[BEAM-3124] Make flatten explicit with portability

• Type: Improvement
• Status: Resolved
• Priority: P2
• Resolution: Done
• Fix Version/s: 2.4.0
• Component/s: beam-model
• Labels: portability
• Assignee: Daniel Oliveira
• Reporter: Daniel Oliveira
• Created: 31/Oct/17 18:08
• Updated: 16/May/20 13:46
• Resolved: 13/Mar/18 01:42

Description

Some adjustments need to be made to the way flattens are handled to the get them working for portability. Ideally flattens should be present in the execution graphs, there should be no DoFns with multiple inputs, and flattens should execute on either the system runners or SDK runners when appropriate.

Sub-Tasks

• Portable flattens in Java SDK Harness: Resolved
• Portable flattens in Python SDK Harness: Resolved
• Portable flattens in Dataflow Runner: Resolved