Emit telemetry

pipeline.Main installs OpenTelemetry and Temporal instrumentation. User code adds domain information through pkg/obs; it does not configure exporters.

Logs

obs.Info(ctx, "package installed", obs.Str("name", pkg), obs.Int("attempt", n))
obs.Warn(ctx, "retrying", obs.Err(err))

Available levels are Debug, Info, Warn, and Error. Attributes use Str, Int, and Err. The worker automatically adds run, pipeline, activity, and entity correlation.

obs.RunTail(ctx, cmd, bytes) streams stdout/stderr while retaining a bounded tail for the returned error. Prefer it around external commands so the failure reason reaches the record's logs.

Metrics and spans

obs.Count(ctx, "packages.installed", 1, obs.Str("manager", "dnf"))
obs.Gauge(ctx, "queue.depth", depth)
obs.Measure(ctx, "download.seconds", elapsed)

ctx, span := obs.Span(ctx, "download", obs.Str("source", source))
defer span.End()

Count is an integer counter increment, Gauge records a value, and Measure records a floating-point measurement. Names should describe stable product signals rather than Go functions.

Durable events

err := obs.EventFor(ctx, "docker/db", "schema-migrated", payload)

An event is a durable domain milestone in the record's workflow history, not a log line. Use it sparingly: each event consumes history. In a resource activity, obs.Event uses the entity already attached to the context; use EventFor when acting on another record explicitly.

Read all dimensions through graphenectl observe or Studio. Backend wiring belongs to server configuration.