Change split function so it also returns empty fields; add API access control; support returning http status codes; changes towards support for running as uhttp embedded lua module.

src/config.lua

@@ -5,7 +5,7 @@ local M = {}
 M.DEBUG_PCALLS = true
 
 --REST responses will contain 'module' and 'function' keys describing what was requested
-M.API_INCLUDE_ENDPOINT_INFO = true
+M.API_INCLUDE_ENDPOINT_INFO = false
 
 M.DEFAULT_AP_SSID = "d3d-ap-%MAC_ADDR_TAIL%"
 M.DEFAULT_AP_ADDRESS = "192.168.10.1"

src/main.lua

@@ -1,3 +1,5 @@
+package.path = package.path .. ';/usr/share/lua/wifibox/?.lua'
+
 local l = require("logger")
 local RequestClass = require("rest.request")
 local ResponseClass = require("rest.response")
@@ -38,7 +40,8 @@ end
  local function main()
 	local rq = RequestClass.new(postData, config.DEBUG_PCALLS)
 	
-	l:info("received request of type " .. rq:getRequestMethod() .. " with arguments: " .. l:dump(rq:getAll()))
+	l:info("received request of type " .. rq:getRequestMethod() .. " for " .. (rq:getRequestedApiModule() or "<unknown>")
+			.. "/" .. (rq:getRealApiFunctionName() or "<unknown>") .. " with arguments: " .. l:dump(rq:getAll()))
 	if rq:getRequestMethod() ~= "CMDLINE" then
 		l:info("remote IP/port: " .. rq:getRemoteHost() .. "/" .. rq:getRemotePort())
 		l:debug("user agent: " .. rq:getUserAgent())
@@ -52,7 +55,6 @@ end
 		end
 		
 	else
-		io.write ("Content-type: text/plain\r\n\r\n")
 		local response, err = rq:handle()
 		
 		if err ~= nil then l:error(err) end

src/rest/api/api_test.lua

@@ -5,6 +5,15 @@ local M = {}
 
 M.isApi = true
 
+--empty or nil is equivalent to 'ANY', otherwise restrict to specified letters (command-line is always allowed)
+M._access = {
+	_global = "GET",
+	success = "GET", fail = "GET", error = "GET",
+	read = "GET", write = "POST", readwrite = "ANY", readwrite2 = "",
+	echo = "GET"
+}
+
+
 function M._global(request, response)
 	local ba = request:getBlankArgument()
 	
@@ -27,6 +36,13 @@ function M.error(request, response)
 	response:addData("url", "http://xkcd.com/1024/")
 end
 
+
+function M.read(request, response) response:setSuccess("this endpoint can only be accessed through GET request") end
+function M.write(request, response) response:setSuccess("this endpoint can only be accessed through POST request") end
+function M.readwrite(request, response) response:setSuccess("this endpoint can only be accessed through POST request") end
+function M.readwrite2(request, response) response:setSuccess("this endpoint can only be accessed through POST request") end
+
+
 function M.echo(request, response)
 	response:setSuccess("request echo")
 	response:addData("request_data", request:getAll())

src/rest/request.lua

@@ -17,6 +17,7 @@ M.requestedApiFunction = nil
 M.resolvedApiFunction = nil --will contain function address, or nil
 M.realApiFunctionName = nil --will contain requested name, or global name, or nil
 M.resolutionError = nil --non-nil means function could not be resolved
+M.moduleAccessTable = nil
 
 
 local function kvTableFromUrlEncodedString(encodedText)
@@ -31,6 +32,8 @@ end
 local function kvTableFromArray(argArray)
 	local args = {}
 	
+	if not argArray then return args end
+	
 	for _, v in ipairs(argArray) do
 		local split = v:find("=")
 		if split ~= nil then
@@ -45,8 +48,12 @@ end
 
 --NOTE: this function ignores empty tokens (e.g. '/a//b/' yields { [1] = a, [2] = b })
 local function arrayFromPath(pathText)
-	return pathText and pathText:split("/") or {} --FIXME: nothing returned? regardless of which sep is used
-	--return pathText:split("/")
+	return pathText and pathText:split("/") or {}
+end
+
+--returns true if acceptable is nil or empty or 'ANY' or if it contains requested
+local function matchRequestMethod(acceptable, requested)
+	return acceptable == nil or acceptable == '' or acceptable == 'ANY' or string.find(acceptable, requested)
 end
 
