Separate the network polling out, ready to move to a separate module.

src/lib/network-check.coffee

@@ -0,0 +1,36 @@
+Promise = require 'bluebird'
+request = Promise.promisifyAll require 'request'
+
+# options: The url to check, or an object of request options.
+#	timeout: 10s
+#	gzip: true
+exports.checkURL = checkURL = (options) ->
+	if typeof options is 'string'
+		options =
+			url: options
+	options.timeout ?= 10000
+	options.gzip ?= true
+	request
+	.getAsync(options)
+	.spread (response) ->
+		return response.statusCode in [ 200, 304 ]
+	.catch (e) ->
+		return false
+
+# options: The url to monitor, or an object of:
+#	interval: The time between each check.
+#	checkURL options
+# fn(bool connected): The function that will be called each time the state changes.
+exports.monitorURL = (options, fn) ->
+	interval = options?.interval or 0
+	connectivityState = null # Used to prevent multiple messages when disconnected
+	_check = ->
+		checkURL(options)
+		.then (connected) ->
+			return if connected == connectivityState
+			connectivityState = connected
+			fn(connected)
+			return # Do not wait on fn if it returns a promise
+		.finally ->
+			setTimeout(_check, interval)
+	_check()

src/utils.coffee

@@ -4,6 +4,7 @@ fs = Promise.promisifyAll require 'fs'
 config = require './config'
 mixpanel = require 'mixpanel'
 request = require './request'
+networkCheck = require './lib/network-check'
 
 utils = exports
 
@@ -64,18 +65,6 @@ exports.blink = (ms = 200) ->
 	.delay(ms)
 	.then -> fs.writeFileAsync(config.ledFile, 0)
 
-# Helps in checking connectivity by pseudo-pinging our endpoint.
-exports.checkConnectivity = ->
-	# We avoid using ICMP as this traffic is sometimes restricted/dropped. Good
-	# ol' port 80 HTTP should always be available :-)
-	request
-	.getAsync
-		url: config.heartbeatEndpoint
-		timeout: 10000
-	.spread (response) ->
-		return response.statusCode in [ 200, 304 ]
-	.catch ->
-		return false
 
 blinkPattern = do ->
 	started = false
@@ -105,19 +94,15 @@ blinkPattern = do ->
 			clearTimeout(timeout)
 	}
 
-exports.connectivityCheck = do ->
+
-	connectivityState = true # Used to prevent multiple messages when disconnected
+exports.connectivityCheck = _.once ->
-	_check = ->
+	networkCheck.monitorURL 
-		utils.checkConnectivity()
+		url: config.heartbeatEndpoint
-		.then (connected) ->
+		interval: 10 * 1000
-			return if connected == connectivityState
+		(connected) ->
-			connectivityState = connected
+			if connected
-			if connectivityState
 				console.log('Internet Connectivity: OK')
 				blinkPattern.stop()
 			else
 				console.log('Waiting for connectivity...')
-				blinkPattern.start()
+				blinkPattern.start()
-		.finally ->
-			setTimeout(_check, 10 * 1000) # Every 10 seconds perform this check.
-	return _.once(_check)