Solved Cron tasks

[mdreira]

Hi!

I have an image optimization plugin in Wordpress (dev) that needs wp-cron to work. It's not working with Cloudron's default settings. I don´t know why.

Is it possible that I have to call wp-cron every so often to get it to work? (2 times a day for example)
How should I do it from the Cron tab of the application?

Screenshot: https://prnt.sc/26q7kaa

Thank you.

[girish]

@mdreira wp-cron is automatically configured and you don't have to run/configure things manually. The cron section is only meant for any additional cron tasks that you want to run which are (often) unrelated to the app. You can manually run /app/pkg/cron.sh via the Web Terminal and check if the cron tasks are running or not. Can you please try?

BTW, feel free to post those images inline here. Those links often lead me to some captcha links and hard to get the context for future readers.

[mdreira]

@girish Screeshot: https://prnt.sc/26qbnex

[girish]

@mdreira right, that means that the app has no scheduled events. Is the plugin scheduling any event? Not a WP expert, but you also check with various cron commands like this:

sudo -u www-data -i -- /app/pkg/wp --path=/app/data/public/ cron

See https://developer.wordpress.org/cli/commands/cron/ for subcommands. For example, https://developer.wordpress.org/cli/commands/cron/event/

[girish]

So, I think the command below will list the cron events and schedules. So, if the plugin scheduled it, it will appear below.

sudo -u www-data -i -- /app/pkg/wp --path=/app/data/public/ cron event list

[mdreira]

@girish It seems to me that the plugin task does not appear in the list.

I'm going to discuss this with the plugin folks. I'll tell you something when they answer me.

Thank you!

[mdreira]

@girish Yes, the task was on the list.

The plugin people ask me what is the code with which Cloudron starts wp-cron to see if it is compatible.

EDIT: I have seen the error. Screenshot: https://prnt.sc/26qc3mk

[d19dotca]

@girish Side note but FWIW, it may be worth updating/clarifying the documentation here: https://docs.cloudron.io/apps/wordpress-developer/#cron-tasks

The doc saying "The app is configured to run WordPress cron tasks every minute." seems a bit conflicted with the statement later that reads "WordPress' built-in cron task schedule wp-cron is disabled since it is not effective for low traffic websites."

I believe we're running our own cron tasks in Cloudron which manually invokes the WP-Cron every minute instead of the default behaviour of WP running it itself only when the website is visited, correct?

[girish]

@d19dotca Right... wp-cron with the hyphen refers to the file wp-cron.php which is this PHP code that runs WP cron jobs via apache. Of course, PHP code only runs if someone visits the web site. So, if no one visits your site for an hour, cron jobs are not run. So, on Cloudron (and most other WP hosts), we set up an external scheduler/timer to run the cron jobs.

I guess what is being said is The app is configured to run WordPress' cron tasks every minute without using the built-in wp-cron

[mdreira]

@girish have you seen anything in error log? https://prnt.sc/26qc3mk

EDIT: The plugin guys tell us that the problem is the way we call to wp-cron.

So even though Cloudron calls wp-cron every minute, I would like to call it twice a day more with the typical type of call from the cron tab. Something like:

0 */12 * * * /usr/bin/php -q /public/wp-cron.php >/dev/null 2

This is the type of call that the plugin needs. It's possible?

We are interested in this image optimization plugin because it optimizes images in the cloud without a limit of megabytes. I have to try to make it work.

If you know of another plugin that does the same and works on cloudron, we can switch.

[girish]

@mdreira We use WP CLI to run cron jobs like so:

sudo -u www-data -i -- /app/pkg/wp --skip-themes --path=/app/data/public/ cron event run --due-now

Are you able to run the command above manually and see if it produces the error message ? Also, remove the --skip-themes and check if that helps as well, maybe that's causing the problem. TBH, I am not 100% sure why we have --skip-themes there, it should probably be removed.

[mdreira]

@girish Here I send you the screenshot of the terminal after sending those commands:

Running it like this did not make the plugin work.

