How to Set Up an Email Alert for 404s

Keeping track of 404 pages should be on every savvy site owner and developer’s todo list. But who wants to spend time sifting through boring log files?

Rather than digging around files, why not make the task easier with automatic reporting of 404 errors via email?

In today’s Weekend WordPress Project I’ll show you how to set up 404 error email reports.

There’s really nothing to do, just insert the following code in the top of your theme’s 404.php file. If your theme doesn’t have a 404.php file, you’ll need to create one.

<?php // WP 404 ALERTS @ http://wp-mix.com/wordpress-404-email-alerts/

// set status
header("HTTP/1.1 404 Not Found");
header("Status: 404 Not Found");

// site info
$blog = get_bloginfo('name');
$site = get_bloginfo('url') . '/';
$email = get_bloginfo('admin_email');

// theme info
if (!empty($_COOKIE["nkthemeswitch" . COOKIEHASH])) {
$theme = clean($_COOKIE["nkthemeswitch" . COOKIEHASH]);
} else {
$theme_data = wp_get_theme();
$theme = clean($theme_data->Name);
}

// referrer
if (isset($_SERVER['HTTP_REFERER'])) {
$referer = clean($_SERVER['HTTP_REFERER']);
} else {
$referer = "undefined";
}
// request URI
if (isset($_SERVER['REQUEST_URI']) && isset($_SERVER["HTTP_HOST"])) {
$request = clean('http://' . $_SERVER["HTTP_HOST"] . $_SERVER["REQUEST_URI"]);
} else {
$request = "undefined";
}
// query string
if (isset($_SERVER['QUERY_STRING'])) {
$string = clean($_SERVER['QUERY_STRING']);
} else {
$string = "undefined";
}
// IP address
if (isset($_SERVER['REMOTE_ADDR'])) {
$address = clean($_SERVER['REMOTE_ADDR']);
} else {
$address = "undefined";
}
// user agent
if (isset($_SERVER['HTTP_USER_AGENT'])) {
$agent = clean($_SERVER['HTTP_USER_AGENT']);
} else {
$agent = "undefined";
}
// identity
if (isset($_SERVER['REMOTE_IDENT'])) {
$remote = clean($_SERVER['REMOTE_IDENT']);
} else {
$remote = "undefined";
}
// log time
$time = clean(date("F jS Y, h:ia", time()));

// sanitize
function clean($string) {
$string = rtrim($string);
$string = ltrim($string);
$string = htmlentities($string, ENT_QUOTES);
$string = str_replace("\n", "
", $string);

if (get_magic_quotes_gpc()) {
$string = stripslashes($string);
}
return $string;
}

$message =
"TIME: " . $time . "\n" .
"*404: " . $request . "\n" .
"SITE: " . $site . "\n" .
"THEME: " . $theme . "\n" .
"REFERRER: " . $referer . "\n" .
"QUERY STRING: " . $string . "\n" .
"REMOTE ADDRESS: " . $address . "\n" .
"REMOTE IDENTITY: " . $remote . "\n" .
"USER AGENT: " . $agent . "\n\n\n";

mail($email, "404 Alert: " . $blog . " [" . $theme . "]", $message, "From: $email");

?>

Just edit lines 8-10 of the code to add in your personal information. Line 10 is the most important if you want email alerts.

If you want to turn off email reports, just delete the script in its entirety or comment out line 83.

Thanks to WP-Mix for this awesome snippet!

Have a great weekend!

PS: If you are a WPMU DEV member, don’t forget that email hosting is included with your membership.