mosche opened a new pull request #16947:
URL: https://github.com/apache/beam/pull/16947


   @echauchot @aromanenko-dev Not really a PR (yet), I was just looking into 
understand usage of schemas vs coders better.
   The (most) interesting part here is probably `SdkPojoSchema` that works for 
all the generated AWS models in the SDK v2 (though, in some cases recursive 
types are used which obviously impose a challenge).
   
   I wasn't able to find a lot of good technical documentation (design 
decisions) for schemas in Beam, though definitely see the value over low level 
coders! It seems to make sense to bother users as little as possible with 
coders and [not expose these on any public 
API](https://docs.google.com/document/d/1V2FkGGunVgvLwi1dKHr-7mtDuwYjTuvuESV_oPzVnfQ/edit?resourcekey=0-KvfQq-5iCcMlu3f3MFJ-GQ#heading=h.xl97lw3dyot7)
 (M11). Currently coders are all over the place for AWS IOs, with this it seems 
feasible to drop them (or deprecate).
   
   Though, I was wondering a couple of things:
   - Looks like I cannot register a provider for an interface (`SdkPojo`), that 
means I have to "announce" it globally using an auto service.
   - Is there a way a Sink/ WriteIO can set the coder for it's input like that 
can be done for a Source on the output? Looks like it's only possible to 
register such a coder globally, regardless if that sink is used or not.
   - I noticed that a RowCoder cannot be automatically inferred for a row 
despite every row carrying its schema. That makes sense given runners may use 
the schema ahead of time for query planning. But it made me wonder if there's 
any relationship between the schema of the row coder and the runtime schema 
enforced... 
   
   If you have any good resources on the topic, I'd be happy to hear ...
   
   
   
   
   
   
   
   ------------------------
   
   Thank you for your contribution! Follow this checklist to help us 
incorporate your contribution quickly and easily:
   
    - [ ] [**Choose 
reviewer(s)**](https://beam.apache.org/contribute/#make-your-change) and 
mention them in a comment (`R: @username`).
    - [ ] Format the pull request title like `[BEAM-XXX] Fixes bug in 
ApproximateQuantiles`, where you replace `BEAM-XXX` with the appropriate JIRA 
issue, if applicable. This will automatically link the pull request to the 
issue.
    - [ ] Update `CHANGES.md` with noteworthy changes.
    - [ ] If this contribution is large, please file an Apache [Individual 
Contributor License Agreement](https://www.apache.org/licenses/icla.pdf).
   
   See the [Contributor Guide](https://beam.apache.org/contribute) for more 
tips on [how to make review process 
smoother](https://beam.apache.org/contribute/#make-reviewers-job-easier).
   
   To check the build health, please visit 
[https://github.com/apache/beam/blob/master/.test-infra/BUILD_STATUS.md](https://github.com/apache/beam/blob/master/.test-infra/BUILD_STATUS.md)
   
   GitHub Actions Tests Status (on master branch)
   
------------------------------------------------------------------------------------------------
   [![Build python source distribution and 
wheels](https://github.com/apache/beam/workflows/Build%20python%20source%20distribution%20and%20wheels/badge.svg?branch=master&event=schedule)](https://github.com/apache/beam/actions?query=workflow%3A%22Build+python+source+distribution+and+wheels%22+branch%3Amaster+event%3Aschedule)
   [![Python 
tests](https://github.com/apache/beam/workflows/Python%20tests/badge.svg?branch=master&event=schedule)](https://github.com/apache/beam/actions?query=workflow%3A%22Python+Tests%22+branch%3Amaster+event%3Aschedule)
   [![Java 
tests](https://github.com/apache/beam/workflows/Java%20Tests/badge.svg?branch=master&event=schedule)](https://github.com/apache/beam/actions?query=workflow%3A%22Java+Tests%22+branch%3Amaster+event%3Aschedule)
   
   See [CI.md](https://github.com/apache/beam/blob/master/CI.md) for more 
information about GitHub Actions CI.
   


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: [email protected]

For queries about this service, please contact Infrastructure at:
[email protected]


Reply via email to