fix(observability-tracing-openobserve): return empty result when stream not yet created

[mvanhorn]

Purpose

Moves the OpenObserve empty-stream handling from the observer interface (openchoreo/openchoreo) into this adapter, per @akila-i's review feedback on openchoreo/openchoreo#3439. The observer interface stays adapter-agnostic; OpenObserve-specific codes (20002 = "stream not found") live in the adapter that actually knows them.

Refs:

• Traces API returns 500 when no tracing data exists openchoreo#3435 (root bug report)
• fix: return empty result when OpenObserve stream not yet created openchoreo#3439 (sibling PR in the main repo, being re-pointed at this)

Bug

When a component has never emitted spans, OpenObserve responds to a search with HTTP 400 and body {"code":20002,"message":"Search stream not found: default"} because the search stream is created lazily on first write. The adapter's executeSearchQuery currently treats any non-200 as a hard failure, so "no data yet" surfaces as HTTP 500 to the API client through the observer interface.

Approach

Single file edit on the adapter side, plus tests. All changes are confined to observability-tracing-openobserve/internal/openobserve/.

• New constant openObserveStreamNotFoundCode = 20002 and a small isStreamNotFound([]byte) bool helper that parses the OpenObserve error envelope. Tolerant: empty body, malformed JSON, or JSON without code all return false, so existing error paths are unchanged for everything except this one specific OpenObserve response.
• New exported sentinel ErrStreamNotFound (Go convention for "expected non-error state", like sql.ErrNoRows).
• executeSearchQuery returns the sentinel when the body indicates code 20002.
• Each public client method (GetTraces, GetSpans, GetSpanDetail) translates the sentinel into the appropriate zero-value result and nil error. For GetTraces/GetSpans, if only the count query returns the sentinel (rare), the search results are returned with Total = len(results) rather than failing.

Tests

Four new tests in client_test.go:

• TestExecuteSearchQuery_StreamNotFound - asserts the sentinel is returned for a 400+code:20002 response.
• TestGetTraces_StreamNotFound - asserts the public API returns an empty *TracesResult and nil error.
• TestGetSpans_StreamNotFound - symmetric for spans.
• TestIsStreamNotFound - table-driven test for the parser (matching code, other code, missing code, empty body, malformed JSON).

All pass; existing tests unaffected; go vet clean.

What this doesn't change

• The observer interface in openchoreo/openchoreo. The companion PR there (#3439) can now be closed in favor of this one - the OpenObserve-specific behavior lives where it should.
• The metrics or logs adapters. The same pattern likely applies if those streams are also lazy, but I kept this PR scoped to tracing for reviewability. Happy to follow up with symmetric PRs against observability-logs-openobserve and observability-metrics-* if you'd like.

This contribution was developed with AI assistance (Claude Code).

Summary by CodeRabbit

• Bug Fixes

  • Improved handling when a configured search stream is missing: trace and span list queries now return empty results (with preserved timing/total metadata) instead of failing, and span detail requests return a consistent "span not found" response.

• Tests

  • Added unit tests covering missing-stream scenarios, varied response bodies, and mixed count/list outcomes.

• Chores

  • Bumped chart version and appVersion for the observability tracing package.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 5cffeef3-e0a8-41b2-b083-04b7ba5c110c

📥 Commits

Reviewing files that changed from the base of the PR and between 8061aa1 and b9dba36.

📒 Files selected for processing (2)

• observability-tracing-openobserve/helm/Chart.yaml
• observability-tracing-openobserve/internal/openobserve/client_test.go

✅ Files skipped from review due to trivial changes (1)

• observability-tracing-openobserve/helm/Chart.yaml

🚧 Files skipped from review as they are similar to previous changes (1)

• observability-tracing-openobserve/internal/openobserve/client_test.go

---

📝 Walkthrough

Walkthrough

Adds ErrStreamNotFound sentinel and detection helper, makes executeSearchQuery return it when OpenObserve signals a missing stream, and updates GetTraces/GetSpans/GetSpanDetail to treat that case as "no data" (or "span not found"); tests and a Helm chart version bump included.

