Logs were a separate pipeline: env_logger in debug (never exported) and
opentelemetry-appender-log in release (exported without trace context,
so SigNoz could not link logs to traces).
- tracing-subscriber `tracing-log` feature: try_init installs LogTracer,
so log:: records become tracing events: one console format, and
RUST_LOG per-module directives still apply to them.
- opentelemetry-appender-tracing exports events as OTel log records when
OTLP_OTLS_ENDPOINT is set (any build), stamped with the enclosing
span's trace_id/span_id. A per-layer filter drops the exporter's own
crates.
- The OTel span layer keeps only WARN/ERROR events as span events; the
info/debug copies duplicated the correlated logs.
- Remove env_logger init in the server, init_logs, and the unused
opentelemetry-appender-log / opentelemetry-stdout deps.
- tests/otel_log_correlation.rs pins correlation (native + bridged),
the span-event filter, and per-module filtering of bridged records.
- Constitution 1.2.0 (Principle V logging rule), CLAUDE.md, README,
.env.example.
Closes#147
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
