diff options
Diffstat (limited to 'lib/support/share/socket/http.lua')
| -rw-r--r-- | lib/support/share/socket/http.lua | 350 |
1 files changed, 350 insertions, 0 deletions
diff --git a/lib/support/share/socket/http.lua b/lib/support/share/socket/http.lua new file mode 100644 index 0000000..ad8db1e --- /dev/null +++ b/lib/support/share/socket/http.lua @@ -0,0 +1,350 @@ +----------------------------------------------------------------------------- +-- HTTP/1.1 client support for the Lua language. +-- LuaSocket toolkit. +-- Author: Diego Nehab +-- RCS ID: $Id: http.lua,v 1.71 2007/10/13 23:55:20 diego Exp $ +----------------------------------------------------------------------------- + +----------------------------------------------------------------------------- +-- Declare module and import dependencies +------------------------------------------------------------------------------- +local socket = require("socket") +local url = require("socket.url") +local ltn12 = require("ltn12") +local mime = require("mime") +local string = require("string") +local base = _G +local table = require("table") +module("socket.http") + +----------------------------------------------------------------------------- +-- Program constants +----------------------------------------------------------------------------- +-- connection timeout in seconds +TIMEOUT = 60 +-- default port for document retrieval +PORT = 80 +-- user agent field sent in request +USERAGENT = socket._VERSION + +----------------------------------------------------------------------------- +-- 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 base.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 = base.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 base.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 open(host, port, create) + -- create socket with user connect function, or with default + local c = socket.try((create or socket.tcp)()) + local h = base.setmetatable({ c = c }, metat) + -- create finalized try + h.try = socket.newtry(function() h:close() end) + -- set timeout before connecting + h.try(c:settimeout(TIMEOUT)) + h.try(c:connect(host, port or 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(headers) + local h = "\r\n" + for i, v in base.pairs(headers) do + h = i .. ": " .. 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 = 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 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(base.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 = base.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 base.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 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 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 lower = { + ["user-agent"] = USERAGENT, + ["host"] = reqt.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 .. ":" .. reqt.password)) + end + -- override with user headers + for i,v in base.pairs(reqt.headers or lower) do + lower[string.lower(i)] = v + end + return lower +end + +-- default url parts +local default = { + host = "", + port = PORT, + 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 base.pairs(reqt) do nreqt[i] = v end + if nreqt.port == "" then nreqt.port = 80 end + socket.try(nreqt.host and nreqt.host ~= "", + "invalid host '" .. base.tostring(nreqt.host) .. "'") + -- compute uri if user hasn't overriden + nreqt.uri = reqt.uri or adjusturi(nreqt) + -- ajust host and port if there is a proxy + nreqt.host, nreqt.port = adjustproxy(nreqt) + -- adjust headers in request + nreqt.headers = adjustheaders(nreqt) + return nreqt +end + +local function shouldredirect(reqt, code, headers) + return headers.location and + string.gsub(headers.location, "%s", "") ~= "" and + (reqt.redirect ~= false) and + (code == 301 or code == 302) and + (not reqt.method or reqt.method == "GET" or reqt.method == "HEAD") + and (not reqt.nredirects or reqt.nredirects < 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 + +function tredirect(reqt, location) + local result, code, headers, status = trequest { + -- the RFC says the redirect URL has to be absolute, but some + -- servers do not respect that + url = url.absolute(reqt.url, location), + source = reqt.source, + sink = reqt.sink, + headers = reqt.headers, + proxy = reqt.proxy, + 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 + +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 = 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 + 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 + +local function srequest(u, b) + local t = {} + local reqt = { + url = u, + sink = ltn12.sink.table(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 + local code, headers, status = socket.skip(1, trequest(reqt)) + return table.concat(t), code, headers, status +end + +request = socket.protect(function(reqt, body) + if base.type(reqt) == "string" then return srequest(reqt, body) + else return trequest(reqt) end +end) |