feat: Add custom metadata support for IPC messages and RecordBatch#361
Merged
Conversation
Decode and expose custom metadata from IPC message headers, propagating it through the reader to RecordBatch instances. This allows accessing per-batch metadata stored in Arrow IPC streams and files.
Extend RecordBatchWriter to support writing custom metadata to IPC
messages, similar to PyArrow's write_batch(batch, custom_metadata=...).
Changes:
- Update Message.from() to accept optional metadata parameter
- Update Message.encode() to serialize custom metadata to FlatBuffers
- Add customMetadata parameter to RecordBatchWriter.write()
- Add mergeMetadata() helper that combines batch.metadata with the
parameter (parameter takes precedence for duplicate keys)
- Add comprehensive integration tests for write/read round-trip
Usage:
writer.write(batch, new Map([['key', 'value']]));
trxcllnt
requested changes
Jan 15, 2026
trxcllnt
left a comment
trxcllnt
left a comment
Contributor
There was a problem hiding this comment.
Looks good so far, just a few questions about the writer API.
Contributor
Author
|
@trxcllnt I think this should be good to go, do you need any more changes? |
trxcllnt
approved these changes
Feb 20, 2026
trxcllnt
left a comment
trxcllnt
left a comment
Contributor
There was a problem hiding this comment.
Yeah, looks good to me!
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
What's Changed
Decode and expose custom metadata from IPC message headers, propagating it through the reader to RecordBatch instances. This allows accessing per-batch metadata stored in Arrow IPC streams and files.
Extend RecordBatchWriter to support writing custom metadata to IPC messages, similar to PyArrow's write_batch(batch, custom_metadata=...).
Changes:
parameter (parameter takes precedence for duplicate keys)
Usage:
writer.write(batch, new Map([['key', 'value']]));