409 lines
14 KiB
Lua
409 lines
14 KiB
Lua
-----------------------------------------------------------------------------
|
|
-- HTTP/1.1 client support for the Lua language.
|
|
-- LuaSocket toolkit.
|
|
-- Author: Diego Nehab
|
|
-----------------------------------------------------------------------------
|
|
|
|
-----------------------------------------------------------------------------
|
|
-- Declare module and import dependencies
|
|
-------------------------------------------------------------------------------
|
|
socket.http = {}
|
|
local _M = socket.http
|
|
|
|
-----------------------------------------------------------------------------
|
|
-- Program constants
|
|
-----------------------------------------------------------------------------
|
|
-- connection timeout in seconds
|
|
_M.TIMEOUT = 60
|
|
-- user agent field sent in request
|
|
_M.USERAGENT = socket._VERSION
|
|
|
|
-- supported schemes and their particulars
|
|
local SCHEMES = {
|
|
http = {
|
|
port = 80
|
|
, create = function(t)
|
|
return socket.tcp end }
|
|
, https = {
|
|
port = 443
|
|
, create = function(t)
|
|
return https.tcp(t) end }}
|
|
|
|
-- default scheme and port for document retrieval
|
|
local SCHEME = 'http'
|
|
local PORT = SCHEMES[SCHEME].port
|
|
-----------------------------------------------------------------------------
|
|
-- Reads MIME headers from a connection, unfolding where needed
|
|
-----------------------------------------------------------------------------
|
|
local function receiveheaders(sock, headers)
|
|
local line, name, value, err
|
|
headers = headers or {}
|
|
-- get first line
|
|
line, err = sock:receive()
|
|
if err then return nil, err end
|
|
-- headers go until a blank line is found
|
|
while line ~= "" do
|
|
-- get field-name and value
|
|
name, value = socket.skip(2, string.find(line, "^(.-):%s*(.*)"))
|
|
if not (name and value) then return nil, "malformed reponse headers" end
|
|
name = string.lower(name)
|
|
-- get next line (value might be folded)
|
|
line, err = sock:receive()
|
|
if err then return nil, err end
|
|
-- unfold any folded values
|
|
while string.find(line, "^%s") do
|
|
value = value .. line
|
|
line = sock:receive()
|
|
if err then return nil, err end
|
|
end
|
|
-- save pair in table
|
|
if headers[name] then headers[name] = headers[name] .. ", " .. value
|
|
else headers[name] = value end
|
|
end
|
|
return headers
|
|
end
|
|
|
|
-----------------------------------------------------------------------------
|
|
-- Extra sources and sinks
|
|
-----------------------------------------------------------------------------
|
|
socket.sourcet["http-chunked"] = function(sock, headers)
|
|
return setmetatable({
|
|
getfd = function() return sock:getfd() end,
|
|
dirty = function() return sock:dirty() end
|
|
}, {
|
|
__call = function()
|
|
-- get chunk size, skip extention
|
|
local line, err = sock:receive()
|
|
if err then return nil, err end
|
|
local size = tonumber(string.gsub(line, ";.*", ""), 16)
|
|
if not size then return nil, "invalid chunk size" end
|
|
-- was it the last chunk?
