GitHub user steveniemitz opened a pull request:
https://github.com/apache/beam/pull/3997
[BEAM-3061] Done notification for BigtableIO.write()
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---
This adds support for "done" notification in `BigtableIO.write()`. For
each bundle that is completely written, a single "Void" is output by the
PTransform. Doing so allows flows to effectively wait for all writes to finish.
This works well for batch flows (and I've been using for a few weeks now in
some large ones), but there is some limitation on the streaming side.
For streaming writes, all "done" notifications are output into the global
window, rather than the window(s?) that was(were) written in that bundle. I'm
not very familiar with the interactions of bundles, windows, and panes in the
streaming API, so I haven't tried to solve this at all, although for this IO
specifically it seems doable.
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/tc-dc/beam bigtable-done-notification
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/beam/pull/3997.patch
To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:
This closes #3997
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commit b6848d54c4eac2942abed6ce363aaa5ae3f2ba05
Author: steve <[email protected]>
Date: 2017-09-25T14:21:40Z
Done notification for BigtableIO
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---
