Monitoring

Health Check

The simplest monitoring is the status endpoint:

curl http://localhost:8080/api/status

This is also used as the Docker healthcheck. A 200 OK response means the server is running and has GTFS data loaded.

Prometheus Metrics

Glove exposes metrics at GET /api/metrics in Prometheus text format. See the Metrics page for details.

Structured Logging

Glove uses the tracing crate for structured logging. Log level is configured in config.yaml:

server:
  log_level: "info"    # trace, debug, info, warn, error

Override at runtime with the RUST_LOG environment variable:

RUST_LOG=debug cargo run --release

Log Examples

INFO  glove::main > Starting Glove on 0.0.0.0:8080
INFO  glove::gtfs > Loaded 48000 stops, 320000 trips
INFO  glove::raptor > Built RAPTOR index in 12.3s
DEBUG glove::api::journeys > RAPTOR query: 2.3522;48.8566 → 2.2945;48.8584 in 342ms

Rate Limiting

Rate limiting is configured per IP address:

server:
  rate_limit: 20    # requests/sec, 0 = disabled

When the limit is exceeded, the server returns 429 Too Many Requests.

Graceful Shutdown

On SIGTERM or SIGINT, Glove:

1. Stops accepting new connections
2. Waits up to shutdown_timeout seconds for in-flight requests to complete
3. Exits cleanly

server:
  shutdown_timeout: 30    # seconds