Changes

Stream-not-found error handling

Layer / File(s)	Summary
Stream-not-found error contract and detection primitives observability-tracing-openobserve/internal/openobserve/client.go	Adds errors import, defines ErrStreamNotFound sentinel, introduces internal error-code constant, and implements isStreamNotFound helper to parse the error envelope.
Query execution error detection observability-tracing-openobserve/internal/openobserve/client.go	executeSearchQuery inspects non-200 response bodies for the stream-not-found error code and returns ErrStreamNotFound instead of a generic status error.
GetTraces stream-not-found handling observability-tracing-openobserve/internal/openobserve/client.go	Main list query converts ErrStreamNotFound to an empty TracesResult; the separate count query also treats it as non-fatal, returning totals derived from parsed traces and setting TookMs from the successful response.
GetSpans stream-not-found handling observability-tracing-openobserve/internal/openobserve/client.go	Main list query converts ErrStreamNotFound to an empty SpansResult; the separate count query also treats it as non-fatal, returning totals derived from parsed spans and setting TookMs from the successful response.
GetSpanDetail stream-not-found handling observability-tracing-openobserve/internal/openobserve/client.go	Converts ErrStreamNotFound into a "span not found" error message keyed by traceId and spanId, consistent with zero-hit behavior.
Test coverage for stream-not-found behavior observability-tracing-openobserve/internal/openobserve/client_test.go	Adds errors import and tests verifying executeSearchQuery returns ErrStreamNotFound, that GetTraces/GetSpans return non-nil empty results (and CountQueryOnly scenarios), and that isStreamNotFound detects the condition across multiple JSON shapes.
Helm chart metadata observability-tracing-openobserve/helm/Chart.yaml	Bumps version and appVersion from 0.2.2 to 0.2.3.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Possibly related issues

• Traces API returns 500 when no tracing data exists openchoreo#3435 — Implements detection of OpenObserve code: 20002 and maps it to ErrStreamNotFound so list queries return empty results instead of failing.

Poem

I sniffed the stream and found it thin,
The query answered with a grin.
No traces there, the logs are mild —
I hop along, a satisfied child.
🐇✨

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 11.11% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately summarizes the main change: handling the OpenObserve stream-not-found case by returning empty results instead of errors when a stream hasn't been created yet.
Description check	✅ Passed	The description comprehensively covers Purpose, Approach, related issues, and testing strategy with clear context on the bug, solution, and scope boundaries.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

Warning

There were issues while running some tools. Please review the errors and either fix the tool's configuration or disable the tool if it's a critical failure.

🔧 golangci-lint (2.12.2)

level=error msg="[linters_context] typechecking error: pattern ./...: directory prefix . does not contain main module or its selected dependencies"

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[coderabbitai]

Actionable comments posted: 2

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@observability-tracing-openobserve/internal/openobserve/client_test.go`:
- Around line 971-1046: Add a unit test for GetSpanDetail that verifies
stream-not-found is translated into a "span not found" error: spin up an
httptest server that returns HTTP 400 with body {"code":20002,"message":"Search
stream not found: default"}, create the client with newTestClient(server.URL),
call client.GetSpanDetail(context.Background(),
TracesQueryParams{TraceID:"trace-1", SpanID:"span-1"}), assert that err is
non-nil and that err.Error() contains both "span" and "not found" (use
TestGetSpanDetail_StreamNotFound as the test name to match existing style).
- Around line 985-1003: Add tests that exercise the count-query-only
stream-not-found path: create TestGetTraces_StreamNotFound_CountQueryOnly (and a
symmetric TestGetSpans_StreamNotFound_CountQueryOnly) that spins up an
httptest.Server which returns a successful body for the main query endpoint
(containing one or more traces/spans) but returns HTTP 400 with JSON
{"code":20002,...} for the count endpoint; call client.GetTraces /
client.GetSpans (using newTestClient and TracesQueryParams/SpansQueryParams),
assert err == nil, result is non-nil, len(result.Traces or result.Spans) matches
the returned items and result.Total == len(result.Traces or result.Spans) to
verify the sentinel on the count query sets Total to the number of returned
items.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 5cc3f913-f93f-4be1-9021-2b8c11a65af5

📥 Commits

Reviewing files that changed from the base of the PR and between fe64eb8 and 6edec74.

📒 Files selected for processing (2)

• observability-tracing-openobserve/internal/openobserve/client.go
• observability-tracing-openobserve/internal/openobserve/client_test.go

[codecov-commenter]

Codecov Report

❌ Patch coverage is 50.00000% with 14 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...tracing-openobserve/internal/openobserve/client.go	50.00%	11 Missing and 3 partials ⚠️

📢 Thoughts on this report? Let us know!