[BEAM-4150] Standardize use of PCollection coder proto attribute

• Type: Task
• Status: Resolved
• Priority: P2
• Resolution: Fixed
• Fix Version/s: 2.20.0
• Component/s: beam-model
• Assignee: Luke Cwik
• Reporter: Robert Bradshaw
• Created: 20/Apr/18 19:30
• Updated: 16/May/20 14:10
• Resolved: 04/Feb/20 19:47

Description

In some places it's expected to be a WindowedCoder, in others the raw ElementCoder. We should use the same convention (decided in discussion to be the raw ElementCoder) everywhere. The WindowCoder can be pulled out of the attached windowing strategy, and the input/output ports should specify the encoding directly rather than read the adjacent PCollection coder fields. 

Issue Links

• duplicates: BEAM-5415 [beam_PostCommit_Python_Verify] test times out with "Missing required coder_id" messages in Dataflow job logs.
• links to: GitHub Pull Request #4867
• links to: GitHub Pull Request #5700
• links to: GitHub Pull Request #7217
• links to: GitHub Pull Request #8533
• links to: GitHub Pull Request #10755
• links to: GitHub Pull Request #11222