Logging in Hive Router

Logs are the first thing you reach for when something is wrong in production, and the last thing you want eating your throughput when everything is fine. We rewrote logging in Hive Router around that tension.

One Summary Line per Request

At the default info level, the router no longer prints its internal pipeline. Instead, every finished request produces a single structured summary, the router's access log:

{
  "timestamp": "2026-07-15T21:23:27.123456Z",
  "level": "info",
  "target": "router::request",
  "request_id": "01J8...",
  "trace_id": "4bf92f3577b34da6a3ce929d0e0e4736",
  "operation_name": "GetProduct",
  "operation_type": "query",
  "operation_hash": "1a9246e236afb66a7cccaf18c07c38f2",
  "subgraph_requests": 2,
  "involved_subgraphs": "products,reviews",
  "error_count": 0,
  "partial_response": false,
  "status_code": 200,
  "payload_bytes": 842,
  "duration_ms": 14
}

One line, flat fields, no nesting, predictable volume under load. Subscriptions and streamed responses are covered too: payload_bytes accumulates everything sent and duration_ms measures until the stream terminates.

Correlation with Traces

Every log line now carries a request_id (read from x-request-id, or generated) and, when a W3C traceparent is present, the trace_id. Since that is the same trace ID exported to your OpenTelemetry backend, you can find a slow request in your access log and jump straight to its distributed trace.

log:
  correlation:
    id_header: "x-request-id"
    trace_propagation: true

Targeted Filtering

Each log line is tagged with an explicit router:: target, so you can raise verbosity for one subsystem, or mute a chatty one, without touching the global level:

log:
  level: "info"
  filter: "router::executor=debug,router::request=off"

Logs from the crates the router depends on are suppressed by default; enable them with log_internals: true when you need to debug the runtime itself.

Simpler Formats

format is now json (default, for production) or text (human-readable, for local development). The previous pretty-tree and pretty-compact values are gone, replace them with text.

• Logging guide
• log configuration reference