Avoid stopping the VPN until a remote target state has been fetched, and retry applying config variables when they fail

Change-Type: patch
Signed-off-by: Pablo Carranza Velez <pablo@resin.io>

src/application.coffee

@@ -466,6 +466,7 @@ apiPollInterval = (val) ->
 	console.log('New API poll interval: ' + val)
 	clearInterval(updateStatus.intervalHandle)
 	application.poll()
+	return true
 
 setLocalMode = (val) ->
 	mode = checkTruthy(val) ? false
@@ -490,6 +491,7 @@ setLocalMode = (val) ->
 					unlockAndStart(app)
 		.then ->
 			application.localMode = mode
+	.return(true)
 
 specialActionConfigVars = [
 	[ 'RESIN_SUPERVISOR_LOCAL_MODE', setLocalMode ]
@@ -501,15 +503,19 @@ specialActionConfigVars = [
 
 executedSpecialActionConfigVars = {}
 
-executeSpecialActionsAndHostConfig = (conf, oldConf) ->
+executeSpecialActionsAndHostConfig = (conf, oldConf, opts) ->
+	updatedValues = _.clone(oldConf)
+	needsReboot = false
 	Promise.mapSeries specialActionConfigVars, ([ key, specialActionCallback ]) ->
 		if (conf[key]? or oldConf[key]?) and specialActionCallback?
 			# This makes the Special Action Envs only trigger their functions once.
 			if executedSpecialActionConfigVars[key] != conf[key]
 				logSpecialAction(key, conf[key])
 				Promise.try ->
-					specialActionCallback(conf[key])
-				.then ->
+					specialActionCallback(conf[key], logSystemMessage, opts)
+				.then (updated) ->
+					if updated
+						updatedValues[key] = conf[key]
 						executedSpecialActionConfigVars[key] = conf[key]
 					logSpecialAction(key, conf[key], true)
 	.then ->
@@ -519,14 +525,22 @@ executeSpecialActionsAndHostConfig = (conf, oldConf) ->
 			return _.startsWith(key, device.hostConfigConfigVarPrefix)
 		if !_.isEqual(hostConfigVars, oldHostConfigVars)
 			device.setHostConfig(hostConfigVars, oldHostConfigVars, logSystemMessage)
+			.then (changedHostConfig) ->
+				needsReboot = changedHostConfig
+				if changedHostConfig
+					_.forEach oldHostConfigVars, (val, key) ->
+						delete updatedValues[key]
+					_.assign(updatedValues, hostConfigVars)
+	.then ->
+		return { updatedValues, needsReboot }
 
-getAndApplyDeviceConfig = ->
+getAndApplyDeviceConfig = ({ initial = false } = {}) ->
 	deviceConfig.get()
 	.then ({ values, targetValues }) ->
-		executeSpecialActionsAndHostConfig(targetValues, values)
-		.tap ->
-			deviceConfig.set({ values: targetValues }) if !_.isEqual(values, targetValues)
-		.then (needsReboot) ->
+		executeSpecialActionsAndHostConfig(targetValues, values, { initial })
+		.tap ({ updatedValues }) ->
+			deviceConfig.set({ values: updatedValues }) if !_.isEqual(values, updatedValues)
+		.then ({ needsReboot }) ->
 			if needsReboot
 				logSystemMessage('Rebooting', {}, 'Reboot')
 				Promise.delay(1000)
@@ -922,7 +936,7 @@ application.initialize = ->
 	listenToEvents()
 	migrateContainerIdApps()
 	.then ->
-		getAndApplyDeviceConfig()
+		getAndApplyDeviceConfig(initial: true)
 	.then ->
 		knex('app').whereNot(markedForDeletion: true).orWhereNull('markedForDeletion').select()
 	.map (app) ->

src/utils.coffee

@@ -184,12 +184,14 @@ exports.enableConnectivityCheck = (val) ->
 	enabled = checkTruthy(val) ? true
 	disableCheck(!enabled)
 	console.log("Connectivity check enabled: #{enabled}")
+	return true
 
 # Callback function to enable/disable logs
 exports.resinLogControl = (val) ->
 	logEnabled = checkTruthy(val) ? true
 	logger.disableLogPublishing(!logEnabled)
 	console.log('Logs enabled: ' + val)
+	return true
 
 emptyHostRequest = request.defaults({ headers: Host: '' })
 gosuperRequest = (method, endpoint, options = {}, callback) ->
@@ -210,14 +212,20 @@ exports.gosuper = gosuper =
 	getAsync: Promise.promisify(gosuperGet, multiArgs: true)
 
 # Callback function to enable/disable VPN
-exports.vpnControl = (val) ->
+exports.vpnControl = (val, logMessage, { initial = false } = {}) ->
 	enable = checkTruthy(val) ? true
+	# If it's the initial run, we always want the VPN enabled, so we ignore calls to disable it
+	if initial and !enable
+		return Promise.resolve(false)
 	gosuper.postAsync('/v1/vpncontrol', { json: true, body: Enable: enable })
 	.spread (response, body) ->
 		if response.statusCode == 202
 			console.log('VPN enabled: ' + enable)
+			return true
 		else
-			console.log('Error: ' + body + ' response:' + response.statusCode)
+			logMessage("Error (#{response.statusCode}) toggling VPN: #{body}", {}, 'Toggle VPN error')
+			return false
+	.catchReturn(false)
 
 exports.AppNotFoundError = class AppNotFoundError extends TypedError