refactor(client): pin 1.7.0 shape with deterministic structural assertions

[Muawiya-contact]

test(client): pin 1.7.0 backend_metrics shape with deterministic structural assertions

Closes #326

---

What does this PR do?

Replaces the loose assertGreater(len(...), 1) check in test_metric.py with deterministic structural assertions based on the actual /metrics/backend response captured from a real HugeGraph server.

The problem

The old assertion only checked length — shape drift in the API response would pass silently without any test failure.

# Before — too loose
self.assertGreater(len(backend_metrics["hugegraph"]), 1)

The fix

# After — deterministic structural assertion
missing_keys = EXPECTED_BACKEND_SERVER_KEYS - set(server_entry.keys())
self.assertFalse(missing_keys, f"Missing expected keys: {missing_keys}")

What was verified

• Captured the actual /metrics/backend response from a real HugeGraph server
• Pinned EXPECTED_BACKEND_SERVER_KEYS from that real response
• Asserts backend, nodes, cluster_id, servers fields exist with correct types
• Asserts all expected rocksdb metric keys are present in the server entry

Test results

Server version	Result
HugeGraph 1.7.0 (Docker)	✅ PASSED
HugeGraph latest (Docker)	✅ PASSED

Both versions return identical shapes — one assertion covers both.

Files changed

Only one file touched: hugegraph-python-client/src/tests/api/test_metric.py

[Muawiya-contact]

@imbajin, any feedback please?

[Copilot]

Pull request overview

This PR tightens the python-client integration test for GET /metrics/backend by replacing a loose length-only assertion with deterministic structural assertions that pin the expected HugeGraph 1.7.0 backend_metrics response shape (and intended to remain compatible with newer versions).

Changes:

• Introduces a pinned set of expected metric keys (EXPECTED_BACKEND_SERVER_KEYS) for each backend server entry.
• Replaces the old conditional/len-based assertion with explicit structural checks for graph entry fields (backend, nodes, cluster_id, servers) and expected RocksDB metrics.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Muawiya-contact]

Hey @imbajin — all 13 CI checks are green and Copilot's review looks good too. Would love to get your eyes on this when you have a moment. Thanks!

[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 3 comments.

[Muawiya-contact]

@imbajin, Done ✅

[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

[Muawiya-contact]

@imbajin I have added now...

[imbajin]

Note we refact the test frame in #357

[Muawiya-contact]

Thanks for the heads-up @imbajin.

I checked #357 and understand the test framework has been refactored there. My intention in #342 was specifically to restore deterministic structural assertions for backend_metrics.

If there are any adjustments needed to align this PR with the new test framework in #357, I'd be happy to update it. Thanks for reviewing.

[imbajin]

just resolve the conflicts 🔢

[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

[imbajin]

One remaining portability issue: the test now pins RocksDB-specific backend metric fields in a python-client integration test. The graph-key concern is already covered by existing Copilot comments.

[Copilot]

Copilot encountered an error and was unable to review this pull request. You can try again by re-requesting a review.

[imbajin]

+1, LGTM. The current head addresses the previous graph-key selection and RocksDB portability concerns, and the client integration jobs pass against the HugeGraph 1.7.0 baseline.