The plugin cron task is this:

When the cron executes this task it gives me this error:

Is there any other way to execute that task? I have to get that plugin working. The plugin people don't know what's going on because our cloudron server is something special

[girish]

@mdreira please post the images inline in this forum. You can just ctrl+v the screenshot to paste in the forum. I am afraid those images will go away at some point and this post will be meaningless if those images go away....

[girish]

@mdreira Also, can you tell me which plugin this is? From the screenshot it says weimgoptimizer but https://wordpress.org/plugins/search/weimgoptimizer/ is a not found.

[mdreira]

@girish The plugin is optimizador.io (https://optimizador.io/)

Right now I edit the links of the screenshots and upload the images directly.

[girish]

@mdreira I will give it a try locally to see if I can reproduce the problem.

[girish]

Struggling to get this API key. https://optimizador.io/registro-clave-api/ has no form to fill anything, not sure how to proceed.

[mdreira]

This post is deleted!

[girish]

@mdreira apparently, that page doesn't work in firefox. works in chrome.

[girish]

You can run the specific hook like this

root@d2c84f40-ba29-47fd-87a5-48c873006e89:/app/code# sudo -u www-data -i -- /app/pkg/wp --skip-themes --path=/app/data/public/ cron event run my_schedule_hook

I am getting the same exception you posted.

[mdreira]

@girish Yes, it seems that something is failing

[girish]

@mdreira It seems that global variables are not working. The clue is from this error message:

WordPress database error Table 'c801e5ebba2fb24b.wp_' doesn't exist for query 
        SELECT *
        FROM wp_
        WHERE meta_id = 6
        AND thumb_size = 'we_original_size'
        ORDER BY time DESC
      made by include('phar:///app/pkg/wp/php/boot-phar.php'), include('phar:///app/pkg/wp/vendor/wp-cli/wp-cli/php/wp-cli.php'), WP_CLI\bootstrap, WP_CLI\Bootstrap\LaunchRunner->process, WP_CLI\Runner->start, WP_CLI\Runner->run_command_and_exit, WP_CLI\Runner->run_command, WP_CLI\Dispatcher\Subcommand->invoke, call_user_func, WP_CLI\Dispatcher\CommandFactory::WP_CLI\Dispatcher\{closure}, call_user_func, Cron_Event_Command->run, Cron_Event_Command::run_event, do_action_ref_array('my_schedule_hook'), WP_Hook->do_action, WP_Hook->apply_filters, oiwe_my_schedule_function, oiwe_optimize_concurrent_image_by_att_id, oiwe_isOptimized

The relevant code is:

function oiwe_get_optimization_data_by_attID($id){

        global $wpdb;
        global $OIWE_TABLENAME;

        $table_name = $wpdb->prefix . $OIWE_TABLENAME ;

         $querystr = "
            SELECT *
            FROM $table_name
            WHERE meta_id = $id
        AND thumb_size = 'we_original_size'
                GROUP BY uuid
            ORDER BY time DESC
         ";

        $optimizations = $wpdb->get_results($querystr, OBJECT);

        return $optimizations ;
}

In the above, OIWE_TABLENAME is null . In fact, all the globals in that file are "null" which is why we later get the error that string is expected. My PHP skillz are being put to test...

[girish]

So strange, I cannot figure why this is. There is a constants.php in the plugin. I put the logs below:

<?php

$OIWE_API_URL = "http://apiv1.optimizador.io:80/";
global $OIWE_API_URL ;
$PLUGIN_VERSION = "1.0.22";
error_log('The version is ' . $PLUGIN_VERSION);
global $PLUGIN_VERSION;
error_log('The version is now ' . $PLUGIN_VERSION);

$OIWE_TABLENAME =  "imgoptimizations";
global $OIWE_TABLENAME;

Now, if I run via PHP cli:

root@d2c84f40-ba29-47fd-87a5-48c873006e89:/app/data# php /app/data/public/wp-content/plugins/weimgoptimizer/includes/constants.php
The version is 1.0.22
The version is now 1.0.22

