Net

Built-in library for network access

Example usage

local net = require("@lune/net")
local serde = require("@lune/serde")

-- Sending a web request
local response = net.request("https://www.google.com")
print(response.ok)
print(response.statusCode, response.statusMessage)
print(response.headers)

-- Using a JSON web API
local response = net.request({
  url = "https://dummyjson.com/products/add",
  method = "POST",
  headers = { ["Content-Type"] = "application/json" },
  body = serde.encode("json", {
    title = "Cool Pencil",
  })
})
local product = serde.decode("json", response.body)
print(product.id, "-", product.title)

-- Starting up an http server
net.serve(8080, function(request)
  return {
    status = 200,
    body = "Echo:\n" .. request.body,
  }
end)

-- Writing to a plain TCP stream
local conn = net.tcp.connect("example.com", 80)

conn:write("GET / HTTP/1.1\r\nHost: example.com\r\n\r\n")

Functions

request

Sends an HTTP request using the given url and / or parameters, and returns a dictionary that describes the response received.

Only throws an error if a miscellaneous network or I/O error occurs, never for unsuccessful status codes.

Parameters

config The URL or request config to use

Returns

A dictionary representing the response for the request

socket

Connects to a web socket at the given URL.

Throws an error if the server at the given URL does not support web sockets, or if a miscellaneous network or I/O error occurs.

Parameters

url The URL to connect to

Returns

A web socket handle

serve

Creates an HTTP server that listens on the given port.

This will not block and will keep listening for requests on the given port until the stop function on the returned ServeHandle has been called.

Parameters

port The port to use for the server
handlerOrConfig The handler function or config to use for the server

Returns

ServeHandle

urlEncode

Encodes the given string using URL encoding.

Parameters

s The string to encode
binary If the string should be treated as binary data and/or is not valid utf-8. Defaults to false

Returns

The encoded string

urlDecode

Decodes the given string using URL decoding.

Parameters

s The string to decode
binary If the string should be treated as binary data and/or is not valid utf-8. Defaults to false

Returns

The decoded string

Types

FetchParamsOptions

Extra options for FetchParams.

This is a dictionary that may contain one or more of the following values:

decompress - If the request body should be automatically decompressed when possible. Defaults to true

FetchParams

Parameters for sending network requests with net.request.

This is a dictionary that may contain one or more of the following values:

url - The URL to send a request to. This is always required
method - The HTTP method verb, such as "GET", "POST", "PATCH", "PUT", or "DELETE". Defaults to "GET"
body - The request body
query - A table of key-value pairs representing query parameters in the request path
headers - A table of key-value pairs representing headers
options - Extra options for things such as automatic decompression of response bodies

FetchResponse

Response type for sending network requests with net.request.

This is a dictionary containing the following values:

ok - If the status code is a canonical success status code, meaning within the range 200 -> 299
statusCode - The status code returned for the request
statusMessage - The canonical status message for the returned status code, such as "Not Found" for status code 404
headers - A table of key-value pairs representing headers
body - The request body, or an empty string if one was not given

ServeRequest

Data type for requests in net.serve.

This is a dictionary containing the following values:

path - The path being requested, relative to the root. Will be / if not specified
query - A table of key-value pairs representing query parameters in the request path
method - The HTTP method verb, such as "GET", "POST", "PATCH", "PUT", or "DELETE". Will always be uppercase
headers - A table of key-value pairs representing headers
body - The request body, or an empty string if one was not given

ServeResponse

Response type for requests in net.serve.

This is a dictionary that may contain one or more of the following values:

status - The status code for the request, in the range 100 -> 599
headers - A table of key-value pairs representing headers
body - The response body

ServeConfig

Configuration for net.serve.

This may contain one of or more of the following values:

address for setting the IP address to serve from. Defaults to the loopback interface (http://localhost).
handleRequest for handling normal http requests, equivalent to just passing a function to net.serve
handleWebSocket for handling web socket requests, which will receive a WebSocket object as its first and only parameter

When setting address, the handleRequest callback must also be defined.

Example Usage

net.serve(8080, {
  address = "http://0.0.0.0",
  handleRequest = function(request)
    return {
      status = 200,
      body = "Echo:\n" .. request.body,
    }
  end
})

ServeHandle

A handle to a currently running web server, containing a single stop function to gracefully shut down the web server.

WebSocket

A reference to a web socket connection.

The web socket may be in either an “open” or a “closed” state, changing its current behavior.

When open:

Any function on the socket such as send, next or close can be called without erroring
next can be called to yield until the next message is received or the socket becomes closed

When closed:

next will no longer return any message(s) and instead instantly return nil
send will throw an error stating that the socket has been closed

Once the websocket has been closed, closeCode will no longer be nil, and will be populated with a close code according to the WebSocket specification. This will be an integer between 1000 and 4999, where 1000 is the canonical code for normal, error-free closure.

TcpConfig

Configuration options for a TCP stream.

Example Usage

-- Plain TCP connection
local stream = net.tcp.connect("example.com", 80)

-- TLS connection (shorthand)
local stream = net.tcp.connect("example.com", 443, true)

-- TLS connection (explicit config)
local stream = net.tcp.connect("example.com", 443, { tls = true })

-- Connection with custom TTL
local stream = net.tcp.connect("192.168.1.100", 8080, {
  tls = false,
  ttl = 128
})

TcpStream

A plain TCP stream, which may also be backed by a TLS connection.

Example Usage

local net = require("@lune/net")

local conn = net.tcp.connect("example.com", 80)

conn:write("GET / HTTP/1.1\r\nHost: example.com\r\n\r\n")

local response = conn:read()
print(response)

conn:close()

Tcp

TCP primitives for the net library

Provides low-level TCP socket functionality for creating custom network protocols or communicating with services that don’t use HTTP - for all HTTP usage, please use the request and serve HTTP functions instead.

Functions

connect

Connects to the given host and port, returning a TcpStream.

For additional details, see the documentation for the TcpConfig and TcpStream types.

Will throw an error if the connection fails.

Parameters

host The host to connect to, either a DNS name or IP address
port The port to connect to
config The optional configuration to use for the stream

Returns

A connected TcpStream ready for reading and writing