Cors Error

[lesquive]

Hello!

I'm having issues with a Cors error being generated on by browser when I attempt to access Milua using a React client on local host. I'm unable to find any documentation on how to fix this. Any ideas?

This is my current script:

local app = require "milua"
local http = require("socket.http")
local ltn12 = require("ltn12")
local cjson = require("cjson")

local config = dofile("config.lua")
local openaiApiKey = config.openaiApiKey

-- API endpoint
local apiUrl = "https://api.openai.com/v1/chat/completions"

app.add_handler(
    "POST",
    "/openai",
    function(captures, query, headers, body)

        if headers["method"] == "OPTIONS" then
            return "", 200, {
                ["Access-Control-Allow-Origin"] = "*", -- Allow requests from any origin
                ["Access-Control-Allow-Methods"] = "POST, OPTIONS", -- Allow POST and OPTIONS methods
                ["Access-Control-Allow-Headers"] = "Content-Type, Authorization" -- Allow specified headers
            }
        end

        -- Parse JSON from the request body
        local requestData = {
            model = "gpt-3.5-turbo",
            messages = {{role = "user", content = cjson.decode(body).content}},
            temperature = 0.7
        }

        print("Request:", requestData)

        -- Convert Lua table to JSON
        local requestBody = cjson.encode(requestData)

        print("RequestBB:", requestBody)

        -- Request headers
        local requestHeaders = {
            ["Content-Type"] = "application/json",
            ["Authorization"] = "Bearer " .. openaiApiKey
        }

        -- Perform HTTP request
        local response = {}
        local _, statusCode, _, _ = http.request{
            url = apiUrl,
            method = "POST",
            headers = requestHeaders,
            source = ltn12.source.string(requestBody),
            sink = ltn12.sink.table(response)
        }

        -- Check the response
        if statusCode == 200 then
            print("Made it here!")
            local responseBody = table.concat(response)
            print("responseBody", responseBody)
            return responseBody 
        else
            return "Error"
        end
    end
)

app.start()

The error message I get:

My client is just doing a POST via axios:

const response = await axios.post("http://localhost:8800/openai", {
        content: input,
      });

[lesquive]

Update, I was able to fix the code with the following:

local app = require "milua"
local http = require("socket.http")
local ltn12 = require("ltn12")
local cjson = require("cjson")

-- Your OpenAI API key
local config = dofile("config.lua")
local openaiApiKey = config.openaiApiKey

-- API endpoint
local apiUrl = "https://api.openai.com/v1/chat/completions"

-- Define a handler for the OPTIONS method
app.add_handler(
    "OPTIONS",
    "/openai",
    function(captures, query, headers, body)

        -- Respond to preflight requests
        return "", {
            ["Access-Control-Allow-Origin"] = "*", -- Allow requests from any origin
            ["Access-Control-Allow-Methods"] = "POST, OPTIONS", -- Allow POST and OPTIONS methods
            ["Access-Control-Allow-Headers"] = "Content-Type, Authorization" -- Allow specified headers
        }
    end
)

-- Define a handler for the "/openai" endpoint
app.add_handler(
    "POST",
    "/openai",
    function(captures, query, headers, body)
        -- Parse JSON from the request body
        local requestData = {
            model = "gpt-3.5-turbo",
            messages = {{role = "user", content = cjson.decode(body).content}},
            temperature = 0.7
        }

        print("Request:", requestData)

        -- Convert Lua table to JSON
        local requestBody = cjson.encode(requestData)

        print("RequestBB:", requestBody)

        -- Request headers
        local requestHeaders = {
            ["Content-Type"] = "application/json",
            ["Authorization"] = "Bearer " .. openaiApiKey
        }

        -- Perform HTTP request
        local response = {}
        local _, statusCode, _, _ = http.request{
            url = apiUrl,
            method = "POST",
            headers = requestHeaders,
            source = ltn12.source.string(requestBody),
            sink = ltn12.sink.table(response)
        }

        -- Check the response
        if statusCode == 200 then
            print("Made it here!")
            local responseBody = table.concat(response)
            print("responseBody", responseBody)
            return responseBody, {
                ["Access-Control-Allow-Origin"] = "*", -- Allow requests from any origin
                ["Access-Control-Allow-Methods"] = "POST, OPTIONS", -- Allow POST and OPTIONS methods
                ["Access-Control-Allow-Headers"] = "Content-Type, Authorization" -- Allow specified headers
            } 
        else
            return "Error", {
                ["Access-Control-Allow-Origin"] = "*", -- Allow requests from any origin
                ["Access-Control-Allow-Methods"] = "POST, OPTIONS", -- Allow POST and OPTIONS methods
                ["Access-Control-Allow-Headers"] = "Content-Type, Authorization" -- Allow specified headers
            }
        end
    end
)

-- Start the application
app.start()

Not sure if its the best solution, but it works!

[MiguelMJ]

Glad you found a solution!
CORS errors compete the browser and the configuration of the responses, not the framework itself.
Check this as reference.
Thanks for reporting anyways!