Joomla. How to get and change content before output?

Question

Joomla

Friends, tell me about the issue.
Is it possible to get content in joomla before it is given to the browser.
The task is this: you need to replace the pseudo-variables in the content with their corresponding values.
In the article, I want to make a shortcode like .
While rendering the page, I want to fetch the article, find the shortcode, parse it, and replace that shortcode with the content that my function will return.
And only then return the content to the browser.

Answer 1

If the shortcode needs to be parsed in an article, then this is done by creating a plugin of the content type and catching the onContentBeforeDisplay event.
Documentation for creating a content plugin. https://docs.joomla.org/J3.x:Creating_a_content_plugin