So, the above works as expected. But if I now run this via WP CRON:

root@d2c84f40-ba29-47fd-87a5-48c873006e89:/app/code# sudo -u www-data -i -- /app/pkg/wp --path=/app/data/public/ cron event run my_schedule_hook
The version is 1.0.22
The version is now 

The version is empty for the second one! In fact, all the global things like global $PLUGIN_VERSION; in constants.php become immediately empty . FWIW, the global usage above seems to be incorrect. In PHP AFAIK, global is to declare that you are going to use a global variable and not that a variable has to become global.

[girish]

@mdreira BTW, it seems the plugin uploads all images via http and not https (see the API URL in constants.php).

[mdreira]

@girish As I don't understand anything about php, I don't really know what's going on.

Is the error you're seeing something on our side or is the side of plugin guys?

[girish]

@mdreira I don't understand either. It seems that global variables get reset immediately after global xx when using WP CLI. I don't get why.

[girish]

@mdreira OK, I found the issue. The usage of global is incorrect in the plugin. The global keyword is for stating the use of a global variable (as opposed to 'make this variable global').

With that in mind, the code in the plugin's constant.php is like this:

<?php

$OIWE_API_URL = "http://apiv1.optimizador.io:80/";
global $OIWE_API_URL ;

The above code will break when the above file is included from a "function". This is the case when we use WP CLI where entire WordPress is loaded into a function. So, for example, the rough equivalent is:

function load() {
    require_once(".../constants.php");
}

When it's like above, the global $OIWE_API_URL keyword then says, use OIWE_API_URL from global context, which is not the same as the one you defined one line above (it's a function local variable). So, the solution is to move the global keyword before setting it in constants.php. Like this:

global $OIWE_API_URL ;
$OIWE_API_URL = "http://apiv1.optimizador.io:80/";

// .. do same for other constants in the file ..

Of course, this is why globals are not used in WP plugins. You should use superglobals like $GLOBAL or define or database etc. See https://codex.wordpress.org/Global_Variables and https://onlinewebtutorblog.com/wordpress-global-variables-step-by-step-complete-guide/

[mdreira]

@girish Then.. what should I do?.

Do I have to tell the plugin guys that they should move the globals in constants.php file or rather use superglobals?

I have no idea how to tell them this. Can we do something from our side?

[girish]

@mdreira said in Cron tasks:

@girish Then.. what should I do?.

Sorry, I wasn't clear. Please send the plugin authors the link to my comment. There is nothing we can do, they have to fix the plugin. They can easily reproduce this by running cron tasks using the WP CLI tool outside Cloudron. WP CLI is pretty much part of standard WP - https://make.wordpress.org/cli/handbook/

[mdreira]

@girish you are the best!!

[mdreira]

@girish Just one more question. I guess the problem with global variables is not only in constants.php file, right? Surely there are several files that are involved...

I'm saying this, because I've repositioned the variables in constants.php file like you said, and it still doesn't work.

[girish]

@mdreira TBH, I was only "guessing" what the solution might be after identifying the issue. I don't 100% know for sure if it solves the issue. Are you getting the same error? Did the plugin authors have any comments?

[mdreira]

@girish What I did was modify the constants file like this:

Then I ran the cron:

This time it didn't give any specific error message.

The plugin guys just thanked us for the feedback. I still don't have any concrete answer from them.

[girish]

@mdreira I think one has to debug that plugin more to find other issues, I only found on of the main issues TBH. It's clear the plugin is not designed to work with WP CLI, so I think that it won't work inside Cloudron unless they fix the plugin.

I think if you really need this exact plugin, you have to switch to LAMP stack and then configure cron as however it works with this plugin. Another idea is to maybe make it possible to disable Cloudron's cron and use WP_CRON but this is not really an option for production sites.

[mdreira]

@girish It's a shame, I'll have to change the plugin