Module observability 

Pipeline-internal observability: tracing spans and metrics counters/ histograms wired automatically around every source, sink, transform, and state-store operation. See docs/superpowers/specs/2026-05-23-observability-otel-prometheus-design.md.

Structs

DurationGuard

On Drop, records the elapsed time since construction into the named histogram with the supplied labels. Recording on drop guarantees a sample even if the surrounding future is cancelled or panics.

InstallReport

Report from install_observability so callers can log what actually happened (recorder installed vs. already-installed vs. disabled).

InstrumentedSink

Wraps a &dyn Sink (or any &S: Sink) and emits spans + metrics around write_batch and flush. Constructed by Pipeline::run.

InstrumentedSource

Wraps a &dyn Source (or any &S: Source) and emits spans + metrics around every call. Constructed by Pipeline::run and never exposed to end users; the wrapped source remains the user-facing object.

InstrumentedStateStore

Wraps an Arc<dyn StateStore> and emits faucet.state.* spans + metrics around every operation.

Labels

Common labels carried by every span and metric.

ObservabilityConfig

Configuration for install_observability. Either or both sections may be None; unset sections install nothing.

PrometheusConfig

RunStreamOptions

TracingConfig

Enums

InstallError

Functions

install_observability

Install observability if requested. Always returns; never panics.

instrumented_apply_qualityquality

Apply the quality pass and emit metrics. Returns the same outcome as apply_quality; on abort, increments faucet_quality_aborts_total before propagating the error.

instrumented_apply_stages

Apply a sequence of compiled stages to every record in records, flat-mapping per stage. Emits one faucet.transform.apply span and counters faucet_transform_records_in_total / _records_out_total per call (per page).

register_build_info

Register the faucet_build_info{version} gauge (set to 1) under the currently-installed metrics recorder. Safe to call from any code path that wants to ensure the gauge is set; install_observability invokes this automatically. Gauges are naturally idempotent under the metrics model — repeat calls just re-set the same value.

strip_type_name

Strip a Rust type_name string to its final path segment.

update_bookmark_lag

Update the bookmark-lag gauges if the bookmark is a parseable RFC3339 timestamp. Returns true if the gauges were updated, false otherwise.