Add no cache and Optimize the Dockerfile format

[99Kies]

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Clean up the Dockerfile code format and remove the cache residue after pip install

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Codecov Report

Merging #1451 into trunk will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##            trunk    #1451   +/-   ##
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  Coverage   86.15%   86.15%           
=======================================
  Files         375      375           
  Lines       78630    78630           
  Branches     7770     7770           
=======================================
  Hits        67743    67743           
  Misses       7953     7953           
  Partials     2934     2934           

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[Kami]

Thanks for the contribution.

I'll test it locally and ensure that it's working as expected.

Besides that - we recently dropped support for Python < 3.4 so we can also remove those Python versions from Dockerfile.

[Kami]

As per my comment on the PR - once I confirm it's working, I will go ahead and split into two Dockerfiles - Dockerfile.python3 and Dockerfile.python2.

In the future, we can also get rid of python2 one all together since we don't officially support it anymore anyway.

[99Kies]

yes, Upgrade to python3 is definitely necessary.

[Kami]

I receive the following error when I try to build a fresh Docker image:

  File "/usr/local/lib/python2.7/dist-packages/importlib_metadata/__init__.py", line 9, in <module>
    import zipp
ImportError: No module named zipp

It appears to be related to old version of pip - I will look into upgrading it as part of the Dockerfile step.

[Kami]

This actually won't work correctly, targets need to be passed to tox as a single argument.

So either:

tox -epy1,py2...

Or:

["tox", "-e", "py1,py"]

[99Kies]

i got it.

[99Kies]

This is my fault, I haven’t tested it because of time.

[Kami]

Thanks for the original contribution, but after trying to get it to work locally it turned out it needs much more work.

It was likely broken and not working for quite a while now.

Here are the changes I needed to make to get it in sync with latest master and everything passing - Kami@bf25ca3, Kami@e2a5cbc, Kami@a3eb0a2.

I will also see if I can get it to run on our CI - if we don't do that, it's better to remove it all together from this repo. Otherwise will just get out of date and broken again sooner or later.

And in the future, we also need to update base image to be something more recent than Ubuntu 16.04 which defaults to Python 3.

[Kami]

Here we go - Kami@ca9c274.

I also pushed a change to use newer Ubuntu version and Python 3 for running tox target. Now it's more or less in sync with latest master / trunk and we just need to sort running it on CI.

[Kami]

Alright, took a couple of more fixes (Kami@c2edeeb, Kami@15c1ffe), but it's now passing and also hooked up to CI - https://travis-ci.org/github/Kami/libcloud/jobs/682629304.

Only downside is that this CI target is quite slow (8 -10 minutes). But as mentioned above, not having it hooked up to CI is worse than not having this Dockerfile at all :)

[99Kies]

Alright, took a couple of more fixes (Kami@c2edeeb, Kami@15c1ffe), but it's now passing and also hooked up to CI - https://travis-ci.org/github/Kami/libcloud/jobs/682629304.

Only downside is that this CI target is quite slow (8 -10 minutes). But as mentioned above, not having it hooked up to CI is worse than not having this Dockerfile at all :)

nice, :)