How to get all word forms of a word?

Question

Data request

The task is to get all the word forms of an arbitrary word in the debian environment of the system.
I would like to use some regular means like ispell, aspell. But it is not at all clear how this can be achieved.
If there are options to take a lib to some programming language, then this is also an acceptable option.
UPD
The language is Russian.

Answer 1

If you are talking about declensions and cases, then I used the morpher.ru API, if you need one line in the console, you can write a bash script using cURL.