User:Hadseys/Organising/Redirects

See also: Wikipedia:Redirect

A redirect is a page starting with:

#REDIRECT [[pagename]]

where pagename is the target page.

Extra text after the #REDIRECT command and link is ignored. It is rendered only in preview and in a diff.

How it appears to the user

If the redirect target is an existing page in the same project, going to the redirect page by means of a link, the URL, or the Go button, results in the redirect target page, just like following the link. However, the browser shows the URL of the redirect page, and the target page shows a small notice below the top title to indicate you arrived here indirectly.

For example, if somebody goes to Help:Redirection, then they will end up at this page instead, and the top of the page will look like:

Help:Redirect

To get the canonical URL of the target page in your browser's address bar, click the article tab.

If the redirect target is a non-existing page in the same project, or to a page in another project, one simply arrives at the redirect page.

When a page called for inclusion is a redirect page, the redirect target is included instead, with the same parameters, without any redirect message. A double redirect does not work (see below).

Restrictions

As a simple way to avoid problems with infinite recursion, if the redirect target is another redirect page, the second redirect is not applied.

A redirect target cannot depend on a variable, template, or parser function. When attempting this, the restriction does not become apparent in the preview (see also the section below on the rendering of a redirect page), but only after saving.

A code like %70 in a redirect disables it, although the link works from the redirect page.

Note also that different projects have different specifications on what can be redirected. On en.wiktionary.org, the multilingual dictionary, most redirects are prohibited by policy.

Purposes of a redirect

• Allow access in the case that a pagename is provided:
  • which is an alternative term for the subject
  • which is a term for a subtopic (in this case one may use a redirect to a section)
  • which uses alternative capitalization and hyphenation
  • which uses alternative spelling
  • which has a common misspelling
• Provide a way of conveniently going to a page (shortcut).
• Keep links to a page active after it has been moved (even if internal links are updated, this still applies for links from outside; also for links in edit summaries).

Special purposes

• Conveniently linking indirectly to a page, without the need for a Piped link. However, a piped link is in some respects even better than relying on a redirect, see Comparison with piped link.
• Allowing a link title independent of the final link target; one creates a page whose name is the desired link title, and which redirects to the desired target page. See e.g. w:Template:Ft, containing [[30.48 cm|ft]], with the page w:30.48 cm redirecting to w:Foot (unit of length). The link title "30.48 cm" informs in the hover box about the unit "ft" even without following the link to the article about this unit. See also Help:Advanced_editing for another technique with a similar result.

When creating new redirects, bear in mind that creating too many redirects can clutter up the search results page, which can hinder users. Also, don't spend too much time creating redirects - often it's more important to spend time improving the quality of the target page. A piped link is another way to make a link to a page with a name which does not occur in the first page.

Creating a redirect

If you're creating a new redirect, start a new page, write #REDIRECT [[pagename]] (or #redirect [[pagename]]) at the top of the page, where pagename is the name of the target page. Here is an example. If you're replacing an existing page with a redirect, for example after merging a duplicate page, go to the page, edit it, and replace the existing text with #REDIRECT [[pagename]].

The page will not redirect if there is anything on the page before the redirect. Also, there must be no spaces between the # and the REDIRECT.

Extra text after the #REDIRECT command and link is ignored. It is rendered only in preview and in a diff, see [1], [2], and [3]. Category-tags are not ignored. If a category is set, the redirect-page is listed in the category it belongs to. When following the link from the category page to the redirect page then as usual the redirect is applied.

An edit summary is automatically provided, with the text according to MediaWiki:Autoredircomment, but only if no edit summary is supplied (as opposed to the automatic edit summary in section editing, which can be supplemented by the user).

Rendering of the redirect page

After you save the redirect page, you get sent to a page with the string "&redirect=no" in the URL. Thus the just created redirect page is shown, not the page to which it redirects. The redirect page should look something like:

Help:Redirection

Help:Redirect

After the page title, the content of MediaWiki:Redirectpagesub (by default the text "Redirect page"), a bent arrow, and the link to the redirect target is rendered. This link shows the canonical form of the target. As mentioned above, the text after the link to the redirect target is ignored, except for category tags.

This does not apply in the preview of a redirect page: this ignores the special meaning of the redirect syntax, so it shows a one-item numbered list, with the link rendered as an ordinary link, and followed by the extra content. Compare [4] with the preview of its edit page [5].

To see your redirect working, use your address bar to delete that part of the URL. Alternatively, create a link on another page to your redirect, and then follow that link.

Changing a redirect

When changing a redirect target to a different page, or turn a redirect page into a regular page, you must go to the redirect page. To do so, click on a link to the redirect page. Then look for the link to the redirect page at the top of the page you've been redirected to; e.g.

Once you get to the redirect page, click Edit this page. You can then either change the target of the redirect or replace the redirect with a brand new page.

Another way to get to the redirect page: Go to the target page, and click "What links here". This will show you all the back-links from that page, including redirects. To change a redirect, click on it, and then click on Edit this page as above.

Deleting a redirect

Administrators can delete redirects in the same way as any other page. There may be project-specific guidelines on when this is appropriate.

The moving function

When a page is renamed/moved with the moving function, a redirect is automatically created from the old to the new name, and also one for the corresponding talk page.

