OpenTelemetry

pkg/otel manages the OpenTelemetry SDK lifecycle — initializing trace, metric, and log providers on startup and flushing them on shutdown.

Setup

lakta.NewRuntime(
    config.NewModule(
        config.WithConfigDirs(".", "./config"),
        config.WithArgs(os.Args[1:]),
    ),
    tint.NewModule(),
    slog.NewModule(),
    otel.NewModule(),   // after logger, before app modules
)

What gets registered

DI type	Description
trace.TracerProvider	OTLP trace exporter
metric.MeterProvider	OTLP metric exporter
*slog.Logger	OTel log bridge (wraps the existing logger)

Using traces

tracer := do.MustInvoke[trace.TracerProvider](injector).Tracer("my-service")

ctx, span := tracer.Start(ctx, "operation-name")
defer span.End()

Exporters per signal

exporters selects otlp or none per signal and replaces signals. Traces and metrics always get an SDK provider (spans record and trace IDs reach logs without a collector); logs get a provider only for otlp. Metrics are always readable through the private *prometheus.Registry the module provides in DI, which the management server exposes on /metrics.

modules:
  otel:
    otel:
      default:
        exporters: { traces: otlp, metrics: none, logs: none }

Configuration Reference

Config path: modules.otel.otel.<name>

service_namestringdefault: lakta

serviceName specifies the OpenTelemetry service name

envLAKTA_MODULES__OTEL__OTEL__<NAME>__SERVICE_NAME

service_versionstring

serviceVersion is included as semconv.ServiceVersionKey in the resource

envLAKTA_MODULES__OTEL__OTEL__<NAME>__SERVICE_VERSION

service_namespacestring

serviceNamespace is included as semconv.ServiceNamespaceKey in the resource

envLAKTA_MODULES__OTEL__OTEL__<NAME>__SERVICE_NAMESPACE

environmentstring

environment is the deployment environment (e.g. "production", "staging")

envLAKTA_MODULES__OTEL__OTEL__<NAME>__ENVIRONMENT

endpointstring

endpoint overrides the OTLP exporter endpoint. Empty uses the SDK default (env vars)

envLAKTA_MODULES__OTEL__OTEL__<NAME>__ENDPOINT

protocolstringdefault: grpc

protocol sets the OTLP transport: "grpc" (default), "http/protobuf", or "http/json"

envLAKTA_MODULES__OTEL__OTEL__<NAME>__PROTOCOL

insecurebool

insecure disables TLS on the OTLP connection — useful for local collectors

envLAKTA_MODULES__OTEL__OTEL__<NAME>__INSECURE

headersmap[string]string

headers are additional headers sent with every OTLP export (e.g. auth tokens)

envLAKTA_MODULES__OTEL__OTEL__<NAME>__HEADERS

sample_ratefloat64default: 1

sampleRate sets the trace sampling ratio. 1.0 = always sample, 0.0 = never sample

envLAKTA_MODULES__OTEL__OTEL__<NAME>__SAMPLE_RATE

metric_intervaltime.Durationdefault: 1m0s

metricInterval sets the periodic metric export interval

envLAKTA_MODULES__OTEL__OTEL__<NAME>__METRIC_INTERVAL

runtime_intervaltime.Durationdefault: 1s

runtimeInterval sets the minimum Go runtime stats collection interval

envLAKTA_MODULES__OTEL__OTEL__<NAME>__RUNTIME_INTERVAL

enabledbooldefault: true

enabled controls whether OTEL is set up. When false, noop providers are registered

envLAKTA_MODULES__OTEL__OTEL__<NAME>__ENABLED

requiredbool

required makes telemetry setup failures fatal. When false (default), setup

envLAKTA_MODULES__OTEL__OTEL__<NAME>__REQUIRED

signals[]stringdefault: ["traces","metrics","logs"]

signals lists which telemetry signals to enable: "traces", "metrics", "logs"

envLAKTA_MODULES__OTEL__OTEL__<NAME>__SIGNALS

exportersmap[string]string

exporters selects the exporter per signal ("traces", "metrics", "logs"):

envLAKTA_MODULES__OTEL__OTEL__<NAME>__EXPORTERS