 
@@ -69,8 +76,11 @@ local function resolveApiModule(modname)
 	return modObj
 end
 
---returns funcobj+nil (usual), funcobj+number (global func with blank arg), or nil+errmsg (unresolvable or inaccessible)
+--returns resultData+nil (usual), or nil+errmsg (unresolvable or inaccessible)
+--resultData contains 'func', 'accessTable' and if found, also 'blankArg'
 local function resolveApiFunction(modname, funcname)
+	local resultData = {}
+	
 	if funcname and string.find(funcname, "_") == 1 then return nil, "function names starting with '_' are preserved for internal use" end
 	
 	local mod, msg = resolveApiModule(modname)
@@ -84,12 +94,17 @@ local function resolveApiFunction(modname, funcname)
 	local funcNumber = tonumber(funcname)
 	
 	if (type(f) == "function") then
-		return f
+		resultData.func = f
+		resultData.accessTable = mod._access
 	elseif funcNumber ~= nil then
-		return mod[GLOBAL_API_FUNCTION_NAME], funcNumber
+		resultData.func = mod[GLOBAL_API_FUNCTION_NAME]
+		resultData.accessTable = mod._access
+		resultData.blankArg = funcNumber
 	else
 		return nil, ("function '" .. funcname .. "' does not exist in API module '" .. modname .. "'")
 	end
+	
+	return resultData
 end
 
 
@@ -123,27 +138,24 @@ function M.new(postData, debug)
 	if debug and self.requestMethod == "CMDLINE" then
 		self.pathArgs = arrayFromPath(self.cmdLineArgs["p"])
 	end
+	table.remove(self.pathArgs, 1) --drop the first 'empty' field caused by the opening slash of the query string
 	
 	
 	if #self.pathArgs >= 1 then self.requestedApiModule = self.pathArgs[1] end
 	if #self.pathArgs >= 2 then self.requestedApiFunction = self.pathArgs[2] end
 	
---	if debug then
---		self.requestedApiModule = self.cmdLineArgs["m"] or self.requestedApiModule
---		self.requestedApiFunction = self.cmdLineArgs["f"] or self.requestedApiFunction
---	end
-	
 	if self.requestedApiModule == "" then self.requestedApiModule = nil end
 	if self.requestedApiFunction == "" then self.requestedApiFunction = nil end
 	
 	
 	-- Perform module/function resolution
-	local sfunc, sres = resolveApiFunction(self:getRequestedApiModule(), self:getRequestedApiFunction())
+	local rData, errMsg = resolveApiFunction(self:getRequestedApiModule(), self:getRequestedApiFunction())
 	
-	if sfunc ~= nil then --function (possibly the global one) could be resolved
-		self.resolvedApiFunction = sfunc
-		if sres ~= nil then --apparently it was the global one, and we received a 'blank argument'
-			self:setBlankArgument(sres)
+	if rData ~= nil and rData.func ~= nil then --function (possibly the global one) could be resolved
+		self.resolvedApiFunction = rData.func
+		self.moduleAccessTable = rData.accessTable
+		if rData.blankArg ~= nil then --apparently it was the global one, and we received a 'blank argument'
+			self:setBlankArgument(rData.blankArg)
 			self.realApiFunctionName = GLOBAL_API_FUNCTION_NAME
 		else --resolved without blank argument but still potentially the global function, hence the _or_ construction
 			if self:getRequestedApiFunction() ~= nil then
@@ -155,38 +167,19 @@ function M.new(postData, debug)
 		end
 	else
 		--instead of throwing an error, save the message for handle() which is expected to return a response anyway
-		self.resolutionError = sres
+		self.resolutionError = errMsg
 	end
 	
