.

Action-specific parameters
The rest of the example URL contains parameters used by the "query" action. Here, we're telling the web service API that we want information about the Wiki page called "Main Page". (The %20 comes from percent-encoding a space.) You can ask for more than one page at a time: see the query documentation for details.

This parameter tells the web service API that we are interested in a particular revision of the page. Since we're not specifying any revision information, the API will give us information about the latest revision--the main page of Wikipedia as it stands right now.

Finally, this parameter tells the web service API that we want the content of the latest revision of the page. If we passed in  instead, we'd get the latest page content and the name of the user who made the most recent revision.

Again, this is just one example. Queries are explained in more detail here, and the API reference lists all the possible actions, all the possible values for, and so on.

Getting started
Before you start using the MediaWiki web service API, be sure to read these documents:


 * The FAQ.
 * The page about input and output formats
 * The page about errors and warnings
 * Any policies that apply to the wiki you want to access, such as (for Wikimedia Foundation wikis) our terms of use. These terms apply to you when you access or edit using the web service API, just as they do when you use your web browser.

Beyond that point, what you need to read depends on what you want to do. The right-hand menu links to detailed, task-specific documentation, and some more general guidelines are given below.

Identifying your client
When you make HTTP requests to the MediaWiki web service API, be sure to specify a  header that properly identifies your client. Don't use the default  provided by your client library, but make up a custom header that includes the name and the version number of your client: something like "MyCuteBot/0.1".

On Wikimedia wikis, if you don't supply a  header, or you supply an empty or generic one, your request will fail with an HTTP 403 error. See our User-Agent policy. Other MediaWiki installations may have similar policies. e If you are calling the API from browser-based JavaScript, you won't be able to influence the  header: the browser will use its own. There is currently no other mechanism for a browser-based client to identify itself.

Logging in
Your client will need to log in if:


 * it needs to obtain information or carry out an action that is restricted to users with certain rights
 * it is making large queries that would be inefficient without the higher per-request limits reserved for accounts with certain rights

On wikis that allow anonymous editing, it's possible to edit through the API without logging in, but it's highly recommended that you do log in. On private wikis, logging in is required to use any API functionality.

For the technical details concerning logging in, see the login manual page.

If your client is written in JavaScript, it'll usually act with the credentials of the user who's running it. In this case, you won't need to login using the web service API--you'll just need to ensure that the user has logged in through the web interface.

Application-specific user accounts
Rather than having your application log in as yourself, you may want to create a separate user account just for your application. This is especially important if your application:


 * is carrying out automated editing or some other bulk operation.
 * invokes large or performance-intensive queries.

With a separate account, the changes made by your application can be easily tracked, and special rights (usually a "bot" user group) can be applied to the application's account. Some wikis have a policy related to automated editing, and/or a procedure for dealing with "bot" user group requests.

Making your requests cacheable
If your requests obtain data that can be cached for a while, you should take steps to cache it, so you don't request the same data over and over again. Some clients may be able to cache data themselves, but for others (particularly JavaScript clients), this is not possible.

Per the HTTP specification, POST requests cannot be cached. Therefore, whenever you're reading data from the web service API, you should use GET requests, not POST.

Also note that a request cannot be served from cache unless the URL is exactly the same. If you make a request for, and cache the result, then request for  , the URL will be different the second time and your client will not use the cache--even though the data is the same!

You should take care to normalize the URLs you send to the MediaWiki web service, so that slightly different user input won't cause you to make waste time on unnecessary HTTP requests. You can normalize a list of page titles by removing duplicates and sorting the titles alphabetically. Similar techniques will work for other kinds of data.

Useful links
The menu bar on the right side of this page links to more detailed, task-specific documentation. Here are some links having to do with the API as a whole:


 * The API sandbox on English Wikipedia makes it easy to try out different actions interactively.
 * The API reference contains automatically-generated descriptions of all actions and parameters.
 * Hook into Wikipedia information using PHP and the MediaWiki API (IBM developerWorks article, 17 May 2011)
 * Mailing list for notifications and questions: API mailing list
 * Low-traffic mailing list for announcements only (all posts to this list are posted to mediawiki-api as well): mediawiki-api-announce
 * View and report API bugs: Bugzilla (When reporting new bugs, don't forget to set Component=API)
 * Browse the API source code in SVN
 * The current MediaWiki database schema
 * Browse the current database schema in SVN

Archived Links

 * 2006 API discussion