adityamparikh opened a new pull request, #236:
URL: https://github.com/apache/solr-mcp/pull/236
## Summary
Logs one line per MCP tool call, so every tool call's trace has a log line
in Loki.
The services log only when something fails, so a successful `tools/call`
wrote nothing, and a trace's **Logs for this span** link in Grafana was empty
for every normal request. This adds an `ObservationHandler` for the
observations the `@Observed` tool services already create:
```
INFO ... o.a.s.m.s.o.ToolCallLoggingHandler : SearchService#search
completed in 47 ms
WARN ... o.a.s.m.s.o.ToolCallLoggingHandler : SearchService#search failed
after 9 ms: java.lang.IllegalArgumentException: Error from server at ...
```
- **Registration:** Spring Boot registers `ObservationHandler` beans with
the `ObservationRegistry`, so the handler is a package-private `@Component`,
like the reference docs' `ObservationPredicate` example. No configuration class
or customizer.
- **Scope:** it matches `ObservedAspect.ObservedAspectContext`, so only
`@Observed` method observations are logged. HTTP, security and other
observations are ignored, and the tool name comes from the join point, not from
tag strings.
- **Trace:** the line is written as the observation stops, under the
request's trace. Grafana's trace-to-logs query filters on the trace ID, so it
finds the line from any span in the trace.
- **STDIO:** `@Observed` observations exist only in the http profile, where
the annotations are enabled, so in STDIO the handler never runs.
- **Docs:** `docs/observability.md` and its site copy said successful tool
calls leave that link empty; updated to describe the new line.
**Depends on #230.** This branch is stacked on it because it edits the text
#230 adds; the first two commits in this PR are #230's and drop out once it
merges.
## Test plan
- [x] Ran the server in HTTP mode against `grafana/otel-lgtm`: a successful
`search` logs `completed in` at INFO, a `search` on a missing collection logs
`failed after` at WARN, `list-collections` logs its line, and `tools/list` logs
nothing.
- [x] Grafana's trace-to-logs query (`{service_name="solr-mcp"} | trace_id =
"<id>"`) for a successful `search` trace returns the `completed in` line;
before this change it returned nothing.
- [x] `./gradlew build` passes: 421 tests, 0 failures, 0 skipped (includes
the STDIO JSON-RPC test).
- No automated test for the log line itself; verified against LGTM as above.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