|
|
if size > 0 then
|
|
-- if not, get chunk and skip terminating CRLF
|
|
local chunk, err, part = sock:receive(size)
|
|
if chunk then sock:receive() end
|
|
return chunk, err
|
|
else
|
|
-- if it was, read trailers into headers table
|
|
headers, err = receiveheaders(sock, headers)
|
|
if not headers then return nil, err end
|
|
end
|
|
end
|
|
})
|
|
end
|
|
|
|
socket.sinkt["http-chunked"] = function(sock)
|
|
return setmetatable({
|
|
getfd = function() return sock:getfd() end,
|
|
dirty = function() return sock:dirty() end
|
|
}, {
|
|
__call = function(self, chunk, err)
|
|
if not chunk then return sock:send("0\r\n\r\n") end
|
|
local size = string.format("%X\r\n", string.len(chunk))
|
|
return sock:send(size .. chunk .. "\r\n")
|
|
end
|
|
})
|
|
end
|
|
|
|
-----------------------------------------------------------------------------
|
|
-- Low level HTTP API
|
|
-----------------------------------------------------------------------------
|
|
local metat = { __index = {} }
|
|
|
|
function _M.open(host, port, create)
|
|
-- create socket with user connect function, or with default
|
|
local c = socket.try(create())
|
|
local h = setmetatable({ c = c }, metat)
|
|
-- create finalized try
|
|
h.try = socket.newtry(function() h:close() end)
|
|
-- set timeout before connecting
|
|
h.try(c:settimeout(_M.TIMEOUT))
|
|
h.try(c:connect(host, port))
|
|
-- here everything worked
|
|
return h
|
|
end
|
|
|
|
function metat.__index:sendrequestline(method, uri)
|
|
local reqline = string.format("%s %s HTTP/1.1\r\n", method or "GET", uri)
|
|
return self.try(self.c:send(reqline))
|
|
end
|
|
|
|
function metat.__index:sendheaders(tosend)
|
|
local canonic = headers.canonic
|
|
local h = "\r\n"
|
|
for f, v in pairs(tosend) do
|
|
h = (canonic[f] or f) .. ": " .. v .. "\r\n" .. h
|
|
end
|
|
self.try(self.c:send(h))
|
|
return 1
|
|
end
|
|
|
|
function metat.__index:sendbody(headers, source, step)
|
|
source = source or ltn12.source.empty()
|
|
step = step or ltn12.pump.step
|
|
-- if we don't know the size in advance, send chunked and hope for the best
|
|
local mode = "http-chunked"
|
|
if headers["content-length"] then mode = "keep-open" end
|
|
return self.try(ltn12.pump.all(source, socket.sink(mode, self.c), step))
|
|
end
|
|
|
|
function metat.__index:receivestatusline()
|
|
local status,ec = self.try(self.c:receive(5))
|
|
-- identify HTTP/0.9 responses, which do not contain a status line
|
|
-- this is just a heuristic, but is what the RFC recommends
|
|
if status ~= "HTTP/" then
|
|
if ec == "timeout" then
|
|
return 408
|
|
end
|
|
return nil, status
|
|
end
|
|
-- otherwise proceed reading a status line
|
|
status = self.try(self.c:receive("*l", status))
|
|
local code = socket.skip(2, string.find(status, "HTTP/%d*%.%d* (%d%d%d)"))
|
|
return self.try(tonumber(code), status)
|
|
end
|
|
|
|
function metat.__index:receiveheaders()
|
|
return self.try(receiveheaders(self.c))
|
|
end
|
|
|
|
function metat.__index:receivebody(headers, sink, step)
|
|
sink = sink or ltn12.sink.null()
|
|
step = step or ltn12.pump.step
|
|
local length = tonumber(headers["content-length"])
|
|
local t = headers["transfer-encoding"] -- shortcut
|
|
local mode = "default" -- connection close
|
|
if t and t ~= "identity" then mode = "http-chunked"
|
|
elseif tonumber(headers["content-length"]) then mode = "by-length" end
|
|
return self.try(ltn12.pump.all(socket.source(mode, self.c, length),
|
|
sink, step))
|
|
end
|
|
|
|
function metat.__index:receive09body(status, sink, step)
|
|
local source = ltn12.source.rewind(socket.source("until-closed", self.c))
|
|
source(status)
|
|
return self.try(ltn12.pump.all(source, sink, step))
|
|
end
|
|
|
|
function metat.__index:close()
|
|
return self.c:close()
|
|
end
|
|
|
|
-----------------------------------------------------------------------------
|
|
-- High level HTTP API
|
|
-----------------------------------------------------------------------------
|
|
local function adjusturi(reqt)
|
|
local u = reqt
|
|
-- if there is a proxy, we need the full url. otherwise, just a part.
