Create how to on custom local components

[droumis]

• import a component by its module path, e.g. you can do my_library.some_module.MyTransform

• Also made the install page more explicit about python installation after a good talk with @Hoxbro.

• Also included some minor fixes like syntax highlighting and a couple of links

[codecov-commenter]

Codecov Report

Merging #343 (bbfbcbd) into master (95b3e7d) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #343   +/-   ##
=======================================
  Coverage   67.22%   67.22%           
=======================================
  Files          71       71           
  Lines        7340     7340           
=======================================
  Hits         4934     4934           
  Misses       2406     2406           

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[maximlt]

Maybe this is still WIP but shouldn't this How-to actually describe how to write the code of a custom compoment? I.e. you have to create a class that inherits from a base class, you have to define transform_type to define the name by which you will be referring to that component in the spec, you have to implement the apply method with this signature and returning that type of object, create Parameters, specify _field_params, etc.

[droumis]

@maximlt, according to the plan by @philippjfr , there are separate how-to guides planned for

• Build a Custom Source
• Build a Custom Filter
• Build a Custom Transform
• Build a Custom View

This PR is much simpler and is intended just to cover how to use those components, once created.

[philippjfr]

Yeah, let's keep that separate. However one thing that wasn't documented elsewhere and should be here is that you can import a component by its module path, e.g. you can do my_library.some_module.MyTransform.

[droumis]

@philippjfr can we merge this now?

[github-actions]

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.