Module development and code questions

When I visit a node list page e.g. https://my_site/en/admin/content/my_nodes with default English language all links for each node in the list shown with English prefix "en" in its URL i.e. https://my_site/en/my_node/custom_alias/50 , so far so good ...                      ...      

The following is an example .routing.yml file:

example.content:
  path: '/example' 
  defaults: 
    _controller: '\Drupal\example\Controller\ExampleController::content' 
    _title: 'Hello World'
  requirements: 
    _permission: 'access content' 

As you can see, the keys '_controller', '_title' and '_permission' begin with an underscore.

I already figured out, that every key without an underscore under the 'defaults'-key is considered to be a parameter to the controller.

Hi everyone,

How can I add the XML Sitemap field configuration when I create a taxonomy term programmatically?

I'm using the XML Sitemap module that comes with Drupal 9 core and I've configured the module so that the relevant vocabulary is included in the sitemap.

In order to get an idea, I created a term and tried to see the field as follows:

Is there a way to tag an option in a dropdown menu as "selected"?  

For example in HTML  <option value="gg" selected="selected">g g: (No Grey)</option>

I've tried to find one but came up empty.  

Hello, I'm currently working on creating custom error pages on Drupal 9.

I know I can easily add customized pages for 404 and 403, but how can I use custom pages for all possible errors like 401, 403, 500, 502, and etc.?

I found this module: https://www.drupal.org/project/error_page but I couldn't see the result, not so sure which part I messed up with. And some say I could add custom hooks - but I'm not familiar with php and twig, so it was very hard for me to follow with no detailed guidance.

Hi,

I am looking for which SAML module to use for my need : automatically connect to a Drupal 9 site users connected from a client authentication platform (custom client system) with their profile information.
The customer connects from his unique portal and can then choose which application to use, he will be connected with his information.
Is SAML the best choice and which module would you recommend ?

Thanks