Files
cozystack/hack/e2e-chainsaw
Timofei Larkin 95ece888ba feat(kafka): add topic-data backup/restore example and e2e roundtrip (#3580)
## What this PR does

Adds a worked backup/restore example for a Cozystack-managed `Kafka`
application's **topic data**, built on the generic `Job` backup strategy
— the same pattern as `examples/backups/nats`, with no purpose-built
backup image. A stock Strimzi Kafka image (the `kafka-*.sh` CLI plus
`bash`, `curl` and `tar`) runs one shell script that branches on `{{
.Mode }}`: on backup it freezes each partition's end offset and drains
`[begin, end)` to a tarball it `PUT`s to S3; on restore it `GET`s the
tarball, recreates the topics with their original partition count and
replication factor, and replays every partition file. S3 access is `curl
--aws-sigv4`, verified against the endpoint's CA projected from the
`<app>-backup-s3` Secret, so no extra client image is needed.

The consistency model is a frozen-end-offset cut: `kafka-get-offsets
--time -1` is read once per partition at backup start and the consumer
drains only up to that offset, so anything produced during the run is
excluded and every partition of a topic is captured as of the same
instant — a cut by log position, independent of record timestamps.

This is deliberately a DATA-only backup. Topic configs, ACLs, SCRAM
users and **consumer-group offsets** are not captured, and re-produced
records receive fresh offsets — the README spells out the scope and
points at a volume-snapshot strategy for a faithful, offset-preserving
backup. Keyed records reproduce into their original partition because
the topic is recreated with the same partition count and the default
(murmur2) partitioner is deterministic.

The script fails closed rather than reporting a partial backup or a
lossy restore as success: it refuses an offset listing short of the
topic's partition count, a drain short of `end - begin`, a `topics`
value with a duplicate or a name outside Kafka's charset, a manifest
that disagrees with the data files, a target topic that already holds
records (checked before the replay, so a retried Pod cannot append a
second copy), a pre-existing topic with a different partition count or
replication factor, a replication factor below the target's effective
`min.insync.replicas`, and a post-replay count that does not match the
manifest. Each topic's replication factor is recorded in the manifest
and restored as captured; the `replicationFactor` BackupClass parameter
overrides it for restoring into a smaller cluster.

Also adds a `kafka-2-backup-roundtrip` Chainsaw test to
`hack/e2e-chainsaw/kafka`, which drives the example `run-all.sh` as its
harness (Bucket → two-broker source Kafka with a seeded 3-partition,
2-replica topic plus a decoy topic that the demo topic matches as a
regex but not as a literal → BackupJob → in-place restore with count,
content and replication-factor assertions → a second RestoreJob into the
populated topic that must be refused with the topic untouched →
two-broker target Kafka + to-copy restore + verify), mirroring
`mariadb-2-backup-roundtrip`. Two brokers, not one, because that is the
shape on which the chart sets `min.insync.replicas: 2` and a restore
with the wrong replication factor cannot land a record. It resolves the
Kafka image from the running operator so the backup Pod reuses the image
already cached on the nodes.

The strategy script itself is pinned by
`hack/kafka-topic-backup-strategy.bats`, on the shape of
`hack/kafka-backup-script.bats`: it renders the strategy through a stub
`kubectl` exactly as step 01 applies it, lifts the container body out,
and executes it against stubbed `kafka-*.sh`, a stubbed `curl` and a
directory standing in for S3, with fault injection for the broker
behaviours the guards exist for. Fourteen cases, one per guard; removing
the partition-listing guard reddens one of them.

Verified: `chainsaw/kafka-2-backup-roundtrip` passed in this PR's CI on
the two-broker shape (record count, byte-identical content dump and
replication factor 2 asserted after both restores, the refused
RestoreJob settled Failed with the topic untouched);
`hack/kafka-topic-backup-strategy.bats` passes under both
`hack/cozytest.sh` and bats.

