Encode paneinfo with PaneInfoCoder.

[claudevdm]

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[shunping]

Just out of curiosity, what's wrong with not having a PaneInfoCoder. I see the issue #34826, but does FastPrimitiveCoder still work?

[claudevdm]

Just out of curiosity, what's wrong with not having a PaneInfoCoder. I see the issue #34826, but does FastPrimitiveCoder still work?

FastPrimitiveCoder ends up falling back to PickleCoder and much bigger encodings. PaneInfoCoder encodes it using 1 byte.

[shunping]

Just out of curiosity, what's wrong with not having a PaneInfoCoder. I see the issue #34826, but does FastPrimitiveCoder still work?

FastPrimitiveCoder ends up falling back to PickleCoder and much bigger encodings. PaneInfoCoder encodes it using 1 byte.

I don't get why we need to expose PaneInfoCoder because I don't think we want cx to use it (or mess with it). PaneInfoCoder should implicitly be part of WindowValueCoder according to runner api proto (

beam/model/pipeline/src/main/proto/org/apache/beam/model/pipeline/v1/beam_runner_api.proto

Line 938 in c9a0e90

// pane - The first byte of the pane info determines which type of

).

I may be missing some important piece of background in #34348, but regarding

beam/sdks/python/apache_beam/transforms/util.py

Line 955 in c9a0e90

return key, (value, timestamp, pane_info)

can we do the following?

return key, window.GlobalWindows.windowed_value(value, timestamp, pane_info)

In this case, the coder of this output will be KVCoder[KeyCoder, WindowedValueCoder[GlobalWindowCoder, ValueCoder]], instead of KVCoder[KeyCoder, TupleCoder[ValueCoder, TimeStampCoder, PaneInfoCoder]].