Update pip from 19.3.1 to 20.2.4

[vanastassiou]

https://github.com/plotly/streambed/issues/14939

The updated get-pip.py was generated as follows:

curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py

Tested as follows:

1. • Update dds-vendor Dockerfile to install new pip version
2. • Install Dash Enterprise using the above dds-vendor image
3. • Deploy a Dash app with a .buildpacks file containing https://github.com/plotly/heroku-buildpack-python.git#update-pip
4. • exec into Dash app container and /app/.heroku/python/bin/pip --version

[vanastassiou]

@gzork please review.

[vanastassiou]

@BRONSOLO just wanted to check in with you re the test steps and confirm the container to test the pip version in, and how.

[BRONSOLO]

Hey @vanastassiou the testing steps look good but additional changes are needed for this PR in the end as we're vendoring the pip version being used:

1. We set pip==9.02 in the dds-vendor Docker file so that will need to be bumped to the intended version (e.g., pip==20.2.4) here: https://github.com/plotly/dds-vendor/blob/a8bb3d389903e0db6331bad38476556db9aa21ad/Dockerfile#L5

2. We will then need to reference this vendored version by changing pip-9.0.2-py2.py3-none-any.whl to pip-20.2.4-py2.py3-none-any.whl here:

   heroku-buildpack-python/bin/steps/python

   Line 168 in e969daa

   /app/.heroku/python/bin/python "$PIP_DIR/get-pip.py" --no-index "$GET_PIP_PYPI_INDEX_URL/pip/pip-9.0.2-py2.py3-none-any.whl" "$GET_PIP_PYPI_INDEX_URL/setuptools/setuptools-39.0.1-py2.py3-none-any.whl" "$GET_PIP_PYPI_INDEX_URL/wheel/wheel-0.31.1-py2.py3-none-any.whl" &> /dev/null

3. Lastly, the version that will be used to compare pip against to trigger an upgrade can be updated (e.g., to 20.2.4) here:

   heroku-buildpack-python/bin/compile

   Line 67 in e969daa

   PIP_UPDATE="20.0.2"

Given the change to dds-vendor in 1), the image will need to be updated within the Replicated yaml for testing as well.

[vanastassiou]

@tarzzz please review.

[chriddyp]

/app/.heroku/python/bin/python "$PIP_DIR/get-pip.py" --no-index "$GET_PIP_PYPI_INDEX_URL/pip/pip-9.0.2-py2.py3-none-any.whl" "$GET_PIP_PYPI_INDEX_URL/setuptools/setuptools-39.0.1-py2.py3-none-any.whl" "$GET_PIP_PYPI_INDEX_URL/wheel/wheel-0.31.1-py2.py3-none-any.whl" &> /dev/null

Hey folks - I was reading through the heroku-buildpack-python CHANGELOG tonight and came across this: heroku/heroku-buildpack-python#1007. If we're updgrading the heroku buildpack too, then maybe the way we upgrade pip needs to change to use pip instead of get-pip.py? I don't know our own codebase at all, but just thought I'd share if helpful.

[vanastassiou]

@chriddyp Upstream does opt to use pip instead of get-pip.py, but I've been finding the sync with upstream rather complicated so was planning to split the sync out into a separate issue to ensure that pip was upgraded in a timely manner.

[tarzzz]

💃

[tarzzz]

@vanastassiou Can you please add a note in https://github.com/plotly/streambed/issues/15131 about Chris' comment so that it's not lost when we merge this PR.?