Skip to content

[836] xtable-spark-runtime: thin drop-in Spark bundle (Hudi 0.x)#843

Open
vinishjail97 wants to merge 8 commits into
apache:branch-0.4from
vinishjail97:836-spark-runtime-hudi0x
Open

[836] xtable-spark-runtime: thin drop-in Spark bundle (Hudi 0.x)#843
vinishjail97 wants to merge 8 commits into
apache:branch-0.4from
vinishjail97:836-spark-runtime-hudi0x

Conversation

@vinishjail97

@vinishjail97 vinishjail97 commented Jul 9, 2026

Copy link
Copy Markdown
Contributor

Ports xtable-spark-runtime onto the Hudi 0.x line (branch-0.4, Hudi 0.14 / Spark 3.4) — a thin, relocated Spark bundle that runs an incremental XTable sync in-job; engines are provided by the cluster, never bundled. Hudi-0.x counterpart of #838; part of the 0.4.0 on-ramp.

  • Module: xtable-spark-runtime (~3.7 MB) with XTableSparkSync spark-submit entry point; resilient ConversionTargetFactory ServiceLoader discovery so a subset of engines works when others are absent.
  • Hudi 0.14 specifics: no hudi-hadoop-common (1.x split); engine classpath uses the hudi-spark bundle so Avro model classes link on Avro 1.12 (Iceberg 1.9.2), plus hudi-java-client.
  • Testing: ITXTableSparkRuntimeBundle covers each direction across Hudi/Iceberg/Delta. It's SPARK_HOME-gated, so a dedicated Spark Runtime Bundle Validation workflow installs Spark 3.4.3, sets SPARK_HOME, and runs it (green); the standard CI build skips it.

Ports the xtable-spark-runtime packaging slice onto the Hudi 0.x line
(main-hudi-0x, Hudi 0.14 / Spark 3.4). New thin, relocated bundle that
runs an incremental XTable sync inside a Spark job; engines are provided
by the cluster, never bundled.

Module:
- xtable-spark-runtime_${scala.binary.version}: xtable-core compile;
  Spark/Hadoop and the engines (Hudi/Iceberg/Delta) provided. Curated
  shade allowlist (xtable modules + guava/protobuf/commons-cli relocated);
  avro/parquet/jackson NOT relocated (exchanged with the engines). Thin
  ~3.7 MB bundle.
- XTableSparkSync: standalone spark-submit entry point (Apache Commons CLI).
- XTableSyncService / TableSyncSpec: build an INCREMENTAL ConversionConfig
  and run ConversionController.sync; target metadata path = source data
  path (required by Hudi; Iceberg data lives under <basePath>/data).

Hudi 0.14 specifics (vs the Hudi 1.x variant on main):
- No hudi-hadoop-common (that split is 1.x); hudi-common provides FSUtils.
- Engine classpath uses the hudi-spark bundle (its regenerated Avro model
  classes link on Avro 1.12, which Iceberg 1.9.2 requires) plus
  hudi-java-client for the Hudi target's Java write client, with the raw
  hudi-common excluded so the bundle's clean DecimalWrapper wins.

ConversionTargetFactory: make ServiceLoader discovery resilient so a
subset of engines works when others are absent (warn + skip on
LinkageError/ServiceConfigurationError; name-based Delta-Kernel check).

ITXTableSparkRuntimeBundle: spark-submits the shaded jar for one case per
direction across Hudi, Iceberg and Delta (source and target), engines on
a flat classpath, asserting data-equivalence over comparable scalar
columns. Requires a Spark 3.4 SPARK_HOME; skipped otherwise.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Comment thread xtable-spark-runtime/pom.xml Outdated
Comment thread rfc/rfc-3/rfc-3.md
Comment thread rfc/rfc-3/rfc-3.md
Comment thread xtable-spark-runtime/pom.xml
Comment thread xtable-spark-runtime/pom.xml
Comment thread xtable-spark-runtime/pom.xml
Comment thread xtable-spark-runtime/src/main/java/org/apache/xtable/spark/XTableSyncService.java Outdated
vinishjail97 and others added 3 commits July 9, 2026 18:20
…sing, RFC)

Publish the shaded jar as the MAIN artifact with a dependency-reduced POM
(shadedArtifactAttached=false, createDependencyReducedPom=true), matching
iceberg-spark-runtime / hudi-spark-bundle. Resolving the coordinate via a
Maven dependency or --packages now yields the relocated bundle and pulls no
un-relocated transitive deps; --jars is equivalent. The thin main jar +
separate -bundle classifier (which re-introduced the cluster guava clash)
is gone. IT findBundleJar() now picks the shaded main jar.

Pass release/scripts/validate_shaded_license_coverage.sh (the existing
allowlist gate): the shade <includes> must equal the runtime dependency
tree, so jackson / scala-library / log4j-1.2-api - which every Spark
runtime supplies - are declared provided (dropped from the tree, kept off
the shaded jar) and excluded from the IT's flat engine classpath so Spark's
own copies win. avro/parquet stay on the flat classpath (the engine's newer
avro must win over Spark 3.4's).

Bundled-dependency licensing: add META-INF/LICENSE-bundled and
NOTICE-bundled (wired via IncludeResourceTransformer) attributing the only
bundled third-party - guava's closure (Apache-2.0) and commons-cli
(Apache-2.0), plus checker-qual (MIT). Remove the dead protobuf-java
allowlist entry and relocation: protobuf resolves as provided and was never
bundled.

