Logs and ports

Logs

Kranz captures stdout and stderr for process services and actions. Detached services can provide lifecycle.logs.command, usually a following command such as docker compose logs -f. Its process is managed independently from the short-lived lifecycle start and stop commands.

The log panels support:

• regex filter and highlight modes;
• next and previous match navigation;
• wrapping and captured-at timestamps;
• pause/follow mode and unread counters;
• a pinned service above the currently focused log panel.

Declared ports

services:
  web:
    command: npm run dev
    ports: [3000]

Declared ports are checked before start. When a listener is already occupied, Kranz identifies whether it belongs to another managed service or an external process. An external process is only signalled after an explicit action and a fresh ownership check.

Runtime discovery

Without ports, discovery defaults on. Kranz scans listeners owned by the service process group, including child processes. With declared ports, discovery defaults off unless detect_ports: true is set.

services:
  web:
    command: npm run dev
    detect_ports: true
    ports: [3000]

Details distinguishes declared, detected, and declared · listening. Discovery uses lsof on macOS and ss on Linux.

Dynamic health targets

A TCP check without a static port can use a detected listener. An HTTP URL without an explicit port can do the same:

healthcheck:
  readiness:
    type: http
    url: http://127.0.0.1/ready
    detected_port_index: 0

When multiple listeners exist, set detected_port_index explicitly. The index addresses the sorted, deduplicated runtime port list.