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+# Observability: OTLP log export
+
+The sensing server can export every `tracing` log event as an
+OpenTelemetry log record over OTLP, with a curated set of sensing events
+(presence transitions, vitals estimates, node online/offline, fall
+detections, CSI capture stats, MQTT errors, model loads) carrying
+registry-backed event names and attributes under the `ruview.*`
+namespace.
+
+## The event registry
+
+The names are not ad hoc: they are defined in a weaver-validated
+semantic-conventions registry at `semconv/registry/` (attributes and log
+event names, OpenTelemetry registry format). The Rust constants module
+`v2/crates/wifi-densepose-sensing-server/src/semconv.rs` is **generated**
+from that registry (`weaver registry generate`, template under
+`templates/registry/rust/`) and CI (`.github/workflows/semconv.yml`)
+fails if either the registry stops validating or the generated module
+drifts. Executed Rust tests additionally reject any hard-coded
+`ruview.*` instrumentation key that is absent from the generated registry.
+Exported resources carry the registry's schema URL so downstream consumers
+can identify the exact conventions version.
+
+Curated events:
+
+| Event | Emitted when |
+| --- | --- |
+| `ruview.node.online` | first frame from a sensing node (CSI or edge vitals) |
+| `ruview.node.offline` | node evicted after 60 s without frames |
+| `ruview.presence.changed` | smoothed presence classification flips (transition-only) |
+| `ruview.vitals.estimate` | periodic breathing / heart-rate estimate (every 100 ticks) |
+| `ruview.fall.detected` | edge-vitals fall flag rising edge, per node |
+| `ruview.csi.stats` | periodic capture snapshot: frames processed, active nodes |
+| `ruview.mqtt.error` | MQTT publish/connection error in the HA publisher |
+| `ruview.model.loaded` | inference model loaded via the model API |
+
+## Enabling export
+
+Export is doubly gated so the default build and the default runtime are
+both unaffected:
+
+1. **Build** with the `otel` cargo feature (compiles in the OTLP
+   exporter stack, same gating principle as `mqtt`):
+
+   ```sh
+   cargo build --release -p wifi-densepose-sensing-server --features mqtt,otel
+   ```
+
+2. **Run** with `OTEL_EXPORTER_OTLP_ENDPOINT` set (unset ⇒ the OTLP
+   pipeline is never constructed and logging behaves exactly as before):
+
+   ```sh
+   OTEL_EXPORTER_OTLP_ENDPOINT=http://localhost:4317 \
+   ./target/release/sensing-server --source simulated
+   ```
+
+Use an `https://` collector endpoint outside a trusted local network. The
+`otel` feature includes Rustls and native certificate roots; standard OTLP
+environment variables can supply authentication headers. The Compose example
+uses plaintext only for container-to-container traffic on its private network.
+
+Logs export with resource attribute `service.name = "ruview"` and schema URL
+`https://raw.githubusercontent.com/ruvnet/RuView/main/semconv/schema/ruview-0.1.0.yaml`.
+Curated sensing
+events are emitted only after the configured exporter initializes
+successfully; without it, the pre-existing stderr output is unchanged.
+
+## Full stack: `docker compose`
+
+`docker/otel-compose.yml` brings up the whole pipeline —
+sensing server (synthetic CSI by default) → OpenTelemetry Collector →
+[Ourios](https://github.com/jensholdgaard/ourios), an OTLP-native log
+backend built on Parquet + online log-template mining + DataFusion:
+
+```sh
+docker compose -f docker/otel-compose.yml up
+```
+
+The collector and backend image tags are pinned to immutable multi-platform
+digests so the demo resolves to the reviewed images.
+
+Ourios derives the tenant from `service.name`, so all RuView logs land
+in tenant `ruview`.
+
+## Example queries
+
+Ourios mines every log line into a stable `template_id` online at
+ingest, which makes template-level questions cheap. Its query endpoint
+speaks a small logs DSL:
+
+Which log templates dominate RuView's output?
+
+```sh
+curl -s http://localhost:4319/v1/query \
+  -H 'X-Ourios-Tenant: ruview' \
+  -H 'Content-Type: text/plain' \
+  -d 'severity >= trace | range(-1h, now) | count by template_id | sort count desc | limit 10'
+```
+
+Recent warnings and errors (fall detections, MQTT failures):
+
+```sh
+curl -s http://localhost:4319/v1/query \
+  -H 'X-Ourios-Tenant: ruview' \
+  -H 'Content-Type: text/plain' \
+  -d 'severity >= warn | limit 50'
+```
+
+Did a RuView deploy change what the service logs? Template drift between
+two time windows (new / vanished / changed templates):
+
+```sh
+curl -s http://localhost:4319/v1/query \
+  -H 'X-Ourios-Tenant: ruview' \
+  -H 'Content-Type: text/plain' \
+  -d 'drift from -7d to now'
+```