Remove global PORT. Fix https redirect.

doc/http.html

@@ -112,12 +112,15 @@ the HTTP module:
 </p>
 
 <ul>
-<li> <tt>PORT</tt>: default port used for connections; 
 <li> <tt>PROXY</tt>: default proxy used for connections;
 <li> <tt>TIMEOUT</tt>: sets the timeout for all I/O operations;
 <li> <tt>USERAGENT</tt>: default user agent reported to server.
 </ul>
 
+<p class=note id="post">
+Note: These constants are global. Changing them will also
+change the behavior other code that might be using LuaSocket.
+</p>
 
 <!-- http.request ++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->
 

src/http.lua

@@ -23,11 +23,14 @@ local _M = socket.http
 -----------------------------------------------------------------------------
 -- connection timeout in seconds
 _M.TIMEOUT = 60
--- default port for document retrieval
-_M.PORT = 80
 -- user agent field sent in request
 _M.USERAGENT = socket._VERSION
 
+-- supported schemes
+local SCHEMES = { ["http"] = true }
+-- default port for document retrieval
+local PORT = 80
+
 -----------------------------------------------------------------------------
 -- Reads MIME headers from a connection, unfolding where needed
 -----------------------------------------------------------------------------
@@ -114,7 +117,7 @@ function _M.open(host, port, create)
     h.try = socket.newtry(function() h:close() end)
     -- set timeout before connecting
     h.try(c:settimeout(_M.TIMEOUT))
-    h.try(c:connect(host, port or _M.PORT))
+    h.try(c:connect(host, port or PORT))
     -- here everything worked
     return h
 end
@@ -240,7 +243,7 @@ end
 -- default url parts
 local default = {
     host = "",
-    port = _M.PORT,
+    port = PORT,
     path ="/",
     scheme = "http"
 }
@@ -250,9 +253,10 @@ local function adjustrequest(reqt)
     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) .. "'")
+    if nreqt.port == "" then nreqt.port = PORT end
+    if not (nreqt.host and nreqt.host ~= "") then
+        socket.try(nil, "invalid host '" .. base.tostring(nreqt.host) .. "'")
+    end
     -- compute uri if user hasn't overriden
     nreqt.uri = reqt.uri or adjusturi(nreqt)
     -- adjust headers in request
@@ -263,9 +267,13 @@ local function adjustrequest(reqt)
 end
 
 local function shouldredirect(reqt, code, headers)
-    return headers.location and
-           string.gsub(headers.location, "%s", "") ~= "" and
-           (reqt.redirect ~= false) and
+    local location = headers.location
+    if not location then return false end
+    location = string.gsub(location, "%s", "")
+    if location == "" then return false end
+    local scheme = string.match(location, "^([%w][%w%+%-%.]*)%:")
+    if scheme and not SCHEMES[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 (not reqt.nredirects or reqt.nredirects < 5)