[pmwiki-users] Redirecting pages to external URLs

[Petko Yotov]

On Thursday 31 December 2009 15:42:51, Bernard Bel wrote :
> This feature is the page redirection to an external URL.  On my sites we
>  have taken the habit of writing significant acronyms between square
>  brackets so that they automatically point at a specific page. For
>  instance, [[CNAM]] links to the "CNAM" page and this page has an external
>  redirection to
>  http://fr.wikipedia.org/wiki/Caisse_nationale_d%27assurance_maladie
> 
> This has the immense advantage that (1) we do not need to repeat external
>  URLs and (2) any change in an external URL can be updated by editing the
>  unique page that contains it.

You can add a custom "extredirect" markup like this :

 (:extredirect http://external.site.com/dir/file.html#anchor :)

Adding the following code to local/config.php will enable it :

  ## (:extredirect:)
  if(!@$_POST['preview']) {
    Markup('extredirect', '<include', '/\\(:extredirect\\s+(\\S.*?):\\)/ei',
      "Redirect(\$pagename, trim(PSS('$1')))");
    $SaveAttrPatterns['/\\(:extredirect\\s.*?:\\)/i'] = ' ';
  }

For security reasons, this is NOT recommended on open public wikis - any wiki 
page could be redirected to external (ad/porn/phishing) websites.

Also note that when you save the page, you'll be immediately sent out of the 
wiki. Re-editing the page requires to type the ?action=edit url in your 
browser. These may be confusing and hard for less experienced users.

For these reasons, I wouldn't recommend enabling external redirects, if you 
can just place a link on the redirect page. Visitors will have an additional 
step to go out - a single link is not hard to click. You can always edit the 
page to update a broken link. It is possible to edit it from within the wiki. 
You can also have multiple links for the visitor, like :

  Liens externes :
  *  [[http://www.ameli.fr/ | Site institutionnel]]
  *  [[http://fr.wikipedia.org/wiki/CNAM | Page de CNAM sur Wikipédia]]

  Pages de ce site possedant un lien vers cette page :
  (:pagelist link={*$FullName}:)

This may even fit nicely in the Category feature, where, in pages, you just 
use a link [[!CPAM]] instead of [[CPAM]].

> To make things clear I would not migrate to a wiki that does not permit
>  external redirection. (MoinMoinWiki, which I almost opted for, does it
>  nicely.)

Hmmm... :-)

> A quick search on the web led me to these suggestions:
> 
> http://www.mail-archive.com/pmwiki-users@pmichaud.com/msg00372.html
> 
> However none of them does a single external redirection from a single page.

They may be easier to bulk-create, to control and to manage in the long run. 
They're definitely safer.

>  In addition, I don't understand how a call of a page might open
>  "local/Site.Redirect.php". I guess that some extra PHP code is required in
>  "local/config.php"s.

If the file exists, local/Site.Redirect.php is included automatically in 
pmwiki.php, when a visitor goes to the page [[Site/Redirect]].

Petko