Thank you all for the comments so far. I would follow the process as suggested by Davor and others in this thread.
Ahmet On Tue, Jan 17, 2017 at 11:47 PM, Sergio Fernández <wik...@apache.org> wrote: > Hi > > On Tue, Jan 17, 2017 at 5:22 PM, Ahmet Altay <al...@google.com.invalid> > wrote: > > > > tl;dr: I would like to start a discussion about merging python-sdk branch > > to master branch. Python SDK is mature enough and merging it to master > will > > accelerate its development and adoption. > > > > Good point, Ahmet! > > I've following closed the development since it was imported in June. For > the prototypes I've implemented so far it works quite well; I guess we'd > just need to focus the next months in bringing more runners support. > > With a great effort from a lot of contributors(*), Python SDK [1] is now a > > mostly complete, tested, performant Python implementation of the Beam > > model. Since June, when we first started with Python SDK in Apache Beam > we > > have been continuously improving it. > > > > I wouldn't merge during the preparation of 0.5.0 release, but after that > could be a good time to merge back into master. > > > ** Python SDK currently supports: > > > > * Model: All main concepts are present (ParDo, GroupByKey, Windowing > etc.). > > * IO: There are extensible APIs for writing new bounded sources and > sinks. > > Implementations are provided for Text, Avro, BigQuery, and Datastore. > > * Runners: Python SDK has an extensible base runner module that allows > > building specific runners on top of it. The SDK comes with two pipeline > > runners: DirectRunner and DataflowRunner; and it is possible to add more. > > The existing runners are currently limited to bounded execution and > > otherwise equivalent to their Java SDK counterparts in functionality. > > > > What would the effort of porting, and maintaining, parallel versions of the > Java runners? I guess I'd need to dig deeper in the model, but this may > represent a major effort for the project, right? > It is somewhat higher for DirectRunner because DirectRunner also implements the code for execution. It is not that high for DataflowRunner because the base runner module has a lot of helpers with the right hooks for implementing a generic runner. I would _expect_ the experience in general would be similar to the latter. > > > > > * Testing: Python SDK implements ValidatesRunner test framework for > > implementing integration test for current and future runners. There is > unit > > test coverage for all modules, and a number of integrations test for > > validating existing runners. > > * Documentation and examples: Documentation work has started on Python > SDK. > > Beam Programming Guide page has been updated to include Python [2]. The > > code comes with many ready to use examples and we are in a good place to > > start documenting those on the website. > > > > ** We are not done yet, next on the roadmap we have: > > > > * Streaming: Both of the existing runners lack support for streaming > > execution, and currently there is work going on for adding streaming > > support to DirectRunner [3]. > > * Documentation: Filling the rest of the Beam documentations with Python > > SDK specific information and examples. > > * SDK consistency: Making Python SDK consistent with the Java SDK. We > have > > come a long way on this and have only a few items left [4]. > > * Beamifying: We have been working on removing Dataflow-specific > references > > both from the documentation and from the code. There is some work left, > and > > we are currently working on those as well [5]. > > > > ** Steps and implications of merging to master: > > > > * Master branch is merged to python-sdk branch at regular intervals and > the > > last merge was on 12/22. All the past merges were uneventful because > there > > is a minimal overlap in modified files between branches. Integrating > > python-sdk to master will similarly touch a small number of existing > files. > > > > * Python SDK is using the same tools for building and testing. It is > > already integrated with Maven, Jenkins and Travis. Specifically the > impact > > to the testing infrastructure would be: > > - There will be two additional test configurations in Travis. Since > Travis > > runs all configurations in parallel there should not be a noticeable > change > > in the Travis run time. > > - Jenkins pre-commit test will start running the Python SDK tests. It > will > > add an additional 5 minutes to the completion time of pre-commit test. > > Historically Python SDK tests were not flaky and did not cause any random > > failures. > > - Jenkins Python post-commit test is already separated from the other > > post-commit tests and will continue to exist. It would not change the > > testing time for any other test. > > > > * The release process needs to be updated to accommodate releasing Python > > artifacts. Python SDK would fit in the existing release schedule and > could > > be released along with the Java SDK. The additional steps would include: > > - Generating Python artifacts. This could be done with a single command > > using Maven today. > > - Publishing the artifacts to a central repository such as PyPI. > > > > I'm more than happy to help on this. We left on purpose some things open > when we added Maven support to the Python build. > That would be awesome. We can coordinate on that post-merge. > > > > > - Updating the release guide to reflect the changes above. > > > > * Users: There are existing users using the Python SDK. To give a rough > > estimate, a distribution of the Beam Python SDK had a total of 23K > > downloads in the past 6 months [6]. Some of those users are already > engaged > > with the community (e.g. [7]). There might be an increased amount > > engagement from the rest of them after the merge. > > > > Python 3 support is something we definitively need to look ahead. I'd try > to make the codebase compatible with both 2.7.x and 3.6.x, rather than > using other solutions like 2to3. > I agree with you. I think it makes more sense to make codebase compatible with both. As you mentioned Python 3 support is not a short-term goal in the roadmap, and we can discuss it more as we approach that. > > > Looking forward to hearing your thoughts and comments on “graduating” > > python-sdk to the master. > > > > Thank you, > > Ahmet > > > > (*) Python SDK branch currently has a diverse group of contributors. > > Regular contributors include Charles Chen, Chamikara Jayalath, María > García > > Herrero, Mark Liu, Pablo Estrada, Robert Bradshaw (Apache Beam PMC), > > Sourabh Bajaj, and Vikas Kedigehalli. We have also had contributions from > > Abdullah Bashir, Marco Buccini, Sergio Fernández, Seunghyun Lee, and > > Younghee Kwon. > > > > [1] https://github.com/apache/beam/tree/python-sdk/sdks/python > > [2] https://beam.apache.org/documentation/programming-guide/ > > [3] https://issues.apache.org/jira/browse/BEAM-1265 > > [4] > > https://issues.apache.org/jira/issues/?jql=status%20%3D%20Op > > en%20AND%20labels%20%3D%20sdk-consistency > > [5] https://issues.apache.org/jira/browse/BEAM-1218 > > [6] https://pypi.python.org/pypi/google-cloud-dataflow/json > > [7] https://issues.apache.org/jira/browse/BEAM-1251 > > > > > Great summary, Ahmet. Thanks. > > Cheers, > > -- > Sergio Fernández > Partner Technology Manager > Redlink GmbH > m: +43 6602747925 > e: sergio.fernan...@redlink.co > w: http://redlink.co >
