Adds Python client suppport for Elasticsearch 7.5.1

[viglia]

Python client for Elasticsearch 7.5.1

[honzakral]

Please do not include the data_frame_transform_deprecated.py file - it contains deprecated API and is not even correct python, nor is it tied in to the rest of the client.

Also please do not exactly copy the ES version - there is no feasible way to keep that in sync as we wouldn't be able to release potential bugfix release of elasticsearch-py it is therefore better to just keep the major number in sync, at most major and minor.

Thank you

[viglia]

@honzakral , thanks for the feedback.

When you say "please do not exactly copy the ES version" do you mean in the setup.py and __init__.py or that I shouldn't generate from tag linking to patch version.
Should I generate from 7.5.0 instead of 7.5.1 ?

[honzakral]

yes, __init__.py, setup.py, and Changelog.rst version.

Leave it as 7.5.0 or ideally 7.2.0 which is the next version in the line of python versions

Always generate the API from the latest ES release in the proper major release, so 7.5.1 is correct choice there

[viglia]

@philkra please can you clarify and give me a feedback? I've been told to skip [7.2...7.4] and jump to 7.5.1.

[honzakral]

If you wish to stick to the version, go ahead, but I don't like committing to something that is not sustainable - if we have to do a bugfix release afte 7.5.1 we will have to release 7.5.2 when then Elasticsearch releases 7.5.2 we will be out of sync and there is nothing we can do. At that point I prefer to be explicit about the (possible) divergence. But up to @philkra of course

[philkra]

@viglia , please use 7.5.0. @honzakral explained our motives perfectly, we "only" follow up to the major.minor of Elasticsearch, giving us room to provide fixes in patch versions if necessary. Thanks @honzakral and @viglia for tackling 7.5.0.

[viglia]

@honzakral @philkra ok, perfect. Then if everyone is fine with this I will close this PR and regenerate pointing to ES 7.5.0 and create a new PR

[honzakral]

You should keep using 7.5.1 version of elasticsearch, just the version of elasticsearch-py should be 7.5.0

[philkra]

thank you @honzakral . That's the way to go @viglia .