Marcus Downing

Enable system logging for WordPress plugin and theme development. This can make it easier to know what your code is doing.
Features include:
<ul>
<li>Log to the system log or to a file</li>
<li>Easily append or embed any value in log messages</li>
<li>Coloured logs indicating strings, numbers, arrays, objects, null values etc.</li>
<li>Extract values from arrays of objects</li>
<li>Optionally exclude AJAX, Javascripts, CSS and any other pattern of URLs.</li>
<li>Intercept PHP errors and log strict warnings</li>
<li>Measure memory usage between two points, or the time taken by various parts of your code</li>
<li>Easy to switch off for production sites</li>
</ul>
<h4>How to use</h4>
Using it is as simple as calling the <code>'log'</code> action in your templates or plugin.
<pre><code><?php do_action('log', 'Some log message'); ?>
</code></pre>
This will produce a line in your system log:
<pre><code>Jun 4 11:23:08 myserver php/mysite.com[1553]: b8e mysite.com/path-to-page: Some log message
</code></pre>
This includes:
<ul>
<li><code>Jun 4 11:23:08</code> – The date and time of the log message</li>
<li><code>myserver</code> – The name of this computer</li>
<li><code>php</code> – The program that produced the message</li>
<li><code>mysite.com</code> – The domain name of the site</li>
<li><code>1553</code> – The process ID of the running PHP process</li>
<li><code>b8e</code> – A random 3-digit code identifying each page request</li>
<li><code>mysite.com/path-to-page</code> – The URL of the request</li>
<li><code>Some log message</code> – Your message</li>
</ul>
For more detailed instructions, see the How to use tab.
<h3>How to use</h3>
To log a message, use the <code>'log'</code> action in your templates or plugins:
<pre><code><?php do_action('log', 'Some log message'); ?>
</code></pre>
This will output the log message:
<pre><code>Some log message
</code></pre>
<h4>Embedding values</h4>
If you include extra parameters, they’ll be added at the end of the log message:
<pre><code><?php do_action('log', 'A number and a string', 17, 'foo'); ?>
</code></pre>
This will produce the log message:
<pre><code>A number and a string: 17, foo
</code></pre>
The value will be formatted correctly depending on its type: integers, strings, arrays, objects, booleans etc. 
You don’t need to check if values are null or empty, they’ll still be output safely.
If you put the code <code>%s</code> into your log message, then one of the arguments will be dropped into the message:
<pre><code><?php do_action('log', 'I have %s numbers', count($numbers), $numbers); ?>
</code></pre>
This will produce the log message:
<pre><code>I have 4 numbers: [9, 16, 307, 1]
</code></pre>
<h4>Selecting fields</h4>
Logging a complete object – such as a WordPress post – can be very large, and sometimes it’s only one or two fields you need. 
If you put a string starting with an exclamation point <code>"!"</code> followed by a list of field names, they will be selected from the following object. 
The following will only show the <code>ID</code> and <code>post_title</code> fields of the post:
<pre><code><?php do_action('log', 'Loaded the post', '!ID,post_title', $post); ?>
</code></pre>
This will produce the log message:
<pre><code>Loaded the post: {ID: 1932, post_title: Test page}
</code></pre>
If you do this with an array of objects, those fields will be selected from each of them. The following will output a list of post <code>ID</code>s:
<pre><code><?php do_action('log', 'Loaded %s posts', count($posts), '!ID', $posts); ?>
</code></pre>
This will produce the log message:
<pre><code>Loaded 3 posts: [1932, 1594, 1103]
</code></pre>
<h4>Coloured logs</h4>
If you have coloured logging switched on, values will appear in different colours to indicate their type. 
This can make for quicker scanning of log files. 
To enable coloured logs, tick the Coloured logs checkbox on the settings page. 
Then use the <code>log.sh</code> script, included with this plugin, to decode and display the coloured log files.

Bang System Logging

Enable system logging for WordPress plugin and theme development.

Brandon Allen

WP Fail2Ban Redux records various WordPress events to your server’s system log for integration with <a href="http://www.fail2ban.org/" rel="nofollow ugc">Fail2Ban</a>.
This plugin is (mostly) a drop-in replacement for <a href="https://wordpress.org/plugins/wp-fail2ban/" rel="ugc">WP fail2ban</a> by <a href="https://charles.lecklider.org/" rel="nofollow ugc">Charles Lecklider</a>.
While WP fail2ban is a great plugin, there are a number of improvements that could be made. In order to facilitate these improvements, a major refactoring of the codebase was necessary.
The core functionality between WP Fail2Ban Redux and WP fail2ban remains the same. WP Fail2Ban Redux is considered to be mostly a drop-in replacement, because all constants have been replaced with filters, and will, possibly, require some upgrade work. Don’t work it’s as simple as implementing the constants.
The following events are recorded by default:
<ul>
<li>Failed XML-RPC authentication attempts.</li>
<li>Successful authentication attempts.</li>
<li>Failed authentication attempts — differentiated by a user’s existence.</li>
<li>Pingback errors.</li>
</ul>
The following events can be enabled via filter:
<ul>
<li>Pingback requests.</li>
<li>Blocked user enumeration attempts.</li>
<li>Authentication attempts for blocked usernames.</li>
<li>Spammed comments.</li>
</ul>
Extra documentation is available on the <a href="https://github.com/thebrandonallen/wp-fail2ban-redux/wiki" rel="nofollow ugc">WP Fail2Ban Redux GitHub Wiki</a>.

WP Fail2Ban Redux

Tiny, Simple and Effective. Works Well.Thanks to developer.

Simple and Effective, Works Well.

Easy, effective, no unnecessary control panel, no premium parts, no boring messages, it just do the work!

Having fail2ban already configured in the server, I installed it on a bunch of WP sites.

Locking repetitive attackers, it saves some server resources peaks.

Really thanks for the plugin.

If you already have fail2ban, this is a must

Records various WordPress events to your server's system log for integration with Fail2Ban.

Bang System Logging vs WP Fail2Ban Redux