Example #1
0
func (lua *LuaExt) exec(reqLogger log.Logger, app *LuaApp, appID, reqId, script string, w http.ResponseWriter, r *http.Request) int {
	// FIXME(tsileo) a debug mode, with a defer/recover
	// also parse the Lu error and show the bugging line!
	start := time.Now()
	httpClient := &http.Client{}
	// Initialize internal Lua module written in Go
	logger := loggerModule.New(reqLogger.New("ctx", "Lua"), start, reqId)
	response := responseModule.New()
	request := requestModule.New(r, reqId, lua.authFunc)
	blobstore := blobstoreModule.New(lua.blobStore)
	kvstore := kvstoreModule.New(lua.kvStore)
	bewit := bewitModule.New(reqLogger.New("ctx", "Lua bewit module"), r)
	template := templateModule.New()

	// Initialize Lua state
	L := luamod.NewState()
	defer L.Close()
	setCustomGlobals(L)
	L.PreloadModule("request", request.Loader)
	L.PreloadModule("response", response.Loader)
	L.PreloadModule("logger", logger.Loader)
	L.PreloadModule("blobstore", blobstore.Loader)
	L.PreloadModule("kvstore", kvstore.Loader)
	L.PreloadModule("bewit", bewit.Loader)
	L.PreloadModule("template", template.Loader)
	// TODO(tsileo) docstore module
	// TODO(tsileo) cookies module
	// TODO(tsileo) lru module
	// TODO(tsileo) cache module => to cache response
	// TODO(tsileo) load module from github directly?
	// TODO(tsileo) ETag support

	// 3rd party module
	luajson.Preload(L)
	L.PreloadModule("http", gluahttp.NewHttpModule(httpClient).Loader)

	// Set some global variables
	L.SetGlobal("reqID", luamod.LString(reqId))
	L.SetGlobal("appID", luamod.LString(appID))

	// Execute the code
	if err := L.DoString(script); err != nil {
		// FIXME better error, with debug mode?
		panic(err)
	}

	// Apply the Response object to the actual response
	response.WriteTo(w)
	// TODO save the logRecords in the AppStats and find a way to serve them over Server-Sent Events
	// keep them in memory with the ability to dump them in bulk as blob for later query
	// logRecords := logger.Records()
	for _, logRecord := range logger.Records() {
		app.logs = append(app.logs, logRecord)
	}

	reqLogger.Info("Script executed", "response", response, "duration", time.Since(start))
	return response.Status()
}
Example #2
0
func setCustomGlobals(L *luamod.LState) {
	// Return the server unix timestamp
	L.SetGlobal("unix", L.NewFunction(func(L *luamod.LState) int {
		L.Push(luamod.LNumber(time.Now().Unix()))
		return 1
	}))

	// Generate a random hexadecimal ID with the current timestamp as first 4 bytes,
	// this means keys will be sorted by creation date automatically if sorted lexicographically
	L.SetGlobal("hexid", L.NewFunction(func(L *luamod.LState) int {
		id, err := hexid.New(int(time.Now().UTC().Unix()))
		if err != nil {
			panic(err)
		}
		L.Push(luamod.LString(id.String()))
		return 1
	}))

	// Compute the Blake2B hash for the given string
	L.SetGlobal("blake2b", L.NewFunction(func(L *luamod.LState) int {
		hash := fmt.Sprintf("%x", blake2b.Sum256([]byte(L.ToString(1))))
		L.Push(luamod.LString(hash))
		return 1
	}))

	// Sleep for the given number of seconds
	L.SetGlobal("sleep", L.NewFunction(func(L *luamod.LState) int {
		time.Sleep(time.Duration(float64(L.ToNumber(1)) * float64(1e9)))
		return 0
	}))

	// Convert the given Markdown to HTML
	L.SetGlobal("markdownify", L.NewFunction(func(L *luamod.LState) int {
		output := blackfriday.MarkdownCommon([]byte(L.ToString(1)))
		L.Push(luamod.LString(string(output)))
		return 1
	}))

	// Render execute a Go HTML template, data must be a table with string keys
	L.SetGlobal("render", L.NewFunction(func(L *luamod.LState) int {
		tplString := L.ToString(1)
		data := luautil.TableToMap(L.ToTable(2))
		tpl, err := template.New("tpl").Parse(tplString)
		if err != nil {
			L.Push(luamod.LString(err.Error()))
			return 1
		}
		// TODO(tsileo) add some templatFuncs/template filter
		out := &bytes.Buffer{}
		if err := tpl.Execute(out, data); err != nil {
			L.Push(luamod.LString(err.Error()))
			return 1
		}
		L.Push(luamod.LString(out.String()))
		return 1
	}))

	// TODO(tsileo) a urljoin?

	// Return an absoulte URL for the given path
	L.SetGlobal("url", L.NewFunction(func(L *luamod.LState) int {
		// FIXME(tsileo) take the host from the req?
		L.Push(luamod.LString("http://localhost:8050" + L.ToString(1)))
		return 1
	}))
}