API:Categories

This page is part of the MediaWiki Action API documentation.

MediaWiki version:

≥ 1.11

GET request to view {{ll|Help:Categories|categories}} associated with a page or pages.

This module can be used as a {{ll|API:Query#Generators|generator}}.

API documentation

The following documentation is the output of Special:ApiHelp/query+categories, automatically generated by the pre-release version of MediaWiki that is running on this site (MediaWiki.org).

Special:ApiHelp/query+categories

Example

GET request

GET request to view categories on a page.

api.php?action=query&format=json&titles=Janelle%20Monáe&prop=categories [try in ApiSandbox]

Response

{
    "continue": {
        "clcontinue": "13828397|Afrofuturists",
        "continue": "||"
    },
    "query": {
        "pages": {
            "13828397": {
                "pageid": 13828397,
                "ns": 0,
                "title": "Janelle Mon\u00e1e",
                "categories": [
                    {
                        "ns": 14,
                        "title": "Category:1985 births"
                    },
                    {
                        "ns": 14,
                        "title": "Category:21st-century American actresses"
                    },
                    {
                        "ns": 14,
                        "title": "Category:21st-century American singers"
                    },
                    ...
                ]
            }
        }
    }
}

Sample code

Python

#!/usr/bin/python3

"""
    get_categories.py

    MediaWiki API Demos
    Demo of `Categories` module: Get categories associated with a page.

    MIT License
"""

import requests

S = requests.Session()

URL = "https://en.wikipedia.org/w/api.php"

PARAMS = {
    "action": "query",
    "format": "json",
    "prop": "categories",
    "titles": "Janelle Monáe"
}

R = S.get(url=URL, params=PARAMS)
DATA = R.json()

PAGES = DATA["query"]["pages"]

for k, v in PAGES.items():
    for cat in v['categories']:
        print(cat["title"])

PHP

<?php
/*
    get_categories.php

    MediaWiki API Demos
    Demo of `Categories` module: Get categories associated with a page.

    MIT License
*/

$endPoint = "https://en.wikipedia.org/w/api.php";
$params = [
    "action" => "query",
    "format" => "json",
    "prop" => "categories",
    "titles" => "Janelle Monáe"
];

$url = $endPoint . "?" . http_build_query( $params );

$ch = curl_init( $url );
curl_setopt( $ch, CURLOPT_RETURNTRANSFER, true );
$output = curl_exec( $ch );
curl_close( $ch );

$result = json_decode( $output, true );

foreach( $result["query"]["pages"] as $k => $v ) {
    foreach( $v["categories"] as $k => $v ) {
        echo( $v["title"] . "\n" );
    }
}

JavaScript

/*
    get_categories.js

    MediaWiki API Demos
    Demo of `Categories` module: Get categories associated with a page.

    MIT License
*/

var url = "https://en.wikipedia.org/w/api.php"; 

var params = {
    action: "query",
    format: "json",
    prop: "categories",
    titles: "Janelle Monáe"
};

url = url + "?origin=*";
Object.keys(params).forEach(function(key){url += "&" + key + "=" + params[key];});

fetch(url)
    .then(function(response){return response.json();})
    .then(function(response) {
        var pages = response.query.pages;
        for (var p in pages) {
            for (var cat of pages[p].categories) {
                console.log(cat.title);
            }
        }
    })
    .catch(function(error){console.log(error);});

MediaWiki JS

/*
	get_categories.js

	MediaWiki API Demos
	Demo of `Categories` module: Get categories associated with a page.

	MIT License
*/

var params = {
		action: 'query',
		format: 'json',
		prop: 'categories',
		titles: 'Janelle Monáe'
	},
	api = new mw.Api();

api.get( params ).done( function ( data ) {
	var pages = data.query.pages,
		p;
	for ( p in pages ) {
		pages[ p ].categories.forEach( function ( cat ) {
			console.log( cat.title );
		} );
	}
} );

Possible errors


Code	Info
clshow	Incorrect parameter - mutually exclusive values may not be supplied.

Parameter history

v1.20: Introduced cldir
v1.16: Introduced clprop=hidden
v1.15: Introduced clcategories
v1.14: Introduced clshow
v1.13: Introduced clcontinue, cllimit, clprop=timestamp