Ref #430 - Identify anonymous users by their hash and salted MAC address

See #430 for the underlying details.

package.json

@@ -72,7 +72,8 @@
 		"lodash": "~1.0.0",
 		"backbone": "0.9.9",
 		"watchr": "~2.3.7",
-		"yamljs": "~0.1.4"
+		"yamljs": "~0.1.4",
+		"getmac": "~1.0.4"
 	},
 	"optionalDependencies": {
 		"airbrake": "~0.2.9",

src/lib/docpad.coffee

@@ -764,6 +764,10 @@ class DocPad extends EventEmitterEnhanced
 		# By default it is only enabled if we are not running inside a test
 		reportStatistics: process.argv.join('').indexOf('test') is -1
 
+		# Hash Key
+		# The key that we use to hash some data before sending it to our statistic server
+		hashKey: '7>9}$3hP86o,4=@T'  # const
+
 		# Airbrake Token
 		airbrakeToken: 'e7374dd1c5a346efe3895b9b0c1c0325'
 
@@ -904,6 +908,7 @@ class DocPad extends EventEmitterEnhanced
 				docpad.log('warn', locale.trackError+'\n'+locale.errorFollows, err)
 		@trackRunnerInstance.total = Infinity
 
+
 		# Initialize a default logger
 		logger = new caterpillar.Logger(
 			transports:
@@ -983,6 +988,7 @@ class DocPad extends EventEmitterEnhanced
 		[instanceConfig,next] = balUtil.extractOptsAndCallback(instanceConfig,next)
 		docpad = @
 		locale = @getLocale()
+		mixpanelInstance = @getMixpanelInstance()
 
 		# Render Single Extensions
 		@DocumentModel::defaults.renderSingleExtensions = docpad.config.renderSingleExtensions
@@ -1005,41 +1011,68 @@ class DocPad extends EventEmitterEnhanced
 		tasks = new balUtil.Group (err) ->
 			# Error?
 			return docpad.error(err)  if err
+
 			# All done, forward our DocPad instance onto our creator
 			return next?(null,docpad)
 
 		# Welcome
 		tasks.push (complete) =>
+			# No welcome
 			return complete()  unless docpad.config.welcome
+
+			# Welcome
 			@emitSync('welcome', {docpad}, complete)
 
+		# Anyomous
+		tasks.push (complete) =>
+			# No statistics or username is already identified
+			return complete()  if !mixpanelInstance or @userConfig.username
+
+			# User is anonymous, set their username to the hashed and salted mac address
+			require('getmac').getMac (err,macAddress) =>
+				return complete()  if err
+
+				# Hash with salt
+				try
+					macAddressHash = require('crypto').createHmac('sha1',docpad.config.hashKey).update(macAddress).digest('hex')
+				catch err
+					return complete()  if err
+
+				# Apply
+				@userConfig.name ?= "MAC #{macAddressHash}"
+				@userConfig.username ?= macAddressHash
+				return complete()
+
 		# Track
 		tasks.push =>
-			if @userConfig.username
-				lastLogin = new Date()
-				countryCode = @getCountryCode()
-				languageCode = @getLanguageCode()
-				mixpanelInstance = @getMixpanelInstance()
-				if mixpanelInstance
-					if @userConfig.identified isnt true
-						# identify the new user with mixpanel
-						mixpanelInstance.people.set(@userConfig.username, {
-							$email: @userConfig.email
-							$name: @userConfig.name
-							$username: @userConfig.username
-							$created: lastLogin
-							$last_login: lastLogin
-							$country_code: countryCode
-							languageCode: languageCode
-						})
-						@updateUserConfig({
-							identified: true
-						})
-					else
-						# only update last login if we are another day
-						mixpanelInstance.people.set(@userConfig.username, {
-							$last_login: new Date()
-						})
+			# No stats or no username
+			return  if !mixpanelInstance or !@userConfig.username
+
+			# Update the user in mixpanel
+			lastLogin = new Date()
+			if @userConfig.identified isnt true
+				# Identify the new user with mixpanel
+				mixpanelInstance.people.set(@userConfig.username, {
+					$created: lastLogin
+					$username: @userConfig.username
+					$email: @userConfig.email
+					$name: @userConfig.name
+					$last_login: lastLogin
+					$country_code: @getCountryCode()
+					languageCode: @getLanguageCode()
+				})
+				@updateUserConfig({
+					identified: true
+				})
+			else
+				# Update existing user if they have already been identified
+				mixpanelInstance.people.set(@userConfig.username, {
+					$email: @userConfig.email
+					$name: @userConfig.name
+					$last_login: lastLogin
+					$country_code: @getCountryCode()
+					languageCode: @getLanguageCode()
+				})
 
 
 		# DocPad Ready