 	
 	return self
 end
 
---returns either GET or POST or CMDLINE
-function M:getRequestMethod()
-	return self.requestMethod
-end
-
-function M:getRequestedApiModule()
-	return self.requestedApiModule
-end
-
-function M:getRequestedApiFunction()
-	return self.requestedApiFunction
-end
-
-function M:getRealApiFunctionName()
-	return self.realApiFunctionName
-end
-
-function M:getBlankArgument()
-	return self.blankArgument
-end
-
-function M:setBlankArgument(arg)
-	self.blankArgument = arg
-end
-
+function M:getRequestMethod() return self.requestMethod end --returns either GET or POST or CMDLINE
+function M:getRequestedApiModule() return self.requestedApiModule end
+function M:getRequestedApiFunction() return self.requestedApiFunction end
+function M:getRealApiFunctionName() return self.realApiFunctionName end
+function M:getBlankArgument() return self.blankArgument end
+function M:setBlankArgument(arg) self.blankArgument = arg end
 function M:getRemoteHost() return self.remoteHost or "" end
 function M:getRemotePort() return self.remotePort or 0 end
 function M:getUserAgent() return self.userAgent or "" end
@@ -219,13 +212,19 @@ function M:getPathData()
 	return self.pathArgs
 end
 
-
 --returns either a response object+nil, or response object+errmsg
 function M:handle()
 	local modname = self:getRequestedApiModule()
 	local resp = ResponseClass.new(self)
 	
 	if (self.resolvedApiFunction ~= nil) then --we found a function (possible the global function)
+		--check access type
+		local accessText = self.moduleAccessTable[self.realApiFunctionName]
+		if not matchRequestMethod(accessText, self.requestMethod) then
+			resp:setError("function '" .. modname .. "/" .. self.realApiFunctionName .. "' requires different request method ('" .. accessText .. "')")
+			return resp, "incorrect access method (" .. accessText .. " != " .. self.requestMethod .. ")"
+		end
+		
 		--invoke the function
 		local ok, r
 		if config.DEBUG_PCALLS then ok, r = true, self.resolvedApiFunction(self, resp)

src/rest/response.lua

@@ -1,4 +1,4 @@
-local JSON = (loadfile "util/JSON.lua")()
+local JSON = require("util/JSON")
 local config = require("config")
 
 local M = {}
@@ -6,6 +6,9 @@ M.__index = M
 
 local REQUEST_ID_ARGUMENT = "rq_id"
 
+M.httpStatusCode, M.httpStatusText = nil, nil
+
+
 setmetatable(M, {
 	__call = function(cls, ...)
 		return cls.new(...)
@@ -16,7 +19,8 @@ setmetatable(M, {
 function M.new(requestObject)
 	local self = setmetatable({}, M)
 	
-	self.body = {status = nil, data = {}}
+	self.body = { status = nil, data = {} }
+	self:setHttpStatus(200, "OK")
 	
 	if requestObject ~= nil then
 		local rqId = requestObject:get(REQUEST_ID_ARGUMENT)
@@ -31,6 +35,11 @@ function M.new(requestObject)
 	return self
 end
 
+function M:setHttpStatus(code, text)
+	if code ~= nil then self.httpStatusCode = code end
+	if text ~= nil then self.httpStatusText = text end
+end
+
 function M:setSuccess(msg)
 	self.body.status = "success"
 	if msg ~= "" then self.body.msg = msg end
@@ -44,6 +53,8 @@ end
 function M:setError(msg)
 	self.body.status = "error"
 	if msg ~= "" then self.body.msg = msg end
+	
+	self:addData("more_info", "http://doodle3d.nl/wiki/wiki/communication-api")
 end
 
 --NOTE: with this method, to add nested data, it is necessary to precreate the table and add it with its root key
@@ -57,6 +68,8 @@ function M:serializeAsJson()
 end
 
 function M:send()
+	io.write("Status: " .. self.httpStatusCode .. " " .. self.httpStatusText .. "\r\n")
+	io.write ("Content-type: text/plain\r\n\r\n")
 	print(self:serializeAsJson())
 end
 

src/util/utils.lua

@@ -2,11 +2,14 @@ local uci = require("uci").cursor()
 
 local M = {}
 
-function string:split(sep)
-        local sep, fields = sep or ":", {}
-        local pattern = string.format("([^%s]+)", sep)
-        self:gsub(pattern, function(c) fields[#fields+1] = c end)
-        return fields
+function string:split(div)
+	local div, pos, arr = div or ":", 0, {}
+	for st,sp in function() return self:find(div, pos, true) end do
+		table.insert(arr, self:sub(pos, st - 1))
+		pos = sp + 1
+	end
+	table.insert(arr, self:sub(pos))
+	return arr
 end
 
 function M.toboolean(s)