Monitoring with Prometheus

Mydia can expose metrics for Prometheus at /metrics. It is off by default.

Turn it on

Set MYDIA_METRICS_ENABLED=true and restart Mydia.

The endpoint has no authentication. Anyone who can reach it can read your library size, download counts and which queues are busy. Scrape it over your LAN or container network, and do not route /metrics through a public reverse proxy. With Traefik, Caddy or nginx in front, block the path there.

If the player is enabled, Mydia also starts an HTTPS listener on HTTPS_PORT (default 4443) that serves the same router, so /metrics is reachable there too. Do not publish or forward that port while metrics are on, unless something in front of it blocks /metrics.

Scrape it

scrape_configs:
  - job_name: mydia
    scrape_interval: 30s
    static_configs:
      - targets: ["mydia:4000"]

What you get

Metric	What it tells you
`mydia_build_info{version}`	The running version
`mydia_uptime_seconds`	Time since the last restart
`mydia_vm_memory_bytes{kind}`	Memory use
`mydia_http_request_duration_milliseconds{route,method,status_class}`	Request latency and error rate by route
`mydia_liveview_mounts_total{view}`	Page loads in the web UI
`mydia_oban_jobs{queue,state}`	Background jobs waiting, running or retrying
`mydia_oban_job_duration_milliseconds{queue,worker}`	How long jobs take
`mydia_oban_job_failures_total{queue,worker}`	Jobs that failed
`mydia_library_items{type}`	Movies and shows
`mydia_library_episodes{state,monitored}`	Downloaded, missing, upcoming and unannounced episodes
`mydia_library_media_files`, `mydia_library_size_bytes`	Files and bytes on disk, excluding trash
`mydia_downloads{state}`	Active, failed and awaiting-import downloads
`mydia_download_client_up{client}`	1 when a download client's last health check passed
`mydia_hls_sessions{mode}`, `mydia_direct_play_sessions{kind}`	Active streams

Gauges refresh every 15 seconds (memory, streams) or every minute (library, downloads, jobs, client health).

Example alerts

- alert: MydiaDownloadClientDown
  expr: mydia_download_client_up == 0
  for: 10m
- alert: MydiaJobsRetrying
  expr: sum(mydia_oban_jobs{state="retryable"}) > 20
  for: 30m