How to find an appropriate event in Magento?

Question

Sometimes when looking for a convenient event to hook I do a bit of exploratory programming...

• Modify Mage::dispatchEvent with this extra line:

Answer 1

I thought I would post back the code from above, but modified slightly to work right. $magento needed to be assigned, as well as the paths used for grep. Just change /var/www/app to whatever your magento directory is. Copy this script to a file and execute it. You need to have ack-grep installed for it to work properly. Ubuntu users can type "sudo apt-get ack-grep" I believe to install this, or just google ack-grep.

THIS IS A SHELL PHP SCRIPT. IF YOU RUN IT IN A BROWSER, IT LOOKS LIKE A MESS! However, you can do "php whateveryoucallthescript.php >> output.txt" and then open that file in VI or edit it and search for the results you want.

This has been tested on Enterprise 1.11.1.0

/dev/null | grep -v "/var/www/app/code/local" | grep -v "/var/www/downloader/pearlib"`;
    $results    = explode("\n", $results);

    print_error(sprintf("%-100s\t%-4s\t%s\n", "FILE", "LINE", "EVENT"));

    foreach($results as $result) {
        if(!strlen(trim($result))) { continue; }

        $matches        = array();
        preg_match("/([^:]+):(\d+):\W+(.*)/", $result, $matches);

        $file           = str_replace($magento, "", $matches[1]);
        $line           = $matches[2];
        $event          = $matches[3];

        $eventMatches   = array();
        if(preg_match("/Mage::dispatchEvent\('(\w+)'\);/", $event, $eventMatches)) {
            $event      = $eventMatches[1];
            $matchType  = 1;
        } else if(preg_match("/Mage::dispatchEvent\('(\w+)',.*/", $event, $eventMatches)) {
            $event      = $eventMatches[1];
            $matchType  = 2;
        } else if(preg_match("/Mage::dispatchEvent\($/", $event)) {
            $event      = get_next_line_event($file, $line+1, $magento);
            $matchType  = 3;
        } else if(preg_match("/Mage::dispatchEvent\(\"?(['\$a-zA-Z._{}\-> ]+).*/", $event, $eventMatches)) {
            $event      = $eventMatches[1];
            $matchType  = 4;
        } else {
            print "Found unmatcheable event:\n";
            var_dump($event);
        }

        printf("%-100s\t%-4s\t%s\n", $file, $line, $event);
    }

    function get_next_line_event($file, $line, $magento) {
        $cnt        = `cat -n $magento/$file | grep -e "^ *$line"`;
        $cnt        = preg_replace("/^\s*\d*\s*/", "", $cnt);
        $matches    = array();
        if(preg_match("/^'?([\$a-z_>. -]*)'?,$/i", $cnt, $matches)) {
            return $matches[1];
        } else if(preg_match("/^([\$a-z_>. '\-\(\)]*),$/i", $cnt, $matches)) {
            return $matches[1];
        }
        print "Found unmatcheable event:\n";
        var_dump($cnt);exit;
    }  

    function print_error($err) {
        echo $err;
    }

    ?>