Files:

- `examples/backups/kafka/` — 14 files (`00-helpers.sh`, `01`..`07`,
`run-all.sh`, `cleanup.sh`, `README.md`, `90`/`91`/`92` scenario
walk-throughs).
- `hack/kafka-topic-backup-strategy.bats` — hermetic test of the
strategy script.
- `hack/e2e-chainsaw/kafka/chainsaw-test.yaml` — new
`kafka-2-backup-roundtrip` Test appended.
- `hack/backup-access-preflight.bats` — the kafka example and Test join
the S3-preflight roster.
- `hack/select-e2e.sh`, `hack/e2e-chainsaw/.chainsaw.yaml` —
comment-only: their enumerations of preflight-gated suites are replaced
by a pointer.
- `.gitignore` — the example's `.source-dump.txt` snapshot.

No package sources (`values.yaml`, `values.schema.json`, `Chart.yaml`,
package `README.md`) are touched, so `make generate` produces no diff.

### Screenshots

N/A — no UI changes.

### Downstream repositories

Walked the trigger map in `docs/agents/contributing.md` file-by-file
against the diff. The change adds example scripts under
`examples/backups/kafka`, one unit test under `hack/`, and appends one
Chainsaw Test to an existing file under `hack/e2e-chainsaw/kafka` — it
adds no package under `packages/apps` or `packages/extra`, changes no
CRD, no `ApplicationDefinition`, no `values.schema.json`, no
platform/installer values, no `hack/*.mk` anchor or make-target
behaviour, and no node prerequisites in `hack/e2e-prepare-cluster.bats`.
None of the downstream triggers match.

- [x] No downstream repository is affected by this change
- [ ] [cozystack/website](https://github.com/cozystack/website) -
follow-up:
- [ ]
[cozystack/terraform-provider-cozystack](https://github.com/cozystack/terraform-provider-cozystack)
- follow-up:
- [ ]
[cozystack/ansible-cozystack](https://github.com/cozystack/ansible-cozystack)
- follow-up:
- [ ] [cozystack/ccp](https://github.com/cozystack/ccp) - follow-up:
- [ ] [cozystack/talm](https://github.com/cozystack/talm) - follow-up:
- [ ] [cozystack/cozyhr](https://github.com/cozystack/cozyhr) -
follow-up:
- [ ] [cozystack/cozy-proxy](https://github.com/cozystack/cozy-proxy) -
follow-up:
- [ ]
[cozystack/cozystack-telemetry-server](https://github.com/cozystack/cozystack-telemetry-server)
- follow-up:
- [ ]
[cozystack/external-apps-example](https://github.com/cozystack/external-apps-example)
- follow-up:
- [ ] [cozystack/examples](https://github.com/cozystack/examples) -
follow-up:

### Release note

```release-note
feat(kafka): add a topic-data backup/restore example and e2e round-trip on the generic Job backup strategy (data-only: topic records with a frozen-end-offset consistency cut and partition-preserving replay; consumer offsets, topic configs, ACLs and users are out of scope)
```
2026-09-24 13:00:15 +04:00
..

Chainsaw E2E tests

The Cozystack E2E app suite, written for Kyverno Chainsaw — a declarative, Kubernetes-native E2E test framework (CNCF, part of the Kyverno project; successor to KUTTL).

This directory replaces the per-app BATS suite that used to live in hack/e2e-apps/*.bats. The CI e2e job runs chainsaw test hack/e2e-chainsaw/ after make install-cozystack; cluster bootstrap (hack/e2e-prepare-cluster.bats, hack/e2e-install-cozystack.bats) and the OpenAPI checks (hack/e2e-test-openapi.bats) remain BATS.

Layout

hack/e2e-chainsaw/
├── .chainsaw.yaml          # global Configuration (namespace, timeouts, JUnit report)
├── _lib/                   # shell reused by the script-heavy suites
│   ├── run-kubernetes.sh   #   tenant Kubernetes bringup + LB/NFS/ouroboros checks
│   └── remediation-guard.sh
├── <app>/
│   ├── chainsaw-test.yaml  # one or more Test definitions
│   └── <app>.yaml          # the manifests the test applies
└── ...

