How do I make php page return a 503 error (or anything non-200) [duplicate]

Question

A former developer wrote or client-server api in PHP. It simply sends messages as xml using post/response in a very simplistic fashion. The problem is that even when there is an error (ex: invalid arguments passed into the server side) we get a HTTP 200 response with a page like this

<h4>Unknown error!</h4> 

In firebug I can see that the actually HTTP response is a 200. How can we send a different response (ie:503) when we programatically detect in our php code that it is appropriate to do so.

Answer 1

Use PHP's header function to send the code (along with the HTTP version and any other headers you need). More complete info:

When to send HTTP status code?

http://php.net/manual/en/function.header.php

http://en.wikipedia.org/wiki/List_of_HTTP_status_codes

header('HTTP/1.1 503 Service Temporarily Unavailable'); header('Status: 503 Service Temporarily Unavailable'); header('Retry-After: 300');//300 seconds 

Answer 2

I worked on a site that had been hacked and had to use HTACCESS to do this.

<IfModule mod_rewrite.c>   RewriteEngine on   # let this (iescaped) IP address see the real site:  # RewriteCond %{REMOTE_ADDR} !^123.45.67.89   RewriteCond %{REQUEST_URI} !/maintenance.php$ [NC]   RewriteCond %{REQUEST_URI} !.(jpe?g?|png|gif|css|js) [NC]   RewriteRule .* /maintenance.php [R=503,L]  </IfModule>