bundlua: CSS/JavaScript bundler for lighttpd mod_magnet (from 2007)

bundlua.lua

-- bundlua: a css/javascript bundler written in LUA for lighttpd's mod_magnet
-- Paul Annesley : paul@annesley.cc : 2007-02-12
-- URL format: /bundle/file1.css,file2.css

-- include trailing slash for directories
local urlPrefix = '/bundle/'
local basedir = '/path/to/htdocs/'
local cssDir = basedir .. 'css/'
local jsDir = basedir .. 'js/'
local cacheDir = '/path/to/cache/dir/'

local requestPath = lighty.env['uri.path']
if (string.find(requestPath, urlPrefix, 1, true) == 1) then

	local cacheHit = false
	local fileString = string.sub(requestPath, string.len(urlPrefix)+1)

	-- determine content type
	if (string.sub(fileString, -4) == '.css') then
		srcDir = cssDir
	elseif (string.sub(fileString, -3) == '.js') then
		srcDir = jsDir
	else
		return 404
	end

	-- get list of existing files and most recent mtime
	local requestFilenames = {}
	local lastMod = 0
	for name in string.gmatch(fileString, '%w[%w%-%_]*%.%w%w%w?') do
		local fileStat = lighty.stat(srcDir .. name)
		if (fileStat) then
			local mtime = fileStat.st_mtime
			if (mtime > lastMod) then lastMod = mtime end
			table.insert(requestFilenames, name)
		end
	end

	-- 404 if no files
	if (# requestFilenames == 0) then return 404 end

	-- check for a cache hit
	local bundleFile = cacheDir .. lastMod .. '-' .. fileString
	local bundleStat = lighty.stat(bundleFile)
	if (bundleStat and lastMod <= bundleStat.st_mtime) then cacheHit = true end

	if (cacheHit == false) then
		-- bundle files
		local outHandle = io.open(bundleFile, 'w+')
		if (outHandle) then
			outHandle:write("/* bundlua @ " .. os.date('%Y-%m-%d %T') .. " */\n\n")
			for i,name in ipairs(requestFilenames) do
				local path = srcDir .. name
				local inHandle = io.open(path)
				if (inHandle) then
					outHandle:write("/* --- " .. name .. " --- */\n")
					outHandle:write(inHandle:read('*a') .. "\n")
					io.close(inHandle)
				else
					print('Unable to open ' .. path .. ' for reading')
				end
			end
			outHandle:flush()
			io.close(outHandle)
		else
			print('Unable to open ' .. bundleFile .. ' for writing')
		end
	end

	-- tell lighttpd where it's at
	lighty.env["physical.path"] = bundleFile
	lighty.env["physical.doc-root"] = cacheDir
	lighty.env["physical.rel-path"] = '/' .. fileString
	lighty.header['X-Bundlua-Cache-Hit'] = tostring(cacheHit)

end