Events (v0.11.0+)¶
The events mechanism allows lnav to be automated based on events that occur during processing. For example, filters could be added only when a particular log file format is detected instead of always installing them. Events are published through the lnav_events SQLite table. Reacting to events can be done by creating a SQLite trigger on the table and inspecting the content of the event.
Trigger Example¶
The following is an example of a trigger that adds an out filter when a
syslog file is loaded. You can copy the code into an .sql file and
install it by running lnav -i my_trigger.sql.
my_trigger.sql¶
1CREATE TRIGGER IF NOT EXISTS add_format_specific_filters
2 AFTER INSERT ON lnav_events WHEN
3 -- Check the event type
4 jget(NEW.content, '/$schema') =
5 'https://lnav.org/event-file-format-detected-v1.schema.json' AND
6 -- Only create the filter when a given format is seen
7 jget(NEW.content, '/format') = 'syslog_log' AND
8 -- Don't create the filter if it's already there
9 NOT EXISTS (
10 SELECT 1 FROM lnav_view_filters WHERE pattern = 'noisy message')
11BEGIN
12INSERT INTO lnav_view_filters (view_name, enabled, type, pattern) VALUES
13 ('log', 1, 'OUT', 'noisy message');
14END;
Reference¶
The following tables describe the schema of the event JSON objects.