Fumiki Takahashi

TAROSKY INC.

Kunoichi INC

<p>Have you ever seen an error log like the one below?</p>
<blockquote>
<p>PHP Fatal error: Allowed memory size of xxxxxx bytes exhausted (tried to allocate xxx bytes) in /var/www/wordpress/wp-includes/wp-db.php on line 2007</p>
</blockquote>
<p>This means that <a href="https://www.php.net/manual/en/ini.core.php#ini.memory-limit" rel="nofollow ugc">PHP memory limit</a> is exhausted while retrieving data from a database. In any case, this happens when your site has big data and makes insane loops inside.</p>
<p>But we want to know that <strong>which plugin tried to retrieve data?</strong></p>
<p>Hagakure adds extra information to error.log file when <code>wp-db.php</code> causes memory limit error:</p>
<pre>[08-May-2019 10:28:37 UTC] wpdb Error Backtrace:
#1      Kunoichi\Hagakure\DbLogger->filter_query()      /app/public/wp-includes/class-wp-hook.php       Line 286
#2      WP_Hook->apply_filters()        /app/public/wp-includes/plugin.php      Line 208
#3      apply_filters   /app/public/wp-includes/wp-db.php       Line 1871
#4      wpdb->query()   /app/public/wp-includes/wp-db.php       Line 2579
#5      wpdb->get_results()     /app/public/wp-includes/class-wp-query.php      Line 2979
#6      WP_Query->get_posts()   /app/public/wp-includes/class-wp-query.php      Line 3387
#7      WP_Query->query()       /app/public/wp-includes/post.php        Line 1961
#8      get_posts       /app/public/wp-content/plugins/hagakure/hagakure.php    Line 34
#9      {closure}       /app/public/wp-includes/class-wp-hook.php       Line 286
#10     WP_Hook->apply_filters()        /app/public/wp-includes/class-wp-hook.php       Line 310
#11     WP_Hook->do_action()    /app/public/wp-includes/plugin.php      Line 465
#12     do_action       /app/public/wp-includes/template-loader.php     Line 13
#13     require_once    /app/public/wp-blog-header.php  Line 19
#14     require /app/public/index.php   Line 17
#15     URI: /?p=1</pre>
<p>This log will always follow the memory limit Fatal Error by <code>wp-db.php</code>. Now you can find <code>#8</code> calls <code>get_posts</code> repeatedly.</p>
<p>We recommend watching logs with notification services like <a href="https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/WhatIsCloudWatchLogs.html" rel="nofollow ugc">CloudWatch Logs</a>.<br />
This error occurs in the productional environment, and you may not have a chance to see it occurs.<br />
We use Hagakure with our <a href="https://hosting.kunoichiwp.com/" rel="nofollow ugc">hosting service</a>, please look forward to seeing <a href="https://kunoichiwp.com/blog" rel="nofollow ugc">our blog published</a> and describing the integration!</p>
<p>This plugin also adds debug backtrace to error logs. To modify the error level to a detailed backtrace, define the constant in <code>wp-config.php</code> or somewhere else:</p>
<pre>define( 'HAGAKURE_ERROR_LEVEL', E_NOTICE | E_USER_WARNING | E_WARNING | E_USER_ERROR );</pre>
<p>Besides that, if <code>SAVEQUERIES</code> is set <code>true</code>, the slow query log will be logged with PHP debug backtrace. This helps you to debug.</p>
<h3>Acknowledgements</h3>
<p>The base text for dummy content is “Three Ghost Story” by Charles Dickens. The text file is modified the one of <a href="https://www.gutenberg.org/ebooks/1289" rel="nofollow ugc">Project Gutenberg</a>.</p>


Hagakure – Yet Another Error Reporter

This plugin makes it easy to find the root cause of PHP Fatal error: Allowed memory size of xxxxxx bytes exhausted error. AWESOME.


Great

Looks good

A WordPress plugin to clarify meaningless errors like "Allowed memory size of xxxxxxxx bytes exhausted".

Uffe Fey

<p>This plugin enables safe mode for WordPress. This means:</p>
<ul>
<li>No plugins will be loaded.</li>
<li>A default theme will be temporarily activated (if it is installed).</li>
</ul>
<h4>Why is this useful?</h4>
<p>Whenever something’s wrong with a WordPress site, the first rule of thumb is to disable plugins and revert to the default theme if possible. Depending on the nature of the error, that is not always an option. The back end (dashboard) may also be down or you may not have FTP access to manually disable plugins and themes.</p>
<p><strong>Enter Safe Mode</strong>. Safe Mode will completely disable all plugins and the active theme temporarily for a single page view – ultimately enabling you to log in and remove the offending plugin. (This is not guaranteed to work in all scenarios, please read the disclaimer)</p>
<h4>How does it work?</h4>
<p>If your site crashes due to an upsetting plugin or theme, all you have to do is add a querystring parameter to the URL. Doing that will temporarily disable all plugins for that single page view, as well as temporarily activate a default theme if one is installed.</p>
<p>Let’s say you’re the owner of www.example.com. To enable safe mode for one particular page, you add this to the URL: “?safe_mode=1”.</p>
<p>Bear in mind that you have to do this for every view. The querystring parameter isn’t carried on automatically. So, for instance:</p>
<ul>
<li>If you need to log in, go to: www.example.com/wp-admin/?safe_mode=1</li>
<li>If you need to go to plugin management, go to: www.example.com/wp-admin/plugins.php?safe_mode=1</li>
<li>If you need to go to theme management, go to: www.example.com/wp-admin/themes.php?safe_mode=1</li>
</ul>
<p>When you go to plugin management, all plugins will seem to be deactivated (due to the way Safe Mode works), but you’ll still be able to explicitly deactivate each plugin. Just use the “Deactivate (safe mode)” option.</p>
<h4>What are default themes?</h4>
<p>By default theme, I’m referring to the themes that ships with WordPress, you know, the Twenty “something” ones.</p>
<p>The plugin checks if any of these themes are installed, and if so, activates the first theme it encounters. Thus I highly recommend that you keep one of those themes installed at all times. If you don’t, safe mode will keep your current active theme, and that theme may just be the offender – leaving safe mode useless. Keep this in mind.</p>
<h4>Disclaimer</h4>
<p>This plugin will be able to handle many scenarios, but not all. If your site’s crash is caused by a database crash, or something that simply brings down the PHP parser, like a call to an undefined function, Safe Mode won’t be able to do anything about that.</p>


Safe Mode

I love using Health Check. And starting today I love this as well. 
Using a URL parameter for selective application is ***** alone. 

Keep it up!

Fantastic.

Makes it possible to enable safe mode for WordPress. In safe mode, plugins will not be loaded and the default theme (if installed) will be activated.

Hagakure – Yet Another Error Reporter vs Safe Mode