This is a module for accessing the all mighty Systemd Journal and its handy dandy key-value store hidden behind every log line. In the background it spawns a journalctl process with the output format json
and parses the serialised object stream.
Require the module and create a new instance:
const Journalctl = require('journalctl');
const journalctl = new Journalctl([opts]);
The optional object opts
can have the following properties:
identifier
: Just output logs of the given syslog identifier (cf. man journalctl, option '-t')unit
: Just output logs originated from the given unit file (cf. man journalctl, option '-u')filter
: An array of matches to filter by (cf. man journalctl, matches)all
: Show all fields in full, even if they include unprintable characters or are very long. (cf. man journalctl, option '-a')lines
: Show the most recent journal events and limit the number of events shown (cf. man journalctl, option '-n')since
: Start showing entries on or newer than the specified date (cf. man journalctl, option '-S')
journalctl.on('event', (event) => {});
Is fired on every log event and hands over the object event
describing the event. (Oh boy ... so many events in one sentence ...)
journalctl.stop([callback]);
Stops journalctl and calls the optional callback
once everything has been killed.