Release JetStream.Publisher 1.0.0-preview.7

[mtmk]

Preview release of JetStream.Publisher adding end-of-batch sentinel support to NatsJSBatchPublisher. Requires NATS Server 2.14+ for the new CloseAsync path.

• Add end-of-batch sentinel to Batch Publisher (Add end-of-batch sentinel to Batch Publisher #62)

[synadia-claude-reviewer]

Claude finished @mtmk's task in 1m 43s —— View job

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PR Review: Release JetStream.Publisher 1.0.0-preview.7

• Gather context: examine PR diff and relevant source files
• Review version change
• Review the batch publisher changes referenced in the PR
• Post review summary

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Summary

The PR itself is a single-line version bump (1.0.0-preview.6 → 1.0.0-preview.7). The substantive change is in the referenced commit (e19e066), which added CloseAsync — an end-of-batch (EOB) sentinel path to NatsJSBatchPublisher.

CloseAsync / EOB Implementation

Correctness looks good:

• The _sequence counter is intentionally not incremented for the EOB sentinel (line 279–281 in NatsJSBatchPublisher.cs), so Size stays consistent with ack.BatchSize. The expectedSize validation at line 325 (currentSeq - 1 for EOB) correctly checks this invariant.
• _closed = true is set inside CommitMsgInternalAsync's lock section (line 275) before any network I/O, so concurrent CloseAsync calls are safe: the loser sees _closed = true and throws NatsJSBatchClosedException.
• Empty-batch guard (_sequence == 0 || _batchSubject == null) is defensive and correct; the failed CloseAsync leaves the batch open for subsequent use as verified by the test at line 646–650.
• The Nats-Batch-Commit: eob header value is clearly documented in NatsJSBatchHeaders.BatchCommit.

One minor observation:

CloseAsync sends the sentinel on _batchSubject (the subject of message 1). For multi-subject batches the interface docs note this explicitly, but callers using entirely different subjects for every message might find it unexpected. This is a documentation/design trade-off rather than a bug, and the current docs cover it.

Test coverage is thorough: basic close, Size == ack.BatchSize consistency, empty-batch guard, close-after-close, and close-after-commit are all exercised with server-version guards for the 2.14+ EOB path.

Version Bump

version.txt change is correct and consistent with a preview release following the feature merge.

No blocking issues. The implementation is sound.