RFC-3: scope v1 to the CLI (XTableSparkSync); mark the config-only
XTableSyncListener on-ramp (and XTableSparkConfig / PlanTargetResolver) as a
deferred follow-up. Fix the activation example to the shipped CLI and
document the required engine Avro version + flat-classpath placement.

XTableSyncService: normalize sourceFormat with Locale.ROOT.

Root pom: exclude the shade-generated dependency-reduced-pom.xml from
spotless (no license header; CI runs clean install).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Consolidate repeated rationale in the bundle pom (no functional change):
- Tell the hudi-common DecimalWrapper / Avro-1.8-1.9 story once (on the
  hudi-spark bundle dep); the hudi-java-client exclusion just points to it.
- State "engine Avro must win on a flat classpath" once (engine-classpath
  plugin); the avro dep and excludeGroupIds comments reference it.
- Explain jackson/scala-library are Spark-supplied once.
- Fix a stale "Spark 3.5" reference to Spark 3.4 (this is the Hudi 0.x line).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Add main-hudi-0x to the push and pull_request branch filters of both
workflows (same change as apache#841) so CI runs on PRs targeting the Hudi 0.x
release line, including this one. A pull_request workflow's branch filter
takes effect from the PR's own branch, so this makes CI fire on apache#843.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
@vinishjail97
vinishjail97 marked this pull request as ready for review July 10, 2026 01:29
…k-submit stdout off-thread

- ConversionTargetFactory: hasNext() resolves provider classes lazily and can
  throw ServiceConfigurationError too, so move it inside the existing
  ServiceConfigurationError|LinkageError guard alongside next().
- ITXTableSparkRuntimeBundle: drain spark-submit stdout on a background thread
  so a hung process is caught by waitFor(10min) instead of blocking forever on
  readOutput() reading until EOF.
main-hudi-0x was deleted and replaced by branch-0.4 (the 0.4.0 release line),
so update the push/pull_request branch filters accordingly.
…istro

ITXTableSparkRuntimeBundle spark-submits the shaded bundle jar and
self-skips unless SPARK_HOME is set, so the main CI never runs it. Add a
path-filtered workflow that installs a matching Spark 3.4 distribution
from the Apache archive, sets SPARK_HOME, and runs the failsafe IT.
…filter)

The workflow is intended to be a required status check on branch-0.4. A
required check whose workflow is skipped by a path filter never reports,
leaving PRs blocked on a pending check, so run it unconditionally on the
covered branches. The Spark distro is cached, so the added cost is the
reactor build plus the ~20s IT.

@vinothchandar vinothchandar left a comment

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Thanks @vinishjail97 ~ I think this will make life 10x better for users.

push:
branches:
- "main"
- "branch-0.4"

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I was a little confused at first to see the version number. But it seems you already cut the release branch

workflow_dispatch:

env:
SPARK_VERSION: "3.4.3"

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This cannot be 3.5 or something.?

Arrays.stream(cmd.getOptionValue(TARGETS).split(","))
.map(String::trim)
.filter(s -> !s.isEmpty())
.map(s -> s.toUpperCase(Locale.ROOT))

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The resolved target list is never validated to be non-empty. An input like --targets "," (or all-blank entries) passes through trim/filter and yields an empty targetFormats, so the sync silently produces no target tables and does nothing. Consider failing fast with a clear message when the resulting list is empty.

.dataPath(cmd.getOptionValue(DATA_PATH))
.namespace(namespace == null ? null : namespace.split("\\."))
.partitionSpec(cmd.getOptionValue(PARTITION_SPEC))
.sourceFormat(cmd.getOptionValue(SOURCE_FORMAT).toUpperCase(Locale.ROOT))

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

An unsupported --sourceFormat isn't rejected here; it surfaces only later in XTableSyncService.sourceProviderFor(...) as an UnsupportedOperationException, after the SparkSession has already been created via getOrCreate(). Consider validating the source format (and required args) up front in the CLI so an invalid value fails fast without spinning up Spark.

on:
push:
branches:
- "main"

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The Spark version is hardcoded to 3.4.3. Since this module targets the Hudi 0.x / Spark 3.4 line, that's reasonable, but consider parameterizing it (matrix or workflow input) or at least adding a comment explaining why 3.4.x is pinned, so the validation stays easy to bump. (A maintainer also raised this above.)

<description>
Thin, relocated, drop-in Spark bundle that runs incremental XTable metadata sync. v1 ships
the standalone spark-submit entry point (XTableSparkSync); the config-only, driver-side
QueryExecutionListener on-ramp is a planned follow-up (see rfc/rfc-3).

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

So right now, the sync needs to be manually invoked?

<scope>provided</scope>
</dependency>
<!--
XTable's Hudi TARGET writes via the Java client (HoodieJavaEngineContext), which the Spark

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

+1 . we should keep it this way, and publish the support matrix of what format versions works for source -> target? (could we add docs for that?)

Comment thread rfc/rfc-3/rfc-3.md
- @vinishjail97

## Approvers
- Anyone from the XTable community can approve/add feedback.

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

You can pencil me in

Comment thread rfc/rfc-3/rfc-3.md
is **deferred to a follow-up PR** — those classes are not in v1. The listener design is retained
below as the target so the entry point and config schema stay aligned.

### Activation — v1 (CLI entry point)

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Can we also document how to call this from code i.e from within pySpark or spark code? These could go into the quickstart as well. Can we revamp that

Comment thread rfc/rfc-3/rfc-3.md
## Approvers
- Anyone from the XTable community can approve/add feedback.

## Status

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

the rfc looks good, given the implementation is in the same PR as well, you can look at my comments on those

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

None yet

Projects

None yet

Development

Successfully merging this pull request may close these issues.

3 participants