Code

Run cron by drush

drush cron

Add cron hook to a custom module.

/**

 * Implement hook_cron()

 */

function MYMODULE_cron() {

  // Your codes.

}

To make a redirection after user login, we can use the hook hook_user_login().

Note : You cannot use $form_state->setRedirectUrl() directly in the form alter, since it will be overwritten by UserForm::submitForm().

Add remove git tags.

Create a tag

git tag <TAGNAME>

Push tag

git push origin <TAGNAME>

git push --tags

Pull tags

git tag -l

git checkout tags/<TAGNAME>

Yml vs Json

A make a small test to test YAML vs PHP performance. The result is:

Drupal 8 shiped with a powerfull cache API able to set cache according to a context. correct usage of this cache improve the site preformence greatly.

https://www.drupal.org/docs/8/api/cache-api/cache-contexts
https://www.drupal.org/node/2451661

Memcache is caching server allow you to incrise and have great performence on your site. Drupal and memcached work very well and here the full tutorial you need to install and setup memcache server and your drupal instance.

Check module exist

if (\Drupal::moduleHandler()->moduleExists('my_module')) {

    $message = 'Module exist.';

}

else {

    $message = 'Not exists.';

}

 

Method 1. (Classical way)

Use a captcha system like Math captcha, Image captcha, reCaptcha of google....

Step 1. Create a custom module and add the HOOK hook_views_data_alter(&$data). Here module : mymodule

Step 2. Alter views data, Example

You have several mthodes to override 403 / 404 System pages.

Method 1. Set 403 / 404 pages.

You can set the 403 /404 page on "Basic site settings" page

Admin -> Configuration -> System -> Basic site settings

Path /admin/config/system/site-information