InstantCommons
InstantCommons é um recurso do MediaWiki para permitir o uso de qualquer arquivo de mídia carregado no Wikimedia Commons em qualquer instalação MediaWiki.
Análise
As of novembro de 2023, Wikimedia Commons, the central media repository hosted by the Wikimedia Foundation, contains over 100 million files. Each of these files is available under a free content license or in the public domain; there are no other restrictions of use beyond those relating to use of official insignia or trademarks. Licenses which limit commercial use are considered non-free.
Ao mesmo tempo que o entendimento sobre o Commons aumenta, o desejo de sites de terceiros em usar e contribuir com seu conteúdo também aumentou. Atualmente é tecnicamente possível carregar imagens diretamente dos servidores da Wikimedia no contexto de qualquer página da web. Tal hotlinking é permitido, mas é problemático por várias razões: It is currently technically possible to load images directly from Wikimedia's servers in the context of any webpage. Such hotlinking is allowed, but it is problematic for multiple reasons:
- Não respeita os termos da licença da imagem e não permite que outros metadados sejam transportados de forma confiável
- Além de não creditar devidamente o autor do arquivo de mídia, também não dá crédito à Wikimedia
- Consome largura de banda da Wikimedia a cada visualização de página (a menos que a imagem tenha sido armazenada em cache no lado do cliente ou por meio de um proxy; esta funcionalidade está atualmente desabilitada por padrão)
- Não facilita as operações de imagem úteis, tais como a geração de miniatura e de legenda e é difícil de usar no contexto de uma Wiki, particularmente para operações de formatação de layouts
- Seé vincula à URLs como identificadores de recursos, o que complica o espelhamento
- Cria um uso web externo impossível de rastrear, onde qualquer alteração no lado do Wikimedia afeta necessariamente esses usuários externos
- Não permite a visualização off-line, o que é crucial para os países que têm apenas o acesso à rede intermitente.
InstantCommons seeks to address all this by providing an easy method for (cached) loading of images and metadata from Wikimedia's servers. Although caching functionality is part of the objective, it has been disabled since MediaWiki 1.27.2/1.28.1. InstantCommons was first implemented within MediaWiki, allowing for all MediaWiki image operations (thumbnailing, captioning, galleries, etc.) to be performed transparently. Other wiki engines can implement InstantCommons-like functionality using the API operations described below.
Basic feature set
During the installation, the site administrator can choose whether to enable InstantCommons. Ideally, however, the feature should be enabled by default (provided a writable upload directory is specified) to allow the largest possible number of users to use Wikimedia Commons content.
If the feature is enabled, the wiki behaves like a Wikimedia project, that is, if an image or other media file is referred to which exists on Commons, it can be included in a wiki page like a locally uploaded file by specifying its name. Local filenames take precedence over Commons filenames.
Configuração
Default method: $wgUseInstantCommons
For enabling InstantCommons in MediaWiki version 1.16 or later, it is sufficient to add this line to your LocalSettings.php (see $wgUseInstantCommons for details):
$wgUseInstantCommons = true;
Classic InstantCommons with local thumb caching
Default InstantCommons as enabled through $wgUseInstantCommons uses thumb images hotlinked from Wikimedia.[1]
This may be slow and may also interfere with file caching (broken links).
If you would like to generate and use thumbs on your local server, do not use $wgUseInstantCommons.
Instead, insert this code into LocalSettings.php as described here: Manual:$wgForeignFileRepos#Usage.
$wgForeignFileRepos[] = [
'class' => ForeignAPIRepo::class,
'name' => 'commonswiki', // Must be a distinct name
'apibase' => 'https://commons.wikimedia.org/w/api.php',
'hashLevels' => 2,
'fetchDescription' => true, // Optional
'descriptionCacheExpiry' => 43200, // 12 hours, optional (values are seconds)
'apiThumbCacheExpiry' => 86400, // 24 hours, optional, but required for local thumb caching
];
Using files via InstantCommons
With InstantCommons enabled, you can choose any image from Wikimedia Commons (e.g. this one), click the "Use this file" button (the button with the wiki icon 
next to) and paste the markup in your wiki.
In our example, pasting
[[File:Wikipedia-Marker-commons.svg|thumb|A picture from Wikimedia Commons embedded in this Wiki]]
will render the thumbnail (as can be seen on the right side of this page).
Note that when using files in this way you will still need to respect any licensing and other file use legal requirements - see Commons:Reusing content outside Wikimedia.
Troubleshooting
Common thumbnail sizes
Since early 2026, Wikimedia image servers prefer to generate thumbnail images with predefined widths.
The rate limiting applied to sizes outside of the predefined widths is quite strict.
The Common thumbnail sizes can be used along with $wgThumbnailSteps to limit the image sizes used in the <img> HTML tags generated by MediaWiki.
When active these settings make your MediaWiki emit HTML that puts whatever width and height attribute is appropriate on generated <img> tags while also selecting the exact match or next largest width from the step sizes for the image requested from upload.wikimedia.org.
Adding $wgThumbnailSteps = [20, 40, 60, 120, 250, 330, 500, 960, 1280, 1920, 3840]; and $wgThumbnailStepsRatio = 1; in your LocalSettings.php will make your MediaWiki match the expected sizes.
User-Agent Policy
Since late 2025, Wikimedia Commons may categorize API requests from your server as unidentified and throttle or block its requests. This is due to enforcement of the Wikimedia Foundation User-Agent Policy and protects against increases in automated scraping.
Prior to MediaWiki 1.45, the User-Agent header in InstantCommons did not include a source URL, as required by the policy. If you encounter a rate limit message when using InstantCommons, please upgrade to MediaWiki 1.45.0 (or MediaWiki 1.39.14+, 1.43.4+, or 1.44.1+) which sets a compliant header that includes the wiki's server URL. High traffic wikis may additionally need to follow Bot traffic requirements by verifying the server's IP range.
HTTPS
Since June 2015, Wikimedia Commons can only be accessed using HTTPS. Some installs may be missing their root certificate store which prevents MediaWiki from contacting Commons over HTTPS. If InstantCommons stopped working, try:
- Installing the php curl extension. (It is generally more reliable, and more likely to have proper certificates already installed.) On Debian/Ubuntu:
sudo apt-get install php-curl
- Verifying you have an up-to-date certificate store. If you have the php curl extension installed, follow the instructions on webaware or Talk:InstantCommons#Stop_working.
- Make sure the PHP function
curl_exec()is not disabled in your web server.
SElinux
If your server OS implements SElinux, please take a look at the dedicated section on the SELinux settings page, and make sure HTTPD scripts and modules can access the network successfully. If SElinux prevents HTTPD scripts and modules from connecting to WikiMedia Commons repository, the InstantCommons feature will simply not work.
Behind a firewall
If the server on which the wiki runs is behind a firewall, the wiki server must be granted outgoing http/https requests to commons.wikimedia.org and upload.wikimedia.org, for Instant Commons to work. The IP address ranges are found at wikitech:IP addresses.
If you need to use a proxy to access the internet from behind the firewall, see $wgHTTPProxy.
Ver também
- Manual:$wgForeignFileRepos – for the same functionality as InstantCommons but with other wikis
- PhotoCommons – WordPress plug-in to provide the same functionality
- Examples of sites which are using InstantCommons
- Extension:QuickInstantCommons