Adjust logging and error handling in the client

* HTTP responses in the error range (400+) now properly turn into errors
* ROJO_EPIPHANY_DEV_CREATE now creates more verbose configuration
* Default configuration values are now much more explicit
* Errors that cause session termination are labeled more clearly.

plugin/src/ApiContext.lua

@@ -11,6 +11,14 @@ ApiContext.__index = ApiContext
 -- TODO: Audit cases of errors and create enum values for each of them.
 ApiContext.Error = {
 	ServerIdMismatch = "ServerIdMismatch",
+
+	-- The server gave an unexpected 400-category error, which may be the
+	-- client's fault.
+	ClientError = "ClientError",
+
+	-- The server gave an unexpected 500-category error, which may be the
+	-- server's fault.
+	ServerError = "ServerError",
 }
 
 setmetatable(ApiContext.Error, {
@@ -19,6 +27,18 @@ setmetatable(ApiContext.Error, {
 	end
 })
 
+local function rejectFailedRequests(response)
+	if response.code >= 400 then
+		if response.code < 500 then
+			return Promise.reject(ApiContext.Error.ClientError)
+		else
+			return Promise.reject(ApiContext.Error.ServerError)
+		end
+	end
+
+	return response
+end
+
 function ApiContext.new(baseUrl)
 	assert(type(baseUrl) == "string")
 
@@ -43,6 +63,7 @@ function ApiContext:connect()
 	local url = ("%s/api/rojo"):format(self.baseUrl)
 
 	return Http.get(url)
+		:andThen(rejectFailedRequests)
 		:andThen(function(response)
 			local body = response:json()
 
@@ -102,9 +123,7 @@ function ApiContext:read(ids)
 	local url = ("%s/api/read/%s"):format(self.baseUrl, table.concat(ids, ","))
 
 	return Http.get(url)
-		:catch(function(err)
-			return Promise.reject(err)
-		end)
+		:andThen(rejectFailedRequests)
 		:andThen(function(response)
 			local body = response:json()
 
@@ -129,6 +148,7 @@ function ApiContext:retrieveMessages()
 
 			return Promise.reject(err)
 		end)
+		:andThen(rejectFailedRequests)
 		:andThen(function(response)
 			local body = response:json()
 

plugin/src/Components/App.lua

@@ -95,8 +95,7 @@ function App:render()
 						address = address,
 						port = port,
 						onError = function(message)
-							Logging.warn("%s", tostring(message))
-							Logging.trace("Session terminated due to error")
+							Logging.warn("Rojo session terminated because of an error:\n%s", tostring(message))
 							self.currentSession = nil
 
 							self:setState({

plugin/src/DevSettings.lua

@@ -1,12 +1,22 @@
 local Config = require(script.Parent.Config)
 
+local VALUES = {
+	LogLevel = {
+		type = "IntValue",
+		defaultUserValue = 2,
+		defaultDevValue = 3,
+	},
+}
+
+local CONTAINER_NAME = "RojoDevSettings" .. Config.codename
+
 local function getValueContainer()
-	return game:FindFirstChild("RojoDev-" .. Config.codename)
+	return game:FindFirstChild(CONTAINER_NAME)
 end
 
 local valueContainer = getValueContainer()
 
-local function getValue(name)
+local function getStoredValue(name)
 	if valueContainer == nil then
 		return nil
 	end
@@ -20,7 +30,7 @@ local function getValue(name)
 	return valueObject.Value
 end
 
-local function setValue(name, kind, value)
+local function setStoredValue(name, kind, value)
 	local object = valueContainer:FindFirstChild(name)
 
 	if object == nil then
@@ -37,11 +47,13 @@ local function createAllValues()
 
 	if valueContainer == nil then
 		valueContainer = Instance.new("Folder")
-		valueContainer.Name = "RojoDev-" .. Config.codename
+		valueContainer.Name = CONTAINER_NAME
 		valueContainer.Parent = game
 	end
 
-	setValue("LogLevel", "IntValue", getValue("LogLevel") or 2)
+	for name, value in pairs(VALUES) do
+		setStoredValue(name, value.type, value.defaultDevValue)
+	end
 end
 
 _G[("ROJO_%s_DEV_CREATE"):format(Config.codename:upper())] = createAllValues
@@ -53,7 +65,7 @@ function DevSettings:isEnabled()
 end
 
 function DevSettings:getLogLevel()
-	return getValue("LogLevel")
+	return getStoredValue("LogLevel") or VALUES.LogLevel.defaultUserValue
 end
 
 return DevSettings

plugin/src/HttpResponse.lua

@@ -31,4 +31,4 @@ function HttpResponse:json()
 	return HttpService:JSONDecode(self.body)
 end
 
-return HttpResponse
+return HttpResponse

plugin/src/Logging.lua

@@ -1,7 +1,5 @@
 local DevSettings = require(script.Parent.DevSettings)
 
-local testLogLevel = nil
-
 local Level = {
 	Error = 0,
 	Warning = 1,
@@ -9,17 +7,14 @@ local Level = {
 	Trace = 3,
 }
 
+local testLogLevel = nil
+
 local function getLogLevel()
 	if testLogLevel ~= nil then
 		return testLogLevel
 	end
 
-	local devValue = DevSettings:getLogLevel()
-	if devValue ~= nil then
-		return devValue
-	end
-
-	return Level.Info
+	return DevSettings:getLogLevel()
 end
 
 local function addTags(tag, message)