Events Presenter Telemetry

This document describes the OpenTelemetry metrics and assets for Events Presenter.

For general setup instructions, see the OpenTelemetry Configuration guide.

Telemetry Assets

• dashboards/events-presenter-overview.dashboard.json: Grafana dashboard with panels for DB connectivity, request rate, latency, and real-time SSE event delivery statistics.
• collector/otel-collector-config.yaml: Minimal OpenTelemetry Collector configuration.

Metrics Reference

Naming note

In Prometheus, metric names are normalized with underscores (e.g., events_presenter_startup_success), and counters typically include the _total suffix.

Metrics Table

Metric	Type	Unit	Description	PromQL example
events_presenter.startup.success	Counter	count	Service startup completed successfully.	sum(increase(events_presenter_startup_success_total[1h]))
events_presenter.startup.failure	Counter	count	Service startup failed.	sum(increase(events_presenter_startup_failure_total[1h]))
events_presenter.db.connect.duration_seconds	Histogram	seconds	Time spent waiting for PostgreSQL readiness.	histogram_quantile(0.95, sum by (le) (rate(events_presenter_db_connect_duration_seconds_bucket[5m])))
events_presenter.http.events.requests	Counter	requests	Number of /events requests. Labels: method, status_code.	sum by (method) (rate(events_presenter_http_events_requests_total[5m]))
events_presenter.http.events.duration_seconds	Histogram	seconds	/events request latency. Labels: method, status_code.	histogram_quantile(0.95, sum by (le, method) (rate(events_presenter_http_events_duration_seconds_bucket[5m])))
events_presenter.http.events.resources_returned	Counter	resources	Number of resources returned by /events. Label: method.	sum(rate(events_presenter_http_events_resources_returned_total[5m]))
events_presenter.http.events.errors	Counter	errors	Errors in /events flow. Labels: method, stage, status_code.	sum by (stage) (rate(events_presenter_http_events_errors_total[5m]))
events_presenter.listener.notifications.received	Counter	notifications	PostgreSQL notifications received from LISTEN/NOTIFY.	sum(rate(events_presenter_listener_notifications_received_total[5m]))
events_presenter.listener.jobs.enqueued	Counter	jobs	Jobs enqueued after notifications.	sum(rate(events_presenter_listener_jobs_enqueued_total[5m]))
events_presenter.listener.load_latest.duration_seconds	Histogram	seconds	Duration of latest-events DB fetch after notification.	histogram_quantile(0.95, sum by (le) (rate(events_presenter_listener_load_latest_duration_seconds_bucket[5m])))
events_presenter.listener.load_latest.failure	Counter	failures	Failures in latest-events DB fetch path.	sum(increase(events_presenter_listener_load_latest_failure_total[1h]))
events_presenter.listener.connect.failure	Counter	failures	Failures while connecting/reconnecting listener to PostgreSQL.	sum(increase(events_presenter_listener_connect_failure_total[1h]))
events_presenter.listener.disconnects	Counter	disconnects	Listener disconnect events.	sum(increase(events_presenter_listener_disconnects_total[1h]))
events_presenter.sse.clients.connected	Counter	clients	Total SSE client subscriptions opened.	sum(increase(events_presenter_sse_clients_connected_total[1h]))
events_presenter.sse.clients.disconnected	Counter	clients	Total SSE client subscriptions closed.	sum(increase(events_presenter_sse_clients_disconnected_total[1h]))
events_presenter.sse.clients.active	Gauge	clients	Current number of active SSE subscribers.	max(events_presenter_sse_clients_active)
events_presenter.sse.events.broadcast	Counter	events	Events delivered to SSE client channels.	sum(rate(events_presenter_sse_events_broadcast_total[5m]))
events_presenter.sse.events.dropped	Counter	events	Events dropped due to slow SSE clients.	sum(rate(events_presenter_sse_events_dropped_total[5m]))