cgilua.lua

cgi for lua, you can build your personal web site by lua

----------------------------------------------------------------------------
-- CGILua library.
--
-- @release $Id: cgilua.lua,v 1.46 2007/08/21 20:15:55 carregal Exp $
----------------------------------------------------------------------------

local _G, SAPI = _G, SAPI
local urlcode = require"cgilua.urlcode"
local lp = require"cgilua.lp"
local post = require"cgilua.post"
local lfs = require"lfs"
local debug = require"debug"
local assert, error, ipairs, select, tostring, type, unpack, xpcall = assert, error, ipairs, select, tostring, type, unpack, xpcall
local gsub, format, strfind, strlower, strsub = string.gsub, string.format, string.find, string.lower, string.sub
local setmetatable = setmetatable
local _open = io.open
local tinsert, tremove = table.insert, table.remove
local date = os.date
local seeall = package.seeall

lp.setoutfunc ("cgilua.put")
lp.setcompatmode (true)

module ("cgilua")

--
-- Internal state variables.
local default_errorhandler = debug.traceback
local errorhandler = default_errorhandler
local default_erroroutput = function (msg)

    if type(msg) ~= "string" and type(msg) ~= "number" then
        msg = format ("bad argument #1 to 'error' (string expected, got %s)", type(msg))
    end
  
	-- Logging error
	SAPI.Response.errorlog (msg)
	SAPI.Response.errorlog (" ")

	SAPI.Response.errorlog (SAPI.Request.servervariable"REMOTE_ADDR")
	SAPI.Response.errorlog (" ")

	SAPI.Response.errorlog (date())
	SAPI.Response.errorlog ("\n")

	-- Building user message
	SAPI.Response.contenttype ("text/html")
	msg = gsub (gsub (msg, "\n", "<br>\n"), "\t", "&nbsp;&nbsp;")
	SAPI.Response.write (msg)
end
local erroroutput = default_erroroutput
local default_maxfilesize = 512 * 1024
local maxfilesize = default_maxfilesize
local default_maxinput = 1024 * 1024
local maxinput = default_maxinput
script_path = false

_COPYRIGHT = "Copyright (C) 2003-2007 Kepler Project"
_DESCRIPTION = "CGILua is a tool for creating dynamic Web pages and manipulating input data from forms"
_VERSION = "CGILua 5.1.0"

--
-- Header functions

----------------------------------------------------------------------------
-- Sends a header.
-- @param header String with the header.
-- @param value String with the corresponding value.
----------------------------------------------------------------------------
header = SAPI.Response.header

----------------------------------------------------------------------------
-- Sends a Content-type header.
-- @param type String with the type of the header.
-- @param subtype String with the subtype of the header.
----------------------------------------------------------------------------
function contentheader (type, subtype)
	SAPI.Response.contenttype (type..'/'..subtype)
end

----------------------------------------------------------------------------
-- Sends the HTTP header "text/html".
----------------------------------------------------------------------------
function htmlheader()
	SAPI.Response.contenttype ("text/html")
end
local htmlheader = htmlheader

----------------------------------------------------------------------------
-- Sends an HTTP header redirecting the browser to another URL
-- @param url String with the URL.
-- @param args Table with the arguments (optional).
----------------------------------------------------------------------------
function redirect (url, args)
	if strfind(url,"^https?:") then
		local params=""
		if args then
			params = "?"..urlcode.encodetable(args)
		end
		return SAPI.Response.redirect(url..params)
	else
		return SAPI.Response.redirect(mkabsoluteurl(mkurlpath(url,args)))
	end
end

----------------------------------------------------------------------------
-- Returns a server variable
-- @param name String with the name of the server variable.
-- @return String with the value of the server variable.
----------------------------------------------------------------------------
servervariable = SAPI.Request.servervariable

----------------------------------------------------------------------------
-- Primitive error output function
-- @param msg String (or number) with the message.
-- @param level String with the error level (optional).
----------------------------------------------------------------------------
function errorlog (msg, level)
	local t = type(msg)
	if t == "string" or t == "number" then
		SAPI.Response.errorlog (msg, level)
	else
		error ("bad argument #1 to `cgilua.errorlog' (string expected, got "..t..")", 2)
	end
end

----------------------------------------------------------------------------
-- Converts all its arguments to strings before sending them to the server.
----------------------------------------------------------------------------
function print (...)
	local args = { ... }
	for i = 1, select("#",...) do
		args[i] = tostring(args[i])
	end
	SAPI.Response.write (unpack(args))
end

