Joomla components use Models to fetch data (like articles) from the database. We would like to introduce two new Plugin Events in component models, which allows you to tweak queries using plugins.

If you want to change the query of for instance the front-end ArticlesModel, then you can't.
Or you have to use a cumbersome workaround: create a system plugin that loads your own changed copy of the ArticlesModel before Joomla does. However, such a "model override" is difficult and there's no option like with Template Overrides to see if there are any changes in the Joomla core model after Joomla updates.

Therefore we would like to have two new plugin events where you can hook into the filtering and into the query of the Model to modify the query.

Use case

com_content - back-end

In the back-end via Content > Articles you get an overview of all articles.
If you want to add an extra column to display the intro image of an article, you can create a template override.
However, the "images" field that contains the "intro_image" is not in the query to retrieve the articles.
Add a database query in the template override is not the right way, and might slow down the page.
And if you want to add an extra filter in the override (e.g. to filter images on (non) availability of the intro image), then you can't.

It would be handy to have two new plugin events in /administrator/components/com_content/src/Model/ArticlesModel.php in the methods:

• populateState()
• getListQuery()

With new plugin events in those methods, you could hook into them.
And have your plugin add new filters and extra queries to the $query object.

com_content - front-end

The front-end Category Blog loads all articles from a specific category.
With new plugin events you can have your own plugins modify the query to add or remove items from the list.

It would be handy to have two new plugin events in
In /components/com_content/src/Model/CategoryModel.php

• populateState()
• getItems()

With new plugin events in those methods, you could hook into them.
And have your plugin add new filters and extra queries to the $query object.