Add release process [skip ci]

Author: mbohlool

devel/release.md

@@ -0,0 +1,136 @@
+# Release process
+
+Release process of python client involve creating (or updating) a release
+branch, update release tags, create distribution packages and upload them to
+pip.
+
+## Change logs
+Make sure changes logs are up to date [here](https://github.com/kubernetes-incubator/client-python/blob/master/CHANGELOG.md).
+If they are not, follow commits added after last release and update/commit
+the change logs to master.
+
+## Release branch
+
+Release branch name should have release-x.x format. All minor and pre-releases
+should be on the same branch. To update an existing branch:
+
+```bash
+export RELEASE_BRANCH=release-x.x
+git checkout RELEASE_BRANCH
+git fetch upstream
+git pull upstream/master
+git push origin RELEASE_BRANCH
+```
+
+You may need to fix some conflicts. For auto-generated files, you can commit
+either version. They will be updated to the current version in the next step.
+
+## Sanity check generated client
+We need to make sure there is no API changes after running update client
+scripts. Such changes should be committed to master branch first. Run this
+command:
+
+```bash
+scripts/update-client.sh
+```
+
+And make sure there is no API change (version number changes should be fine
+as they will be updated in next step anyway). Do not commit any changes at
+this step and go back to master branch if there is any API changes.
+
+## Update release tags
+
+Release tags are in scripts/constants.py file. These are the constants you may
+need to update:
+
+CLIENT_VERSION: Client version should follow x.y.zDn where x,y,z are version
+numbers (integers) and D is one of "a" for alpha or "b" for beta and n is the
+pre-release number. For a final release, "Dn" part should be omitted. Examples:
+1.0.0a1, 2.0.1b2, 1.5.1
+SPEC_VERSION: This would be the kubernetes OpenAPI spec version. It should be
+deprecated after kubernetes/kubernetes#37055 takes effect.
+DEVELOPMENT_STATUS: Update it to one of the values of "Development Status"
+in [this list](https://pypi.python.org/pypi?%3Aaction=list_classifiers).
+
+after changing constants to proper versions, update the client using this
+command:
+
+```bash
+scripts/update-client.sh
+```
+
+and commit changes (should be only version number changes) to the release branch.
+Name the commit something like "Update version constants for XXX release".
+
+```bash
+git push upstream RELEASE_BRANCH
+```
+
+## Make distribution packages
+First make sure you are using a clean version of python. Use virtualenv and
+pyenv packages, make sure you are using python 2.7.12. I would normally do this
+on a clean machine:
+
+(install [pyenv](https://github.com/yyuu/pyenv#installation))
+(install [pip](https://pip.pypa.io/en/stable/installing/))
+(install [virtualenv](https://virtualenv.pypa.io/en/stable/installation/))
+
+```bash
+git clean -xdf
+pyenv install 2.7.12
+pyenv global 2.7.12
+virtualenv .release
+source .release/bin/activate
+python --version     # Make sure you get Python 2.7.12
+pip install twine
+```
+
+Now we need to create a "~/.pypirc" with this content:
+
+```
+[distutils]
+index-servers=pypi
+
+[pypi]
+repository = https://upload.pypi.org/legacy/
+username = kubernetes
+```
+
+TODO: we should be able to pass these parameters to twine directly. My first attempt failed.
+
+Now that the environment is ready, lets create distribution packages:
+
+```bash
+python setup.py sdist
+python setup.py bdist_wheel --universal
+ls dist/
+```
+
+You should see two files in dist folder. kubernetes*.whl and kubernetes*.tar.gz.
+
+TODO: We need a dry-run option an some way to test package upload process to pypi.
+
+If everything looks good, run this command to upload packages to pypi:
+
+```
+twine upload dist/*
+```
+
+## Create github release
+
+Create a gihub release by starting from
+[this page(https://github.com/kubernetes-incubator/client-python/releases).
+Click Deaft new release button. Name the tag the same as CLIENT_VERSION. Change
+the target branch to "release-x.y"
+
+
+ref: https://packaging.python.org/distributing/
+
+## Cleanup
+
+```bash
+deactivate
+rm -rf .release
+```
+
+TODO: Convert steps in this document to an (semi-) automated script.