Usage

In order to generate customized <meta> tags, property assignments have to be added to `$GLOBALS['smtgTagsProperties'](no assigments = no additional <meta>` tags).

<meta> tags are mapped (by name) to properties. In case you want to generate multiple values from different properties to the same <meta> tag then separate those property assigments by comma.

If a tag contains a og: it is identified as an [Open Graph][opg] <meta> tag and annotated using the meta property="" description.

Configuration

• `$GLOBALS['smtgTagsProperties']` array of "tag => property" or "tag => callback" assignments. If a given property has multiple values (including subobjects) on a wiki page, the values are concatenated into a single string separated by commas.
  • callback is a function that ought to have the following signature: function( OutputPage $outputPage ): string. This is the place to assign MediaWiki system messages, page properties like its title or plain strings to tags
• `$GLOBALS['smtgTagsPropertyFallbackUsage']in case it is settrue` then the first property that returns a valid content for an assigned tag will be used exclusively.
• `$GLOBALS['smtgTagsStrings']can be used to describe static content for an assigned<meta>tag.
• Tags specified in$GLOBALS['smtgTagsBlacklist']` are generally disabled for free assignments.
• `$GLOBALS['smtgMetaPropertyPrefixes']` to set which prefixes to meta elements should result in rendering as properties rather than names. For example, all Open Graph (Facebook) meta tags should render as properties.

Example settings

Simple settings

Best for wikis using templates on all content pages

$GLOBALS['smtgTagsProperties'] = [

    // Standard meta tags
    'keywords' => [
        'Has keywords', 'Has another keyword'
    ],
    'description' => 'Has some description',
    'author' => 'Has last editor',

    // Summary card tag
    'twitter:description' => 'Has some description',

    // Open Graph protocol supported tag
    'og:title' => 'Has title'
];

$GLOBALS['smtgTagsStrings'] = [

    // Static content tag
    'some:tag' => 'Content that is static'
];

$GLOBALS['smtgMetaPropertyPrefixes'] = [ 

    // Open Graph prefixes
    'og:',
    'fb:'
];

Advanced settings

Best for wikis not using templates on all content pages

$GLOBALS['smtgTagsProperties'] = [

    // Standard meta tags
    'keywords' => [
        'Has keywords',
        'Has another keyword',
        function( OutputPage $outputPage ): string {
            // Redirects to the page are collected as keywords.
            $redirects = $outputPage->getContext()->getTitle()->getRedirectsHere();
            $redirect_titles = [];
            foreach ( $redirects as $redirect ) {
                $redirect_titles[] = $redirect->getText();
            }
            return implode( ', ', array_unique( $redirect_titles ));
        }
    ],
    'description' => [
        'Has some description',
        function( OutputPage $outputPage ): string {
            global $wgLanguageCode;
            $title = $outputPage->getContext()->getTitle()->getText();
            $main_page = wfMessage( 'mainpage' )->inLanguage( $wgLanguageCode ?: 'ru' )->escaped();
            $site_name = wfMessage( 'pagetitle-view-mainpage' )->inLanguage( $wgLanguageCode ?: 'ru' )->escaped();
            $subtitle = $title !== $main_page ? wfMessage( 'tagline' )->inLanguage( $wgLanguageCode ?: 'ru' )->escaped() : '';
            return $title === $main_page ? $site_name : $title . '. ' . $subtitle;
    }],
    'author' => 'Has last editor',

    // Summary card tag
    'twitter:description' => 'Has some description',

    // Open Graph protocol supported tag
    'og:title' => 'Has title'
];

$GLOBALS['smtgTagsPropertyFallbackUsage'] = true;

$GLOBALS['smtgTagsStrings'] = [

    // Static content tag
    'some:tag' => 'Content that is static'
];

$GLOBALS['smtgMetaPropertyPrefixes'] = [ 

    // Open Graph prefixes
    'og:',
    'fb:'
];