WordPress FirePHP plugin

While tracing some code in WordPress i got tired of var_dumps, so i quickly coded FirePHP plugin. All it does is include FirePHP and forces WordPress to load it before other plugins, so that you can use it in plugin development.


It’s tested on WP 2.7 and someone might find it useful! I got few more ideas to implement to make it useful for theme debugging, but that’s another version 😉

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Ivan Weiler

- Technical Educator and Consultant

Ivan is a Technical Educator and Consultant. He gained lots of experience managing some of the most complex Magento projects we had at Inchoo.

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  1. @George n – sounds like you need to address your php.ini setup or .htaccess. Does your error say something along the lines of “Cannot send log data to FirePHP. You must have Output Buffering enabled via ob_start() or output_buffering ini directive”
    In which case you need to google for php ini output buffering, the correct fix will depend upon your server setup and whether you have ssh access.

  2. I am getting the uncaught exception errors too. Is is possible that we can get a breakdown on how to use this plugin. I’m sure I’m not the only only one that wants to use it but am getting errors. Thanks.

  3. Tried this with WP 3.0.1 and works fine (couldn’t get WP_FirePHP to fly).
    Easiest thing in the world to use. Install and activate plugin as per. Then anywhere in your template files just call the fb() function as per FirePHP docs http://www.firephp.org/HQ/Use.htm .
    So I’m working on dynamic sidebars responding to the new Nav Menu structures, so I can call


    to find out which Nav Menus are available.
    Don’t forget to install the FirePHP extension to Firebug too https://addons.mozilla.org/en-US/firefox/addon/6149/

  4. Sorry, I paste the php code again:

    $firephp = FirePHP::getInstance(true);

    $var = array(‘i’=>10, ‘j’=>20);

    $firephp->log($var, ‘Iterators’);

    Thanks in advance!!

  5. @Javier:
    This plugin starts output caching(ob_start()) at init hook.

    I’m not sure if this error has anything to do with my plugin since i see that your firephp class is at /var/www/wordpress2/FirePHPCore/FirePHP.class.php. Or did you change include path?

    If you’re using FirePHP that you included yourself, just try to add ob_start() before any wp output.

    Or just remove any instance of FirePHP if you have it and install v.0.2 of my plugin.

  6. Hello all,

    I am having troubles to get the plugin to work. That’s what i did:

    1) Unzip the plugin into the /plugins directory.
    2) Insert this code in my index.php:

    10, ‘j’=>20);

    $firephp->log($var, ‘Iterators’);


    But then I get the following error:

    Fatal error: Uncaught exception ‘Exception’ with message ‘Headers already sent in /var/www/wordpress2/wp-content/themes/extended/header.php on line 2. Cannot send log data to FirePHP. You must have Output Buffering enabled via ob_start() or output_buffering ini directive.’ in /var/www/wordpress2/FirePHPCore/FirePHP.class.php:949 Stack trace: #0 /var/www/wordpress2/FirePHPCore/FirePHP.class.php(624): FirePHP->newException(‘Headers already…’) #1 /var/www/wordpress2/FirePHPCore/FirePHP.class.php(510): FirePHP->fb(Array, ‘Iterators’, ‘LOG’) #2 /var/www/wordpress2/wp-content/themes/extended/index.php(11): FirePHP->log(Array, ‘Iterators’) #3 /var/www/wordpress2/wp-includes/template-loader.php(27): include(‘/var/www/wordpr…’) #4 /var/www/wordpress2/wp-blog-header.php(16): require_once(‘/var/www/wordpr…’) #5 /var/www/wordpress2/index.php(17): require(‘/var/www/wordpr…’) #6 {main} thrown in /var/www/wordpress2/FirePHPCore/FirePHP.class.php on line 949

    Any help would be really appreciated as I usually develop for wordpress.

    Thanks in advance.

    PS: My server config:

    # Sistema Operativo : Linux
    # Servidor : Apache/2.2.8 (Ubuntu) DAV/2 SVN/1.4.6 PHP/5.2.4-2ubuntu5.5 with Suhosin-Patch
    # Uso de memoria : 26.69 MB
    # Versión de MySQL : 5.0.51a-3ubuntu5.4
    # Modo SQL : No definido
    # Versión de PHP : 5.2.4-2ubuntu5.5

  7. I just cannot get this to work. Installs fine on WP 2.7.1 running php 5. I’ve got both Firebug and Firephp plugins installed. I typed in fb(‘hello’); in my functions.php for just for a test but nothing shows up on the console. Any ideas?

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