Update e2e tests

[nikatza]

E2e tests update

Update tests to validate the full reconciliation pipeline from Kubernetes CRD to gNMI JSON output.

Rationale

Unit tests verify individual functions but miss the gaps between layers: CRD validation, controller logic, provider field mapping, and gNMI path construction. For example, a controller passing the wrong value to a provider.

The current e2e tests cover this but rely on Kind clusters with a full operator installation. This PR refactors both test modes to share the same testdata-driven approach:

• Envtest mode — runs without infrastructure using envtest + in-process gnmi-test-server. Tests run sequentially but complete in seconds.
• Cluster mode — runs against Kind with full operator installation. Validates RBAC, webhooks, metrics. Each test deploys its own gnmi-test-server pod in its own namespace.

Test Format

Each test is a txtar file in test/e2e/testdata/<provider>/:

-- state/preload --              # OPTIONAL: initial gNMI state
{"System": {"procsys-items": {"bootTime": "1700000000"}}}

-- Interface/lo0 --
apiVersion: networking.metal.ironcore.dev/v1alpha1
kind: Interface
spec:
  deviceRef:
    name: device                 # substituted at runtime
  ...

-- state/expect --
{"System": {"intf-items": ...}}

Resources are created sequentially, waiting for Configured (or Ready if the former does not exist) condition before proceeding. This handles dependencies between resources (e.g., BGPPeer requires BGP).

Note: The JSON stored in gnmi-test-server may differ from actual provider output. For example, NXOS DME_UNSET_PROPERTY_MARKER values are filtered out by the test server.

Usage

# Fast, no cluster required
make test-e2e-envtest PROVIDER=cisco-nxos-gnmi

# Full cluster mode (requires Kind)
make test-e2e PROVIDER=cisco-nxos-gnmi

Key Changes

• Unified TestEnvironment interface in testutil/ — both modes implement the same contract
• Cluster mode now deploys a gnmi-test-server pod per test for isolation
• Shared testdata discovery — both modes auto-discover test/e2e/testdata/<provider>/*.txt
• Added PreloadGNMIState() for setting initial device state before reconciliation
• Added state/preload txtar section for tests that need pre-existing gNMI state
• Add more samples

[github-actions]

Merging this branch will not change overall coverage

Impacted Packages	Coverage Δ	🤖
github.com/ironcore-dev/network-operator/internal/transport/gnmiext	90.21% (ø)
github.com/ironcore-dev/network-operator/test/e2e	0.00% (ø)
github.com/ironcore-dev/network-operator/test/e2e/testutil	0.00% (ø)
github.com/ironcore-dev/network-operator/test/gnmi	0.00% (ø)
github.com/ironcore-dev/network-operator/test/gnmi/testserver	0.00% (ø)

---

Coverage by file

Changed files (no unit tests)

Changed File	Coverage Δ	Total	Covered	Missed	🤖
github.com/ironcore-dev/network-operator/test/e2e/testutil/cluster.go	0.00% (ø)	0	0	0
github.com/ironcore-dev/network-operator/test/e2e/testutil/doc.go	0.00% (ø)	0	0	0
github.com/ironcore-dev/network-operator/test/e2e/testutil/envtest.go	0.00% (ø)	0	0	0
github.com/ironcore-dev/network-operator/test/e2e/testutil/helpers.go	0.00% (ø)	0	0	0
github.com/ironcore-dev/network-operator/test/e2e/testutil/provider.go	0.00% (ø)	0	0	0
github.com/ironcore-dev/network-operator/test/gnmi/main.go	0.00% (ø)	0	0	0
github.com/ironcore-dev/network-operator/test/gnmi/testserver/server.go	0.00% (ø)	0	0	0

Please note that the "Total", "Covered", and "Missed" counts above refer to code statements instead of lines of code. The value in brackets refers to the test coverage of that file in the old version of the code.

Changed unit test files

• github.com/ironcore-dev/network-operator/internal/transport/gnmiext/client_test.go
• github.com/ironcore-dev/network-operator/test/e2e/cluster_suite_test.go
• github.com/ironcore-dev/network-operator/test/e2e/cluster_test.go
• github.com/ironcore-dev/network-operator/test/e2e/e2e_test.go
• github.com/ironcore-dev/network-operator/test/e2e/envtest_suite_test.go
• github.com/ironcore-dev/network-operator/test/e2e/envtest_test.go
• github.com/ironcore-dev/network-operator/test/e2e/suite_test.go
• github.com/ironcore-dev/network-operator/test/e2e/util_test.go

[nikatza]

Closing this PR as it is replaced by smaller ones.