bundle/fuzz: add create-payload parity fuzz test for terraform vs direct#5686
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radakam wants to merge 8 commits into
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bundle/fuzz: add create-payload parity fuzz test for terraform vs direct#5686radakam wants to merge 8 commits into
radakam wants to merge 8 commits into
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Implements the first technique from DECO-25361: generate random job
configs and check for differences in the create payload between the
terraform and direct deploy engines.
Both engines run the same `bundle deploy` pipeline in-process (via
testcli) against a testserver, differing only in DATABRICKS_BUNDLE_ENGINE,
and the POST /api/2.2/jobs/create body each sends is captured and diffed.
Because only the engine differs, shared mutators cancel out and any
remaining diff is a genuine engine divergence.
The fuzzer already surfaced two real (benign) divergences, documented in
DefaultIgnorePaths:
- num_workers: 0 is sent explicitly by terraform but dropped by direct
(omitempty).
- the terraform provider strips the deprecated spark conf
"spark.databricks.delta.preview.enabled"; direct forwards it.
Run with: go test ./bundle/fuzz -run TestJobCreateParity
(FUZZ_SEEDS overrides the seed count; auto-skips when terraform is not
provisioned via acceptance/install_terraform.py).
…ignore Address golangci-lint failures (intrange loops, strconv.FormatBool over fmt.Sprintf) and tighten the create-payload ignore list: drop the dead job_clusters num_workers entry (those are at parity) and document the task-level num_workers divergence as a real CLI gap to fix separately.
Collaborator
Integration test reportCommit: e596815
20 interesting tests: 13 SKIP, 7 KNOWN
Top 4 slowest tests (at least 2 minutes):
|
- Add a `test-fuzz` task and a nightly CI job that provisions terraform and runs the create-payload parity tests. They previously always skipped because terraform was never provisioned in the test path. - Ignore repo-root build/ so the provisioned terraform binary and provider mirror are not accidentally committed. - Skip cleanly when build/ is only partially provisioned (missing provider mirror or .terraformrc) instead of failing mid-deploy. - Document that the harness covers jobs only for now (DECO-25361).
Make the create-payload parity fuzz suite explore new configs over time and be reproducible from a reported seed: - FUZZ_SEED (comma-separated) runs exactly those seeds, overriding the range, so a reported divergence reproduces with one command. The failure message now prints this knob. - FUZZ_SEED_OFFSET shifts the deterministic window; push.yml derives it from GITHUB_RUN_NUMBER so each nightly run checks seeds it has never tested before instead of re-checking a fixed set. Windows are non-overlapping because the run number is unique and monotonic. - Guard FUZZ_SEEDS > 0 so a negative value no longer panics make() and zero no longer passes as a no-op. - Drop the test-fuzz Task sources fingerprint: the seeds depend on env vars Task can't see, so skipping on an unchanged checksum would silently no-op a repro run or a shifted window. - Keep the nightly window modest (25); exploration comes from rotation, not size, and it can be raised once nightly timings are known.
The terraform provider force-sends num_workers: 0 for a single-node new_cluster (no autoscale) on both job_clusters and task-level clusters, but JobClustersFixups only applied initializeNumWorkers to job_clusters. The direct engine therefore omitted num_workers on task clusters, so the two engines produced divergent create payloads. This divergence was surfaced by the bundle/fuzz parity harness. Apply initializeNumWorkers to task new_cluster too so the direct engine matches terraform, and drop the now-obsolete tasks[*].new_cluster.num_workers entry from the fuzz DefaultIgnorePaths.
The nightly test-fuzz job is intentionally excluded from test-result, so a failure was only visible in the Actions tab. Add a failure step that opens (or comments on) a single deduped GitHub issue with a one-command repro. Also correct the jobsCreatePath comment: a different API version shows up as a capture failure (the testserver registers only this route, so a mismatched version 404s and the deploy fails), not as a payload diff.
…ion test Rename the capture/deploy/recorder helpers to *_test.go so the parity harness compiles only under `go test` instead of into the package's regular build, and add a committed regression test (cluster_fixups_test.go) covering the single-node task-cluster num_workers force-send fix so the divergence is guarded at PR time, not just in the nightly suite.
…ting Move the remaining generator/diff/rand implementation into _test.go files (keeping only a doc.go for the package comment) so nothing in the harness compiles into the regular build, since no product code imports it. Distinguish deploy/capture failures from create-payload divergences in checkJobParity: skip when neither engine deploys the generated config, fail distinctly when exactly one engine accepts it (an acceptance divergence, not a payload diff), and only diff payloads when both deploys succeed. This keeps nightly triage from misdirecting a deploy failure into regressionSeeds. Also document the unique-identity-key assumption in diffKeyedSlice.
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Changes
Adds a fuzz-testing harness (
bundle/fuzz) that verifies theterraformanddirectdeploy engines produce equivalent job create payloads from the same bundle config — the first technique from DECO-25361.generate.go/rand.go— seeded, reproducible randomresources.Jobgenerator (math/rand/v2PCG). Produces deploy-safe configs across a wide field surface: schedules/triggers/continuous, email & webhook notifications, health rules, git sources, job clusters, and tasks (notebook, spark-python, python-wheel, condition) with retries, libraries, and richnew_clusterspecs.capture.go/capture_deploy.go— runs a realbundle deployfor each engine against an in-processtestserverand captures thePOST /api/2.2/jobs/createbody. Both engines go through the identical mutator pipeline, so shared transformations cancel out in the diff. Terraform is auto-skipped when not provisioned (RequireTerraform).compare.go— JSON payload diff (numeric-aware viaUseNumber, bracket-quoted paths for dotted map keys likespark_confentries) with a small, justifiedDefaultIgnorePaths.fuzz_test.go— seed-driven property test (TestJobCreateParity,FUZZ_SEEDSoverride) plus a nativeFuzzJobCreateParitytarget for deep ad-hoc runs.Two divergences surfaced by the fuzzer:
tasks[*].new_cluster.num_workers(single-node task cluster) — terraform sendsnum_workers: 0, direct omits it. This is a real, currently-unhandled gap:JobClustersFixups.initializeNumWorkersforce-sendsnum_workersforjob_clustersbut is not applied to task-levelnew_cluster. The knownjob_clusterscase is already at parity (verified — no ignore needed). Ignored here with a comment; the product fix tocluster_fixups.gowill follow in a separate PR so this stays purely about the fuzz harness.spark_conf["spark.databricks.delta.preview.enabled"]— terraform's provider strips this key; direct forwards it. Backend ignores it either way; benign provider-side filter, ignored.Why
We want confidence that the
directengine is behaviorally equivalent toterraformbefore it becomes the default. Hand-written acceptance tests only cover known shapes; randomized generation surfaces divergences in field combinations no one thought to test — as proven by the task-levelnum_workersgap above.Tests
go test ./bundle/fuzz/passes (terraform-backed; ~50s).task lint-q→ 0 issues.python3 acceptance/install_terraform.py --targetdir build.