Suites: postgres, bucket, mariadb, mongodb, redis, valkey, qdrant, clickhouse, kafka, rabbitmq, etcd, openbao, harbor, foundationdb, external-dns, kuberture, vminstance, gateway, opensearch, kubernetes-latest, kubernetes-previous, securitygroup.

What Chainsaw buys over the BATS suite

  • Readable tests — a list of resources and expected states, not shell control flow. The timeout N sh -ec "until kubectl get ..." + kubectl wait pair that appeared ~100 times collapses into a single assert that polls existence and state together.
  • Distinguishable failure modes — "object never created", "created but never ready", and "wrong status" all surface as a structured diff instead of an opaque shell timeout.
  • Automatic diagnostics — catch blocks dump events, describe, and pod logs on any failure (the BATS suite only did this in harbor.bats, by hand).
  • Automatic cleanup — resources Chainsaw applied are deleted (and waited on) in reverse order; finally covers operator-created leftovers.
  • CI-ready output — a JUnit chainsaw-report.xml is emitted for the test summary.

Test anatomy

Each suite is a directory with a chainsaw-test.yaml (one or more Test docs) plus the manifests it applies. A step has try (operations: apply, assert, error, script, delete, …), optional catch (diagnostics on failure), and optional finally (teardown regardless of outcome).

Declarative suites assert on status.conditions and concrete fields. Inherently imperative suites keep their logic in script steps:

  • openbao — bao operator init/unseal via kubectl exec.
  • kuberture — jq on Service annotations + external-dns split-horizon log assertions.
  • gateway — admission-rejection cases that need kubectl --as impersonation or error-message greps; the tenant apex is read from the namespace namespace.cozystack.io/host label at runtime so they pass on any host.
  • kubernetes-latest/previous — wrap _lib/run-kubernetes.sh (Kamaji bringup, port-forward, LB/NFS/ouroboros). The script cds to the repo root (the test dir is hack/e2e-chainsaw/<suite>, so repo root is ../../..).

Conventions / gotchas (Chainsaw v0.2.15)

  • Condition asserts use the filter-as-list form, not the documented [0] index:
    status:
      (conditions[?type == 'Ready']):
      - status: "True"
    
    The (conditions[?type == 'Ready'])[0]: {status: "True"} idiom fails with "field not found in the input object".
  • A reading of a failure diff: the "actual" side is a projection onto the expected fields — status: {} means the JMESPath expression failed, not that status is empty. Read the error line above the diff first.
  • error with a bare resource ref (name only) asserts the resource does not exist (used for "PVC reclaimed", "no backup schedule", "child has no Gateway HR").
  • script runs in the test directory with $NAMESPACE set to the config namespace (tenant-test).

Running locally

Requires a cluster with Cozystack installed and a tenant-test namespace (the environment hack/e2e-install-cozystack.bats produces). bucket additionally needs mc and nc on the host; kuberture/openbao/harbor need jq.

# install chainsaw
go install github.com/kyverno/chainsaw@latest   # or: brew install kyverno/chainsaw/chainsaw

# run all suites (config picked up from .chainsaw.yaml)
cd hack/e2e-chainsaw
chainsaw test

# run a single suite
chainsaw test postgres/

kubernetes-latest/kubernetes-previous each bring up a full tenant Kubernetes cluster (~25 min, real worker nodes) and vminstance boots a nested VM — expect a long run for the full set.

CI integration

The e2e job in .github/workflows/pull-requests.yaml runs make -C packages/core/testing test-chainsaw (which execs chainsaw test hack/e2e-chainsaw/ inside the e2e sandbox) and uploads chainsaw-report.xml. The sandbox image (packages/core/testing/images/e2e-sandbox/Dockerfile) ships the chainsaw binary alongside kubectl/helm/mc/jq/nc.