API:Compare

Category:MediaWiki action API

GET request to get the difference between two pages.

MediaWiki version:
≥ 1.18

API documentation

action=compare

(main | compare)

Get the difference between two pages.

A revision number, a page title, a page ID, text, or a relative reference for both "from" and "to" must be passed.

Specific parameters:
Other general parameters are available.
fromtitle

First title to compare.

fromid

First page ID to compare.

Type: integer
fromrev

First revision to compare.

Type: integer
fromslots

Override content of the revision specified by fromtitle, fromid or fromrev.

This parameter specifies the slots that are to be modified. Use fromtext-{slot}, fromcontentmodel-{slot}, and fromcontentformat-{slot} to specify content for each slot.

Values (separate with | or alternative): main
fromtext-{slot}

Text of the specified slot. If omitted, the slot is removed from the revision.

This is a templated parameter. When making the request, {slot} in the parameter's name should be replaced with values of fromslots.
fromsection-{slot}

When fromtext-{slot} is the content of a single section, this is the section identifier. It will be merged into the revision specified by fromtitle, fromid or fromrev as if for a section edit.

This is a templated parameter. When making the request, {slot} in the parameter's name should be replaced with values of fromslots.
fromcontentformat-{slot}

Content serialization format of fromtext-{slot}.

This is a templated parameter. When making the request, {slot} in the parameter's name should be replaced with values of fromslots.
One of the following values: application/json, application/octet-stream, application/unknown, application/x-binary, text/css, text/javascript, text/plain, text/unknown, text/x-wiki, unknown/unknown
fromcontentmodel-{slot}

Content model of fromtext-{slot}. If not supplied, it will be guessed based on the other parameters.

This is a templated parameter. When making the request, {slot} in the parameter's name should be replaced with values of fromslots.
One of the following values: GadgetDefinition, JsonSchema, MassMessageListContent, NewsletterContent, Scribunto, SecurePoll, css, flow-board, javascript, json, sanitized-css, text, translate-messagebundle, unknown, wikitext
frompst

Do a pre-save transform on fromtext-{slot}.

Type: boolean (details)
fromtext
Deprecated.

Specify fromslots=main and use fromtext-main instead.

fromcontentformat
Deprecated.

Specify fromslots=main and use fromcontentformat-main instead.

One of the following values: application/json, application/octet-stream, application/unknown, application/x-binary, text/css, text/javascript, text/plain, text/unknown, text/x-wiki, unknown/unknown
fromcontentmodel
Deprecated.

Specify fromslots=main and use fromcontentmodel-main instead.

One of the following values: GadgetDefinition, JsonSchema, MassMessageListContent, NewsletterContent, Scribunto, SecurePoll, css, flow-board, javascript, json, sanitized-css, text, translate-messagebundle, unknown, wikitext
fromsection
Deprecated.

Only use the specified section of the specified 'from' content.

totitle

Second title to compare.

toid

Second page ID to compare.

Type: integer
torev

Second revision to compare.

Type: integer
torelative

Use a revision relative to the revision determined from fromtitle, fromid or fromrev. All of the other 'to' options will be ignored.

One of the following values: cur, next, prev
toslots

Override content of the revision specified by totitle, toid or torev.

This parameter specifies the slots that are to be modified. Use totext-{slot}, tocontentmodel-{slot}, and tocontentformat-{slot} to specify content for each slot.

Values (separate with | or alternative): main
totext-{slot}

Text of the specified slot. If omitted, the slot is removed from the revision.

This is a templated parameter. When making the request, {slot} in the parameter's name should be replaced with values of toslots.
tosection-{slot}

When totext-{slot} is the content of a single section, this is the section identifier. It will be merged into the revision specified by totitle, toid or torev as if for a section edit.

This is a templated parameter. When making the request, {slot} in the parameter's name should be replaced with values of toslots.
tocontentformat-{slot}

Content serialization format of totext-{slot}.

This is a templated parameter. When making the request, {slot} in the parameter's name should be replaced with values of toslots.
One of the following values: application/json, application/octet-stream, application/unknown, application/x-binary, text/css, text/javascript, text/plain, text/unknown, text/x-wiki, unknown/unknown
tocontentmodel-{slot}

Content model of totext-{slot}. If not supplied, it will be guessed based on the other parameters.