----------------------------------------------------------------------------
-- Function 'put' sends its arguments (basically strings of HTML text)
--  to the server
-- Its basic implementation is to use Lua function 'write', which writes
--  each of its arguments (strings or numbers) to file _OUTPUT (a file
--  handle initialized with the file descriptor for stdout)
-- @param s String (or number) with output.
----------------------------------------------------------------------------
put = SAPI.Response.write

----------------------------------------------------------------------------
-- Remove globals not allowed in CGILua scripts.
-- @param notallowed Array of Strings with the names to be removed.
----------------------------------------------------------------------------
function removeglobals (notallowed)
	for _, g in ipairs(notallowed) do
		if type(_G[g]) ~= "function" then
			_G[g] = nil
		else
			_G[g] = function()
				 error("Function '"..g.."' is not allowed in CGILua scripts.")
			end
		end
	end
end

----------------------------------------------------------------------------
-- Execute a script
--  If an error is found, Lua's error handler is called and this function
--  does not return
-- @param filename String with the name of the file to be processed.
-- @return The result of the execution of the file.
----------------------------------------------------------------------------
function doscript (filename)
	local res, err = _G.loadfile(filename)
	if not res then
		error (format ("Cannot execute `%s'. Exiting.\n%s", filename, err))
	else
		return res ()
	end
end

----------------------------------------------------------------------------
-- Execute the file if there is no "file error".
--  If an error is found, and it is not a "file error", Lua 'error'
--  is called and this function does not return
-- @param filename String with the name of the file to be processed.
-- @return The result of the execution of the file or nil (in case the
--	file does not exists or if it cannot be opened).
-- @return It could return an error message if the file cannot be opened.
----------------------------------------------------------------------------
function doif (filename)
	if not filename then return end    -- no file
	local f, err = _open(filename)
	if not f then return nil, err end    -- no file (or unreadable file)
	f:close()
	return doscript (filename)
end

---------------------------------------------------------------------------
-- Set the maximum "total" input size allowed (in bytes)
-- @param nbytes Number of the maximum size (in bytes) of the whole POST data.
---------------------------------------------------------------------------
function setmaxinput(nbytes)
	maxinput = nbytes
end

---------------------------------------------------------------------------
-- Set the maximum size for an "uploaded" file (in bytes)
-- Might be less or equal than maxinput.
-- @param nbytes Number of the maximum size (in bytes) of a file.
---------------------------------------------------------------------------
function setmaxfilesize(nbytes)
	maxfilesize = nbytes
end

----------------------------------------------------------------------------
-- Preprocess the content of a mixed HTML file and output a complete
--   HTML document ( a 'Content-type' header is inserted before the
--   preprocessed HTML )
-- @param filename String with the name of the file to be processed.
----------------------------------------------------------------------------
function handlelp (filename)
	htmlheader ()
	lp.include (filename)
end

----------------------------------------------------------------------------
-- Builds a handler that sends a header and the contents of the given file.
-- Sends the contents of the file to the output without processing it.
-- @param type String with the type of the header.
-- @param subtype String with the subtype of the header.
-- @return Function (which receives a filename as argument) that produces
--	the header and copies the content of the given file.
----------------------------------------------------------------------------
function buildplainhandler (type, subtype)
	return function (filename)
		contentheader (type, subtype)
		local fh = assert (_open (filename))
		local prog = fh:read("*a")
		fh:close()
		put (prog)
	end
end

----------------------------------------------------------------------------
-- Builds a handler that sends a header and the processed file.
-- Processes the file as a Lua Page.
-- @param type String with the type of the header.
-- @param subtype String with the subtype of the header.
-- @return Function (which receives a filename as argument) that produces
--	the header and processes the given file.
----------------------------------------------------------------------------
function buildprocesshandler (type, subtype)
	return function (filename)
		contentheader (type, subtype)
		lp.include (filename)
	end
end

----------------------------------------------------------------------------
-- Create an URL path to be used as a link to a CGILua script
-- @param script String with the name of the script.
-- @param args Table with arguments to script (optional).
-- @return String in URL format.
----------------------------------------------------------------------------
function mkurlpath (script, args)
	-- URL-encode the parameters to be passed do the script
	local params = ""
	if args then
		params = "?"..urlcode.encodetable(args)
	end
	if strsub(script,1,1) == "/" then
		return urlpath .. script .. params
	else
		return urlpath .. script_vdir .. script .. params
	end
end

----------------------------------------------------------------------------
-- Create an absolute URL containing the given URL path