c577e2603ce98a6b5b832c4a7aa87bfc6ca27555
First sub-phase of ADR-0023 Phase 3 (telemetry sampler hot-reload), per the Mistral-produced phase plan validated 2026-05-05 (Q-037 in mistral-quirks.md). This is the isolated telemetry-package change: adds ReconfigureTracerProvider that builds a new TracerProvider with updated sampler settings, swaps the global, and gracefully shuts down the old. No-op when oldTP is nil (telemetry-disabled-at-startup is out of scope for Phase 3). The wiring (config callback → server-level invocation) lands in sub-phases 3.2 and 3.3 — kept separate for clean rollback semantics. Tests: - 3 new tests in pkg/telemetry/telemetry_test.go covering nil no-op, the global TP swap, and error-tolerance when old TP shutdown fails. - go test -race ./pkg/telemetry/... passes. Verifier verdict (skill-driven, mental run): APPROVE. Function is 17 lines, single responsibility, defensive on nil; tests cover positive + invariant + tolerance.
✨ feat(telemetry): ReconfigureTracerProvider for sampler hot-reload (ADR-0023 Phase 3, sub-phase 3.1)
dance-lessons-coach
Go web service demonstrating idiomatic package structure, versioned JSON API, and production-ready features.
Features
- Versioned JSON API (
/api/v1,/api/v2) - Chi router with graceful shutdown
- Zerolog structured logging (console and JSON modes)
- Viper configuration (file + env vars)
- Readiness endpoint for Kubernetes / service mesh
- OpenTelemetry / Jaeger distributed tracing
- OpenAPI / Swagger UI (embedded in binary)
- PostgreSQL user service with JWT auth
- BDD + unit tests
Quick Start
git clone https://gitea.arcodange.lab/arcodange/dance-lessons-coach.git
cd dance-lessons-coach
./scripts/build.sh # produces ./bin/server and ./bin/greet
./scripts/start-server.sh start
curl http://localhost:8080/api/health
curl http://localhost:8080/api/v1/greet/Alice
Stop: ./scripts/start-server.sh stop
Greet CLI
go run ./cmd/greet # Hello world!
go run ./cmd/greet Alice # Hello Alice!
Configuration
All options are available via config.yaml or DLC_* environment variables.
| Env var | Default | Description |
|---|---|---|
DLC_SERVER_PORT |
8080 |
Listening port |
DLC_SERVER_HOST |
0.0.0.0 |
Bind address |
DLC_LOGGING_JSON |
false |
JSON log format |
DLC_LOGGING_OUTPUT |
stderr | Log file path |
DLC_SHUTDOWN_TIMEOUT |
30s |
Graceful shutdown window |
DLC_API_V2_ENABLED |
false |
Enable /api/v2 routes |
DLC_CONFIG_FILE |
./config.yaml |
Override config path |
See config.example.yaml for a full template.
API
| Method | Path | Description |
|---|---|---|
| GET | /api/health |
Liveness check |
| GET | /api/ready |
Readiness check (503 during shutdown) |
| GET | /api/version |
Version info (?format=plain|full|json) |
| GET | /api/v1/greet/ |
Default greeting |
| GET | /api/v1/greet/{name} |
Named greeting |
| POST | /api/v2/greet |
V2 greeting with validation |
| GET | /swagger/ |
Swagger UI |
Testing
go test ./... # unit + integration tests
./scripts/test-graceful-shutdown.sh # lifecycle + JSON logging validation
./scripts/test-opentelemetry.sh # tracing end-to-end
Gitea Client
AI agent helper script at .vibe/skills/gitea-client/scripts/gitea-client.sh.
Auth setup:
echo "your_token" > ~/.gitea_token
chmod 600 ~/.gitea_token
export GITEA_API_TOKEN_FILE="$HOME/.gitea_token"
Get a token at https://gitea.arcodange.lab → Profile → Settings → Applications.
Architecture
Key decisions are documented in adr/. See AGENTS.md for the full development reference (commands, config, ADR index, commit conventions).
License
MIT
Description
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