|
|
if not reqt.proxy and not _M.PROXY then
|
|
u = {
|
|
path = socket.try(reqt.path, "invalid path 'nil'"),
|
|
params = reqt.params,
|
|
query = reqt.query,
|
|
fragment = reqt.fragment
|
|
}
|
|
end
|
|
return url.build(u)
|
|
end
|
|
|
|
local function adjustproxy(reqt)
|
|
local proxy = reqt.proxy or _M.PROXY
|
|
if proxy then
|
|
proxy = url.parse(proxy)
|
|
return proxy.host, proxy.port or 3128
|
|
else
|
|
return reqt.host, reqt.port
|
|
end
|
|
end
|
|
|
|
local function adjustheaders(reqt)
|
|
-- default headers
|
|
local host = reqt.host
|
|
local port = tostring(reqt.port)
|
|
if port ~= tostring(SCHEMES[reqt.scheme].port) then
|
|
host = host .. ':' .. port end
|
|
local lower = {
|
|
["user-agent"] = _M.USERAGENT,
|
|
["host"] = host,
|
|
["connection"] = "close, TE",
|
|
["te"] = "trailers"
|
|
}
|
|
-- if we have authentication information, pass it along
|
|
if reqt.user and reqt.password then
|
|
lower["authorization"] =
|
|
"Basic " .. (mime.b64(reqt.user .. ":" ..
|
|
url.unescape(reqt.password)))
|
|
end
|
|
-- if we have proxy authentication information, pass it along
|
|
local proxy = reqt.proxy or _M.PROXY
|
|
if proxy then
|
|
proxy = url.parse(proxy)
|
|
if proxy.user and proxy.password then
|
|
lower["proxy-authorization"] =
|
|
"Basic " .. (mime.b64(proxy.user .. ":" .. proxy.password))
|
|
end
|
|
end
|
|
-- override with user headers
|
|
for i,v in pairs(reqt.headers or lower) do
|
|
lower[string.lower(i)] = v
|
|
end
|
|
return lower
|
|
end
|
|
|
|
-- default url parts
|
|
local default = {
|
|
path ="/"
|
|
, scheme = "http"
|
|
}
|
|
|
|
local function adjustrequest(reqt)
|
|
-- parse url if provided
|
|
local nreqt = reqt.url and url.parse(reqt.url, default) or {}
|
|
-- explicit components override url
|
|
for i,v in pairs(reqt) do nreqt[i] = v end
|
|
-- default to scheme particulars
|
|
local schemedefs, host, port, method
|
|
= SCHEMES[nreqt.scheme], nreqt.host, nreqt.port, nreqt.method
|
|
if not nreqt.create then nreqt.create = schemedefs.create(nreqt) end
|
|
if not (port and port ~= '') then nreqt.port = schemedefs.port end
|
|
if not (method and method ~= '') then nreqt.method = 'GET' end
|
|
if not (host and host ~= "") then
|
|
socket.try(nil, "invalid host '" .. tostring(nreqt.host) .. "'")
|
|
end
|
|
-- compute uri if user hasn't overriden
|
|
nreqt.uri = reqt.uri or adjusturi(nreqt)
|
|
-- adjust headers in request
|
|
nreqt.headers = adjustheaders(nreqt)
|
|
-- ajust host and port if there is a proxy
|
|
nreqt.host, nreqt.port = adjustproxy(nreqt)
|
|
return nreqt
|
|
end
|
|
|
|
local function shouldredirect(reqt, code, headers)
|
|
local location = headers.location
|
|
if not location then return false end
|
|
location = string.gsub(location, "%s", "")
|
|
if location == "" then return false end
|
|
local scheme = url.parse(location).scheme
|
|
if scheme and (not SCHEMES[scheme]) then return false end
|
|
-- avoid https downgrades
|
|
if ('https' == reqt.scheme) and ('https' ~= scheme) then return false end
|
|
return (reqt.redirect ~= false) and
|
|
(code == 301 or code == 302 or code == 303 or code == 307) and
|
|
(not reqt.method or reqt.method == "GET" or reqt.method == "HEAD")
|
|
and ((false == reqt.maxredirects)
|
|
or ((reqt.nredirects or 0)
|
|
< (reqt.maxredirects or 5)))
|
|
end
|
|
|
|
local function shouldreceivebody(reqt, code)
|
|