This is a templated parameter. When making the request, {slot} in the parameter's name should be replaced with values of toslots.
One of the following values: GadgetDefinition, JsonSchema, MassMessageListContent, NewsletterContent, Scribunto, SecurePoll, css, flow-board, javascript, json, sanitized-css, text, translate-messagebundle, unknown, wikitext
topst

Do a pre-save transform on totext.

Type: boolean (details)
totext
Deprecated.

Specify toslots=main and use totext-main instead.

tocontentformat
Deprecated.

Specify toslots=main and use tocontentformat-main instead.

One of the following values: application/json, application/octet-stream, application/unknown, application/x-binary, text/css, text/javascript, text/plain, text/unknown, text/x-wiki, unknown/unknown
tocontentmodel
Deprecated.

Specify toslots=main and use tocontentmodel-main instead.

One of the following values: GadgetDefinition, JsonSchema, MassMessageListContent, NewsletterContent, Scribunto, SecurePoll, css, flow-board, javascript, json, sanitized-css, text, translate-messagebundle, unknown, wikitext
tosection
Deprecated.

Only use the specified section of the specified 'to' content.

prop

Which pieces of information to get.

diff
The diff HTML.
diffsize
The size of the diff HTML, in bytes.
rel
The revision IDs of the revision previous to 'from' and after 'to', if any.
ids
The page and revision IDs of the 'from' and 'to' revisions.
title
The page titles of the 'from' and 'to' revisions.
user
The username and ID of the 'from' and 'to' revisions. If the user has been revision deleted, a fromuserhidden or touserhidden property will be returned.
comment
The comment on the 'from' and 'to' revisions. If the comment has been revision deleted, a fromcommenthidden or tocommenthidden property will be returned.
parsedcomment
The parsed comment on the 'from' and 'to' revisions. If the comment has been revision deleted, a fromcommenthidden or tocommenthidden property will be returned.
size
The size of the 'from' and 'to' revisions.
timestamp
The timestamp of the 'from' and 'to' revisions.
Values (separate with | or alternative): comment, diff, diffsize, ids, parsedcomment, rel, size, timestamp, title, user
Default: diff|ids|title
slots

Return individual diffs for these slots, rather than one combined diff for all slots.

Values (separate with | or alternative): main
To specify all values, use *.
difftype

Return the comparison formatted as inline HTML.

One of the following values: inline, table, unified
Default: table
Example:
Create a diff between revision 1 and 2.
api.php?action=compare&fromrev=1&torev=2 [open in sandbox]

Example

GET request

Compare the current revisions of two different pages.

Response

{
    "compare": {
        "fromid": 1882196,
        "fromrevid": 739666518,
        "fromns": 10,
        "fromtitle": "Template:Unsigned",
        "toid": 32371774,
        "torevid": 909784724,
        "tons": 10,
        "totitle": "Template:UnsignedIP",
        ...
    }
}

Sample code

Python

#!/usr/bin/python3

"""
    compare.py

    MediaWiki Action API Code Samples
    Demo of `Compare` module: Compare the current revisions of two different pages
    
    MIT license
"""

import requests

S = requests.Session()

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

PARAMS = {
    'action':"compare",
    'format':"json",
    'fromtitle':'Template:Unsigned',
    'totitle':'Template:UnsignedIP'
}

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

print(DATA)

PHP

<?php
/*
    compare.php

    MediaWiki Action API Code Samples
    Demo of `Compare` module: Compare the current revisions of two different pages
    
    MIT license
*/

$endPoint = "https://en.wikipedia.org/w/api.php";
$params = [
    "action" => "compare",
    "format" => "json",
    "fromtitle" => "Template:Unsigned",
    "totitle" => "Template:UnsignedIP"

];

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

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

echo( $output );

JavaScript

/*
    compare.js

    MediaWiki Action API Code Samples
    Demo of `Compare` module: Compare the current revisions of two different pages

    MIT license
*/

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

var params = {
    action: "compare",
    format: "json",
    fromtitle: "Template:Unsigned",
    totitle: "Template:UnsignedIP"

};
request.get({ url: url, qs: params }, function(error, res, body) {
    if (error) {
        return;
    }
    console.log(body);
});

MediaWiki JS

/*
    compare.js

    MediaWiki Action API Code Samples
    Demo of `Compare` module: Compare the current revisions of two different pages

