Lua for Lighttpd to rewrite to a handler script if cached copy of requested file is missing

gistfile1.lua

cache_path = "/var/www/site/tmp"
cache_code = "compile"

-- render and cache to the filesystem
function cache_gen()
	lighty.env["physical.path"]  = lighty.env["physical.doc-root"] .. "/index.php"
	lighty.env["uri.query"] = "p=" .. string.gsub(lighty.env["uri.path"], "\.(htm|html)$", "") 
	--print ("CACHE: " .. lighty.env["uri.query"])
end

-- load the cached copy from the filesystem
function cache_load() 
	lighty.env["physical.path"] = cache_path .. lighty.env["uri.path"]
	--print ("LOAD: " .. cache_path .. lighty.env["uri.path"])
end

-- add index file if directory listing requested
if(lighty.env["uri.path"] == "" or string.find(lighty.env["uri.path"], "/", -1)) then
	lighty.env["uri.path"] = lighty.env["uri.path"] .. "index.html"
end

-- process htm|html file requests
if(string.find(lighty.env["uri.path"], "htm", -4)) then 
	exists = lighty.stat(cache_path .. lighty.env["uri.path"])
	
	cache_code_passed = false
	if(lighty.env["uri.query"] ) then
		cache_code_passed = string.find(lighty.env["uri.query"], cache_code)
	end
	
	if(exists and not cache_code_passed) then
		action = cache_load()
	else
		action = cache_gen()
	end
end