If the new page name is occupied by a redirect that has only one edit in its history and targeted to the old page name, it is replaced by the page being moved. If the redirect has more than one history entry, or the redirect target is somewhere else, then it must be moved by an administrator.

Redirect to special targets

Interwiki redirects and redirects to special pages

Interwiki redirects and redirects to special pages have been disabled, try e.g. Help:Interwiki redirect demo and Help:Redirect to special page demo.

Use direct interwiki links (or direct links to Special pages) without redirect, or a soft redirect (non-automatic).

A redirect to an anchor

One may redirect to an anchor, in particular a section. Help:Section linking and redirects is an example and its target also provides more info (it does not work for every environment).

Section redirects are supposed to work from r18220 onwards. See bugzilla:218. If it does not work, you will be redirected to the page but you will not be sent to the section.

A redirect to a page in the image or category namespace

On Meta and Wikipedia a redirect to an image page or to a category shows the editable text only. To get the full page after being redirected, use the link "Image", or "Category", respectively.

On Commons a redirect to a category gives the full page, but not the subcategories and pages in the redirect page (if that is also a category).

To prevent a page that redirects to a category from appearing in the category; precede the word Category with a colon like so : #REDIRECT [[:Category:Glossary]]

Images linking to a specific page

There are ways to make an image link to a specified page, some which work especially well on Mediawiki sites that support embedding external images. For possibilities see Help:Navigational image.

CSS class

With the new preprocessor an internal link to a redirect page has CSS class "mw-redirect". This can be useful to make them stand out, for clean-up work involving bypassing redirects.

Redirect and/or link to non-existing page

When B is a subtopic of A, and B does not have its own page, or at least not with additional info, there are the following possibilities:

1. redirect B to A, use the backlink to go from A to B (disadvantage: not very inviting to create a new content page B; inconvenient if A has many backlinks)
2. link A to B ("red link") as invitation or preparation for creating page B; use the backlink to go from B to A (disadvantage: not obvious for newbie, much less convenient than automatic redirect, especially if B has many backlinks)
3. both (indirect self-link on A). To go from A to B, click the link from A to B, which brings you back to A, and use the link in the redirect message (for detecting a redirect see above; however, there is no distinction between a redirect back, and an onward redirect) (disadvantage, as far as not yet mentioned: not obvious for newbie)
4. ditto but with a soft redirect from B to A, i.e. a page only containing something like "See [[A]]"; one can see at A that B is very short using the stub feature (disadvantages: a soft redirect is non-standard; people who do not know about its reason may change it in a regular redirect; is a little less convenient than automatic redirect; requires stub feature setting)
5. B is a redirect, link from A to B with "redirect=no", or link to B's edit page, e.g. Template and start page Template, respectively.

In the 3rd and 4th case, especially if A has a list of links to pages B, one can mark the links with more info, e.g. by bolding, and explain the marking.

Force all redirects to be client side redirects (HTTP 302 Temporary Redirect)

(for MediaWiki 1.9.0)

(modified code by Uriah Anthony Stephenson-Ward | uriah@diyinfo.org | DIYinfo.org)

What?

This piece of code forces all redirects to be done by the client, by issuing them a 302 Temporary Redirect to the new pages specific location.

Why?

A lot of search engines decrease your pages rank if they discover duplicated content. The traditional Redirect method allows a huge amount of duplication, and doesn't redirect as nicely. This also allows you to use images for navigation. Additionally it can be a limitation/annoying to not see the full redirected pages location in the address bar, and having the annoying "Redirected from" link.

Warning: This hack will increase your servers network load somewhat, for 99% of MediaWiki servers this will be negligible, but I wouldn't see Wikipedia doing this mod any time soon!

How?

Open "includes\Article.php" and edit the function "followRedirect()"

Change line 94 (approximately) from "return $rt;" to "return $rt->getFullURL();"

The whole function should now look like this:

    /**
     * @return mixed false, Title of in-wiki target, or string with URL
     */
    function followRedirect() {
        $text = $this->getContent();
        $rt = Title::newFromRedirect( $text );
        
        # process if title object is valid and not special:userlogout
        if( $rt ) {
            if( $rt->getInterwiki() != '' ) {
                if( $rt->isLocal() ) {
                    // Offsite wikis need an HTTP redirect.
                    //
                    // This can be hard to reverse and may produce loops,
                    // so they may be disabled in the site configuration.
                    
                    $source = $this->mTitle->getFullURL( 'redirect=no' );
                    return $rt->getFullURL( 'rdfrom=' . urlencode( $source ) );
                }
            } else {
                if( $rt->getNamespace() == NS_SPECIAL ) {
                    // Gotta handle redirects to special pages differently:
                    // Fill the HTTP response "Location" header and ignore
                    // the rest of the page we're on.
                    //
                    // This can be hard to reverse, so they may be disabled.
                    
                    if( $rt->isSpecial( 'Userlogout' ) ) {
                        // rolleyes
                    } else {
                        return $rt->getFullURL();
                    }
                }
                return $rt->getFullURL();
            }
        }
        
        // No or invalid redirect
        return false;
    }

See also

• Detecting links to redirects using the stub feature.
• Redirects in search results - proposed software changes.
• Redirected user pages considered harmful
• w:Wikipedia:Redirect
  • Deletion policy on Wikipedia for redirects