log-prefix

Log prefix

The global prefix option controls the per-line tag prepended to every child's log output. Tokens are space-separated and applied in order.

Config

prefix: "timestamp service"
processes:
  - name: app
    command: /bin/sh
    args: ["-c", "echo hello-from-app; sleep 300"]
    on-failure: shutdown

• prefix — global format. Tokens:
  • timestamp — UTC timestamp (e.g. 2026-06-08T21:11:40.666Z).
  • service — [name] tag.
  • none — no prefix at all (raw output).
• The default when omitted is service timestamp. timestamp service swaps the order, producing 2026-06-08T21:11:40.666Z [app] line.
• A process may override the global prefix with its own per-process prefix.

Expected behavior

• app writes hello-from-app to stdout.
• gopherd prefixes the line with the configured tokens: 2026-06-08T21:11:40.666Z [app] hello-from-app.

Test

The test asserts status app is running, then queries logs app (non-follow), which returns the recent ring-buffer lines for the service. It asserts the captured line contains both hello-from-app and the [app] service prefix, then SIGTERM yields a clean exit 0.

go test ./documentation/log-prefix/ -v