vk: improve code quality

[blacktrub]

Proposed changes

I wanted to improve code quality of a VK back-end, because I had a problem when I wanted to extend it. So I decided it's a good idea to move vk_api function to class implementation, so we can use an inheritance with full power.

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (PEP8, lint, formatting, renaming, etc)
• Refactoring (no functional changes, no api changes)
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• Lint and unit tests pass locally with my changes
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[codecov]

Codecov Report

Merging #617 (eb9dfd2) into master (1ea27e8) will decrease coverage by 0.00%.
The diff coverage is 48.38%.

@@            Coverage Diff             @@
##           master     #617      +/-   ##
==========================================
- Coverage   76.92%   76.92%   -0.01%     
==========================================
  Files         317      317              
  Lines        9630     9641      +11     
  Branches      962      964       +2     
==========================================
+ Hits         7408     7416       +8     
- Misses       2071     2073       +2     
- Partials      151      152       +1     

Flag	Coverage Δ
unittests	76.92% <48.38%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
social_core/backends/vk.py	43.63% <48.38%> (+3.23%)	⬆️

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[nijel]

Seems like access_token is always present, maybe the code can be simplified?

[blacktrub]

I'm afraid it's not, when we call the method from VKAppOAuth2, we don't have access_token.

[nijel]

Ah, I missed the isAppUser call when reviewing, and lack of test coverage there made me think it is not used. Can you add tests for that?

[blacktrub]

Sure, I'll add.

[nijel]

@blacktrub Any chance to get to this? 😄