deathtenk / clojure-watch

A Clojure library for watching file system events.

clojure-watch

The most user-friendly file-system watch library written in Clojure, built on top of the Java 7 WatchEvent API.

Installation

Add this to your dependencies:

[clojure-watch "LATEST"]

Check out Clojars for more specific installation instructions.

Usage

An example:

(ns clojure-watch.example
  (:require [clojure-watch.core :refer [start-watch]]))

(start-watch [{:path "/some/valid/path"
               :event-types [:create :modify :delete]
               :bootstrap (fn [path] (println "Starting to watch " path))
               :callback (fn [event filename] (println event filename))
               :options {:recursive true}}])

You call start-watch with a collection of specifications. A specification is a map with five entries:

1. :path. The path to a directory that you want to watch.
2. :event-types. A collection of the types of events that you want to watch. Possible values include :create, :modify, and :delete.
3. :bootstrap (optional). A function to be run only once when start-watch is invoked. The function should accept one argument: the path given in the spec.
4. :callback. A callback function to be invoked when an event occurs. The function should accept two arguments, the first one being the type of the event that happened (:create, :modify, or :delete), and the second one being the full path to the file to which the event happened.
5. :options. A map of options. Currently the only available option is :recursive. If it's set to true, all sub-directories will be watched.

Stop the watch

start-watch returns a function that can be called to stop the watch. For example:

(let [stop-watch (start-watch [{ :path "/some/valid/path" :event-types [:create :modify :delete] :callback (fn [event filename] (println event filename))}])] ; start the watch (Thread/sleep 20000) ; manipulate files on the path (stop-watch)) ; stop the watch

License

WTFPL.