🕵🏻‍ Extensible filesystem observation with callbacks

... for Android, BSDs, Linux, macOS, SunOS, Windows (MinGW, WSL)

mulle-monitor watches for the creation, deletion and updates of files in the working directory (and its sub-directories) using fswatch or inotifywait. It then matches those filenames against a set of patternfiles to determine the appropriate executable to call.

In mulle-sde mulle-monitor is mainly just used for starting tasks. The actual monitoring is rarely used.

Release Version	Release Notes
	RELEASENOTES

Commands

mulle-monitor callback

Callbacks are triggered for every matching event. A callback should not use much time. Preferably use it to select a task as tasks can be coalesced with other task events.

Add a callback for "hello":

cat <<EOF > my-callback.py
#!/usr/bin/env python
print "world"
EOF
mulle-monitor callback install hello my-callback.py

Remove a callback:

mulle-monitor callback remove hello

List all callbacks:

mulle-monitor callback list

mulle-monitor task

A task is a bash script plugin. It needs to define a function <task>_task_run to be a usable task plugin. Tasks are loaded into the mulle-monitor and they must be able to coexist with other tasks.

Tasks can be long running. It is ensure that only one task runs at a given time. Multiple callbacks in quick succession are coalesced into the run of a single task.

Add a source-able shell script for a task "world":

cat <<EOF > my-plugin.sh
world_task_run()
{
   echo "VfL Bochum 1848"
}
EOF
mulle-monitor task install world "my-plugin.sh"

Remove a task named "world":

mulle-monitor task remove world

List all tasks:

mulle-monitor task list

mulle-monitor run

mulle-monitor run

mulle-monitor run observes the working directory and waits for filesystem events.

If an incoming event can not be categorized as one of these three event types: create, update, delete it is ignored.

The filename that generated the event is then classified using patternfile matching (see mulle-monitor patternfile for more information). By this classification the type and category of the file are determined.

The callback will now be executed. As arguments it gets the event type (e.g. update), the filename, and the category of the matching patternfile.

The callback may produce a task name, by echoing it to stdout. If a task name is produced, then this task is loaded by mulle-monitor and executed.

The Wiki explains this also in much more detail.

mulle-monitor comes with no predefined patternfiles, callbacks, or tasks.

mulle-monitor find

This command is forward to mulle-match. See mulle_match for a more detailed description.

This example lists all the files, that pass through patternfiles of type "hello":

mulle-monitor find --match-filter "hello"

mulle-monitor match

This command is forward to mulle-match. See mulle_match for a more detailed description.

To test your installed patternfile you can use mulle-monitor match. It will output the callback name if a file matches.

mulle-monitor match pix/foo.svg

mulle-monitor patternfile

This command is forward to mulle-match. See mulle_match for a more detailed description.

Add a patternfile to select the callback "hello" for PNG files:

echo "*.svg" > pattern.txt
mulle-monitor patternfile install hello pattern.txt

You can optionally specify a category for the patternfile, which will be forwarded to the callback:

mulle-monitor patternfile install --category special hello pattern.txt

Remove a patternfile:

mulle-monitor patternfile remove hello

List all patternfiles:

mulle-monitor patternfile list

You are here

Install

See mulle-sde-developer how to install mulle-sde, which will also install mulle-monitor with required dependencies.

The command to install only the latest mulle-monitor into /usr/local (with sudo) is:

curl -L 'https://github.com/mulle-sde/mulle-monitor/archive/latest.tar.gz' \
 | tar xfz - && cd 'mulle-monitor-latest' && sudo ./bin/installer /usr/local

Author

Nat! for Mulle kybernetiK