if reqt.method == "HEAD" then return nil end
|
|
if code == 204 or code == 304 then return nil end
|
|
if code >= 100 and code < 200 then return nil end
|
|
return 1
|
|
end
|
|
|
|
-- forward declarations
|
|
local trequest, tredirect
|
|
|
|
--[[local]] function tredirect(reqt, location)
|
|
-- the RFC says the redirect URL has to be absolute, but some
|
|
-- servers do not respect that
|
|
local newurl = url.absolute(reqt.url, location)
|
|
-- if switching schemes, reset port and create function
|
|
if url.parse(newurl).scheme ~= reqt.scheme then
|
|
reqt.port = nil
|
|
reqt.create = nil end
|
|
-- make new request
|
|
local result, code, headers, status = trequest {
|
|
url = newurl,
|
|
source = reqt.source,
|
|
sink = reqt.sink,
|
|
headers = reqt.headers,
|
|
proxy = reqt.proxy,
|
|
maxredirects = reqt.maxredirects,
|
|
nredirects = (reqt.nredirects or 0) + 1,
|
|
create = reqt.create
|
|
}
|
|
-- pass location header back as a hint we redirected
|
|
headers = headers or {}
|
|
headers.location = headers.location or location
|
|
return result, code, headers, status
|
|
end
|
|
|
|
--[[local]] function trequest(reqt)
|
|
-- we loop until we get what we want, or
|
|
-- until we are sure there is no way to get it
|
|
local nreqt = adjustrequest(reqt)
|
|
local h = _M.open(nreqt.host, nreqt.port, nreqt.create)
|
|
-- send request line and headers
|
|
h:sendrequestline(nreqt.method, nreqt.uri)
|
|
h:sendheaders(nreqt.headers)
|
|
-- if there is a body, send it
|
|
if nreqt.source then
|
|
h:sendbody(nreqt.headers, nreqt.source, nreqt.step)
|
|
end
|
|
local code, status = h:receivestatusline()
|
|
-- if it is an HTTP/0.9 server, simply get the body and we are done
|
|
if not code then
|
|
h:receive09body(status, nreqt.sink, nreqt.step)
|
|
return 1, 200
|
|
elseif code == 408 then
|
|
return 1, code
|
|
end
|
|
local headers
|
|
-- ignore any 100-continue messages
|
|
while code == 100 do
|
|
headers = h:receiveheaders()
|
|
code, status = h:receivestatusline()
|
|
end
|
|
headers = h:receiveheaders()
|
|
-- at this point we should have a honest reply from the server
|
|
-- we can't redirect if we already used the source, so we report the error
|
|
if shouldredirect(nreqt, code, headers) and not nreqt.source then
|
|
h:close()
|
|
return tredirect(reqt, headers.location)
|
|
end
|
|
-- here we are finally done
|
|
if shouldreceivebody(nreqt, code) then
|
|
h:receivebody(headers, nreqt.sink, nreqt.step)
|
|
end
|
|
h:close()
|
|
return 1, code, headers, status
|
|
end
|
|
|
|
-- turns an url and a body into a generic request
|
|
local function genericform(u, b)
|
|
local t = {}
|
|
local reqt = {
|
|
url = u,
|
|
sink = ltn12.sink.table(t),
|
|
target = t
|
|
}
|
|
if b then
|
|
reqt.source = ltn12.source.string(b)
|
|
reqt.headers = {
|
|
["content-length"] = string.len(b),
|
|
["content-type"] = "application/x-www-form-urlencoded"
|
|
}
|
|
reqt.method = "POST"
|
|
end
|
|
return reqt
|
|
end
|
|
|
|
_M.genericform = genericform
|
|
|
|
local function srequest(u, b)
|
|
local reqt = genericform(u, b)
|
|
local _, code, headers, status = trequest(reqt)
|
|
return table.concat(reqt.target), code, headers, status
|
|
end
|
|
|
|
_M.request = socket.protect(function(reqt, body)
|
|
if type(reqt) == "string" then return srequest(reqt, body)
|
|
else return trequest(reqt) end
|
|
end)
|
|
|
|
_M.schemes = SCHEMES
|
|
return _M
|