Files
Techmino/Zframework/websocket.lua
2021-02-13 13:55:51 +08:00

145 lines
3.6 KiB
Lua

--[[
websocket client pure lua implement for love2d
by flaribbit
usage:
local client = require("websocket").new()
client:settimeout(1)
client:connect("127.0.0.1", 5000)
client:settimeout(0)
client:send("hello from love2d")
res, opcode = client:read()
print(res)
client:close()
]]
-- local debug_print=print
local socket = require"socket"
local bit = require"bit"
local band, bor, bxor = bit.band, bit.bor, bit.bxor
local shl, shr = bit.lshift, bit.rshift
local OPCODES = {
CONTINUE=0,
TEXT =1,
BINARY =2,
CLOSE =8,
PING =9,
PONG =10,
}
local _M = {
OPCODES = OPCODES,
}
_M.__index = _M
function _M.new()
local m = {socket = socket.tcp()}
setmetatable(m, _M)
return m
end
local seckey = "osT3F7mvlojIvf3/8uIsJQ=="
function _M:connect(host, port, path)
local SOCK = self.socket
local res, err = SOCK:connect(host, port)
if res~=1 then return res, err end
-- debug_print("[handshake] connected")
-- WebSocket handshake
res, err = SOCK:send("GET "..(path or"/").." HTTP/1.1\r\nHost: "..host..":"..port.."\r\nConnection: Upgrade\r\nUpgrade: websocket\r\nSec-WebSocket-Version: 13\r\nSec-WebSocket-Key: "..seckey.."\r\n\r\n")
repeat res = SOCK:receive("*l") until res==""
-- debug_print("[handshake] succeed")
end
local function send(SOCK, opcode, message)
local mask_key = {1, 14, 5, 14}
-- message type
SOCK:send(string.char(bor(0x80, opcode)))
if message==nil then
SOCK:send(string.char(0x80, unpack(mask_key)))
return 0
end
-- length
local length = #message
-- debug_print("[encode] message length: "..length)
if length>65535 then
SOCK:send(string.char(bor(127, 0x80), 0, 0, 0, 0,
band(shr(length, 24), 0xff),
band(shr(length, 16), 0xff),
band(shr(length, 8), 0xff),
band(length, 0xff)))
elseif length>125 then
SOCK:send(string.char(bor(126, 0x80),
band(shr(length, 8), 0xff),
band(length, 0xff)))
else
SOCK:send(string.char(bor(length, 0x80)))
end
-- debug_print("[encode] masking")
SOCK:send(string.char(unpack(mask_key)))
local msgbyte = {message:byte(1, length)}
for i = 1, length do
msgbyte[i] = bxor(msgbyte[i], mask_key[(i-1)%4+1])
end
return SOCK:send(string.char(unpack(msgbyte)))
-- debug_print("[encode] end")
end
function _M:send(message)
send(self.socket, OPCODES.BINARY, message)
end
function _M:ping(message)
send(self.socket, OPCODES.PING, message)
end
function _M:pong(message)
send(self.socket, OPCODES.PONG, message)
end
function _M:read()
-- byte 0-1
local SOCK = self.socket
local res, err = SOCK:receive(2)
if res==nil then return res, err end
-- local flag_FIN = res:byte()>=0x80
local OPCODE = band(res:byte(), 0x0f)
-- local flag_MASK = res:byte(2)>=0x80
-- debug_print("[decode] FIN="..tostring(flag_FIN)..", OPCODE="..OPCODE..", MASK="..tostring(flag_MASK))
-- length
local byte = res:byte(2)
local length = band(byte, 0x7f)
if length==126 then
res = SOCK:receive(2)
local b1, b2 = res:byte(1, 2)
length = shl(b1, 8) + b2
elseif length==127 then
res = SOCK:receive(8)
local b = {res:byte(1, 8)}
length = shl(b[5], 32) + shl(b[6], 24) + shl(b[7], 8) + b[8]
end
-- debug_print("[decode] message length: "..length)
-- data
res = SOCK:receive(length)
if OPCODE==OPCODES.PING then
self:pong(res)
elseif OPCODE==OPCODES.CLOSE then
self:close()
end
-- debug_print("[decode] string length: "..#res)
-- debug_print("[decode] end")
return res, OPCODE
end
function _M:close() self.socket:close() end
function _M:settimeout(t) self.socket:settimeout(t) end
return _M