system_notifier

This plugin adds system notifications based on journal logs (or any program's output). It monitors specified sources for log entries matching predefined patterns and generates notifications accordingly (after applying an optional filter).

Sources are commands that return a stream of text (eg: journal, mqtt, tail -f, ...) which is sent to a parser that will use a regular expression pattern to detect lines of interest and optionally transform them before sending the notification.

Minimal configuration:

[[system_notifier.sources]]
command = "sudo journalctl -fx"
parser = "journal"

In general you will also need to define some parsers. By default a "journal" parser is provided, otherwise you need to define your own rules. This built-in configuration is close to this one, provided as an example:

[[system_notifier.parsers.journal]]
pattern = "([a-z0-9]+): Link UP$"
filter = "s/.*\[\d+\]: ([a-z0-9]+): Link.*/\1 is active/"
color= "#00aa00"

[[system_notifier.parsers.journal]]
pattern = "([a-z0-9]+): Link DOWN$"
filter = "s/.*\[\d+\]: ([a-z0-9]+): Link.*/\1 is inactive/"
color= "#ff8800"

[[system_notifier.parsers.journal]]
pattern = "Process \d+ \(.*\) of .* dumped core."
filter = "s/.*Process \d+ \((.*)\) of .* dumped core./\1 dumped core/"
color= "#aa0000"

[[system_notifier.parsers.journal]]
pattern = "usb \d+-[0-9.]+: Product: "
filter = "s/.*usb \d+-[0-9.]+: Product: (.*)/USB plugged: \1/"

Added in version 2.2.0

Configuration

sources

List of sources to enable (by default nothing is enabled)

Each source must contain a command to run and a parser to use.

You can also use a list of parsers, eg:

[[system_notifier.sources]]
command = "sudo journalctl -fkn"
parser = ["journal", "custom_parser"]

command

This is the long-running command (eg: tail -f <filename>) returning the stream of text that will be updated. Aa common option is the system journal output (eg: journalctl -u nginx)

parser

Sets the list of rules / parser to be used to extract lines of interest. Must match a list of rules defined as system_notifier.parsers.<parser_name>.

parsers

A list of available parsers that can be used to detect lines of interest in the sources and re-format it before issuing a notification.

Each parser definition must contain a pattern and optionally a filter and a color.

pattern

[[system_notifier.parsers.custom_parser]]

pattern = 'special value:'

The pattern is any regular expression.

filter

The filters allows to change the text before the notification, eg: filter="s/.*special value: (\d+)/Value=\1/" will set a filter so a string "special value: 42" will lead to the notification "Value=42"

color

You can also provide an optional color in "hex" or "rgb()" format

color = "#FF5500"

default_color (optional)

Sets the notification color that will be used when none is provided in a parser definition.

[system_notifier]
default_color = "#bbccbb"