Dynamically append to URL's

[Aureole]

I'll try and give you a realistic example:

 

Let's say we have a website, but the database isn't working, but we have a backup server with another copy of the database.

 

How could I dynamically append say "?secondary_db" to all URLs?

 

<?php
// Pseudo code...

if there is an error connecting to the database append a string to all urls

if the url contains the appended string connect to the secondary database instead
?>

[discomatt]

Many, many ways to do this.

 

1: Attempt server1 every time, if it fails, attempt server2.

-Problem: Could take seconds to timeout, making your page execution time annoyingly slow.

 

2: Trigger a flag in an external file. You would check this file on every page execution, and if the flag is set, use server2. You could then set a cron that continually checks if server1 is up, and when successful, remove the flag from the file

-Problem: Requires reading an external file at every page call, and additional code. Also requires a cron, or external script to remove flag.

 

3: Attempt to connect to server1, if failed, store flag in session. If flag is present, use server2

-Problem: Kinda redundant unless you have a session already started, will attempt to connect to server1 again when session expires

[Aureole]

I know there are multiple ways of doing this, but what I was looking for was a way to dynamically append something to the end of URLs... just like PHPSESSID is, if cookies are disabled...

[eddierosenthal]

not that this has anything to do with php -  but you could look into using

the .htaccess file using rewrite_mod and rewrite_mod rules.

you could for example have a rule that says to append a literal string to a url with a pattern matching

algorithm.

not tested:

RewriteEngine On

RewriteRule ^my-literal-page-name\.html$ /my-literal-page-name/anystringyouwanthere  [L]

 

the apache rewrite mod has to be loaded for this to work. but you won't have to restart apache

if you use the .htaccess method.

hope that helps