FileSystem
A file change watcher wrapper based on fs
System Support
- Mac fsevent
- Linux and FreeBSD inotify
- Windows inotify-win
NOTE: On Linux and FreeBSD you need to install inotify-tools.
Usage
Put file_system
in the deps
and application
part of your mix.exs
defmodule Excellent.Mixfile do
use Mix.Project
def project do
...
end
defp deps do
[
{ :file_system, "~> 0.1.0", only: :test },
]
end
...
end
Subscription API
You can spawn a worker and subscribe to events from it:
{:ok, pid} = FileSystem.start_link(dirs: ["/path/to/some/files"])
FileSystem.subscribe(pid)
The pid you subscribed from will now receive messages like
{:file_event, worker_pid, {file_path, events}}
and
{:file_event, worker_pid, :stop}
Callback API
You can also use FileSystem
to define a module with a callback that will be called when filesystem events occur. This requires you to specify directories to watch at compile-time.
write lib/monitor.ex
defmodule Monitor do
use FileSystem, dirs: ["/tmp/test"]
def callback(:stop) do
IO.puts "STOP"
end
def callback(file_path, events) do
IO.inspect {file_path, events}
end
end
Execute in iex
iex > Monitor.start
Tweaking behaviour via listener extra arguments
For each platform, you can pass extra arguments to the underlying listener process via the listener_extra_args
option.
Here is an example to get instant notifications on file changes for Mac OS X:
use FileSystem, dirs: ["/tmp/test"], listener_extra_args: "--latency=0.0"
See the fs source for more details.
List Events from Backend
iex > FileSystem.known_events