    MIT license
*/

var params = {
    action: "compare",
    format: "json",
    fromtitle: "Template:Unsigned",
    totitle: "Template:UnsignedIP"
},
api = new mw.Api();

api.get( params ).done( function ( data ) {
console.log( data );
} );

Possible errors

Code Info
compare-relative-to-nothing No 'from' revision for torelative to be relative to.
compare-relative-to-deleted Cannot use torelative=value relative to a deleted revision.
missingrev-title No current revision of title title.
baddiff The diff cannot be retrieved. One or both revisions do not exist or you do not have permission to view them.
missingcontent-revid Missing content for revision ID revid.
invalidtitle Bad title "title".
nosuchpageid There is no page with ID id.
missingtitle-byname The page name doesn't exist.
nosuchrevid There is no revision with ID id.
missingcontent-revid-role Missing content for revision ID id for role main.
compare-nosuchfromsection There is no section name in the 'from' content.
compare-nosuchtosection There is no section name in the 'to' content.
compare-maintextrequired Parameter fromtext-main is required when fromslots contains main (cannot delete the main slot).
compare-maintextrequired Parameter totext-main is required when toslots contains main (cannot delete the main slot).
compare-notext Parameter $1 cannot be used without $2.
compare-no-title Cannot pre-save transform without a title. Try specifying fromtitle or totitle.
compare-nofromrevision No 'from' revision. Specify fromrev, fromtitle, or fromid.
compare-notorevision No 'to' revision. Specify torev, totitle, or toid.
sectionsnotsupported Sections are not supported for content model model.
sectionreplacefailed Could not merge updated section.
missingparam At least one of the parameters fromtitle, fromid, fromrev, fromtext, fromrelative and fromslots is required.
missingparam At least one of the parameters totitle, toid, torev, totext, torelative and toslots is required.

Parameter history

  • v1.32: Introduced fromslots, toslots, fromtext-{slot}, fromsection-{slot}, fromcontentformat-{slot}, fromcontentmodel-{slot}, totext-{slot}, tosection-{slot}, tocontentformat-{slot}, tocontentmodel-{slot}
  • v1.30: Introduced frompst, torelative, topst, prop
  • v1.20: Introduced fromid, toid

Additional notes

To get the difference between two pages, a revision number, a page title, or a page ID for both from and to must be passed.

Relative comparison at first and last revision

  • You can ask for a relative comparison to prev at the first revision of a page, this will result in the full text of the first revision being returned as the diff. Note that this is not accurate, since in some cases there may be default content for the page before its first revision. The fromrevid property will be absent from the results.
  • Similarly, you can ask for the next relative comparison on the last revision of a page.
  • (Note: this is the last revision as of the writing of this topic. Because the page is protected, it probably should not change.) The result is an empty diff, and the torevid will be absent. Unlike most revision comparisons, these results will change if a new revision is created.

This behavior in the API is historical. It isn't consistent with the conceptual model of page history as a series of revisions. There is no previous revision to compare against the first revision, nor is there a next revision to compare against the last. Because of this, future versions of MediaWiki may give different results for this API call.

Using the HTML output

The prop values diff and parsedcomment return HTML snippets. The diff HTML is a list of table rows (‎<tr> elements) which should be embedded into a table with at least the following markup:

<table class="diff">
  <colgroup>
    <col class="diff-marker">
    <col class="diff-content">
    <col class="diff-marker">
    <col class="diff-content">
  </colgroup>
  <tbody>
    DIFF HTML SNIPPET GOES HERE
  </tbody>
</table>

To display metadata as well, e. g. the user or comment, add extra rows and place the metadata inside a <td colspan="2"> element.

To make sure this diff displays correctly (e. g., that the diff marker and content columns aren’t the same width), you can add the mediawiki.diff.styles ResourceLoader module to your page:

<link rel="stylesheet" href="https://www.mediawiki.org/w/load.php?modules=mediawiki.diff.styles&only=styles">

If you want to display the parsedcomment, you will likewise want to add the mediawiki.legacy.shared module, which includes some basic styles for comments and autocomments:

<link rel="stylesheet" href="https://www.mediawiki.org/w/load.php?modules=mediawiki.legacy.shared&only=styles">

And if you want to display both the diff and the parsedcomment HTML on the page, you can combine these two tags into one:

<link rel="stylesheet" href="https://www.mediawiki.org/w/load.php?modules=mediawiki.legacy.shared|mediawiki.diff.styles&only=styles">
Category:MediaWiki action API