singhpk234 commented on code in PR #1285: URL: https://github.com/apache/polaris/pull/1285#discussion_r2138530864
########## service/common/src/main/java/org/apache/polaris/service/catalog/iceberg/CatalogHandlerUtils.java: ########## @@ -433,39 +450,203 @@ protected TableMetadata commit(TableOperations ops, UpdateTableRequest request) 2.0 /* exponential */) .onlyRetryOn(CommitFailedException.class) .run( - taskOps -> { + (taskOps) -> { TableMetadata base = isRetry.get() ? taskOps.refresh() : taskOps.current(); - isRetry.set(true); - // validate requirements + TableMetadata.Builder metadataBuilder = TableMetadata.buildFrom(base); + TableMetadata newBase = base; try { - request.requirements().forEach(requirement -> requirement.validate(base)); + request.requirements().forEach((requirement) -> requirement.validate(base)); } catch (CommitFailedException e) { - // wrap and rethrow outside of tasks to avoid unnecessary retry - throw new ValidationFailureException(e); + if (!isRollbackCompactionEnabled()) { + throw new ValidationFailureException(e); + } + UpdateRequirement.AssertRefSnapshotID assertRefSnapshotId = + findAssertRefSnapshotID(request); + MetadataUpdate.SetSnapshotRef setSnapshotRef = findSetSnapshotRefUpdate(request); + + if (assertRefSnapshotId == null || setSnapshotRef == null) { + // This implies the request was not trying to add a snapshot. + throw new ValidationFailureException(e); + } + + // snapshot-id the client expects the table current_snapshot_id + long expectedCurrentSnapshotId = assertRefSnapshotId.snapshotId(); + + MetadataUpdate.AddSnapshot snapshotToBeAdded = findAddSnapshotUpdate(request); + if (snapshotToBeAdded == null) { + // Re-throw if, there's no snapshot data to be added. + throw new ValidationFailureException(e); + } + + List<MetadataUpdate> metadataUpdates = + generateUpdatesToRemoveNoopSnapshot( + base, + expectedCurrentSnapshotId, + setSnapshotRef.name(), + snapshotToBeAdded.snapshot().sequenceNumber()); + + if (metadataUpdates == null || metadataUpdates.isEmpty()) { + // Nothing can be done as this implies that there were not all + // No-op snapshots (REPLACE) between expectedCurrentSnapshotId and + // currentSnapshotId. hence re-throw the exception caught. + throw new ValidationFailureException(e); + } + // Set back the ref we wanted to set, back to the snapshot-id + // the client is expecting the table to be at. + metadataBuilder.setBranchSnapshot( + expectedCurrentSnapshotId, setSnapshotRef.name()); + + // apply the remove snapshots update in the current metadata. + // NOTE: we need to setRef to expectedCurrentSnapshotId first and then apply + // remove, as otherwise the remove will drop the reference. + // NOTE: we can skip removing the now orphan base. Its not a hard requirement. + // just something good to do, and not leave for Remove Orphans. + // Ref rolled back update correctly to snapshot to be committed parent now. + metadataUpdates.forEach((update -> update.applyTo(metadataBuilder))); + newBase = setAppropriateLastSeqNumber(metadataBuilder.build()); } - - // apply changes - TableMetadata.Builder metadataBuilder = TableMetadata.buildFrom(base); - request.updates().forEach(update -> update.applyTo(metadataBuilder)); - - TableMetadata updated = metadataBuilder.build(); - if (updated.changes().isEmpty()) { - // do not commit if the metadata has not changed - return; + // double check if the requirements passes now. + try { + TableMetadata baseWithRemovedSnaps = newBase; + request + .requirements() + .forEach((requirement) -> requirement.validate(baseWithRemovedSnaps)); + } catch (CommitFailedException e) { + throw new ValidationFailureException(e); } - // commit + TableMetadata.Builder newMetadataBuilder = TableMetadata.buildFrom(newBase); + request.updates().forEach((update) -> update.applyTo(newMetadataBuilder)); + TableMetadata updated = newMetadataBuilder.build(); + // always commit this taskOps.commit(base, updated); }); - } catch (ValidationFailureException e) { throw e.wrapped(); } return ops.current(); } + private UpdateRequirement.AssertRefSnapshotID findAssertRefSnapshotID( + UpdateTableRequest request) { + UpdateRequirement.AssertRefSnapshotID assertRefSnapshotID = null; + int total = 0; + for (UpdateRequirement requirement : request.requirements()) { + if (requirement instanceof UpdateRequirement.AssertRefSnapshotID) { + ++total; + assertRefSnapshotID = (UpdateRequirement.AssertRefSnapshotID) requirement; + } + } + + // if > 1 assertion for refs, then it's not safe to roll back, make this Noop. + return total != 1 ? null : assertRefSnapshotID; Review Comment: yes, wanted to return`null` to mark its not valid. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@polaris.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org