Initial prototype

main.go

@@ -0,0 +1,192 @@
+package main
+
+import (
+	"bytes"
+	"excalidraw-backend/core"
+	"excalidraw-backend/documents/memory"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/go-chi/chi/v5"
+	"github.com/go-chi/chi/v5/middleware"
+	"github.com/go-chi/cors"
+	"github.com/go-chi/render"
+	"github.com/oklog/ulid/v2"
+	"github.com/zishang520/engine.io/v2/types"
+	socketio "github.com/zishang520/socket.io/v2/socket"
+)
+
+type (
+	DocumentCreateResponse struct {
+		ID string `json:"id"`
+	}
+
+	UserToFollow struct {
+		SocketId string
+		Username string
+	}
+	OnUserFollowedPayload struct {
+		UserToFollow UserToFollow
+		action       string
+	}
+)
+
+func main() {
+	opts := socketio.DefaultServerOptions()
+	opts.SetMaxHttpBufferSize(5000000)
+	opts.SetPath("/socket.io")
+	opts.SetAllowEIO3(true)
+	opts.SetCors(&types.Cors{
+		Origin:      "*",
+		Credentials: true,
+	})
+	ioo := socketio.NewServer(nil, opts)
+	ioo.On("connection", func(clients ...any) {
+		socket := clients[0].(*socketio.Socket)
+		ioo.To(socketio.Room(socket.Id())).Emit("init-room")
+		me := socket.Id()
+		socket.On("join-room", func(datas ...any) {
+			room := socketio.Room(datas[0].(string))
+			fmt.Printf("Socket %v has joined %v\n", me, room)
+			socket.Join(room)
+			ioo.In(room).FetchSockets()(func(sockets []*socketio.RemoteSocket, _ error) {
+
+				if len(sockets) <= 1 {
+					ioo.To(socketio.Room(socket.Id())).Emit("first-in-room")
+				} else {
+					fmt.Printf("emit new user %v in room %v\n", me, room)
+					socket.Broadcast().To(room).Emit("new-user", me)
+				}
+
+				data := []socketio.SocketId{}
+				for _, osocket := range sockets {
+					data = append(data, osocket.Id())
+				}
+				fmt.Printf(" room %v has users %v\n", room, data)
+
+				ioo.In(room).Emit(
+					"room-user-change",
+					data,
+				)
+
+			})
+		})
+		socket.On("server-broadcast", func(datas ...any) {
+			roomID := datas[0].(string)
+			fmt.Printf(" user %v sends update to room %v\n", me, roomID)
+			socket.Broadcast().To(socketio.Room(roomID)).Emit("client-broadcast", datas[1], datas[2])
+		})
+		socket.On("server-volatile-broadcast", func(datas ...any) {
+			roomID := datas[0].(string)
+			fmt.Printf(" user %v sends volatile update to room %v\n", me, roomID)
+			socket.Volatile().Broadcast().To(socketio.Room(roomID)).Emit("client-broadcast", datas[1], datas[2])
+		})
+
+		socket.On("user-follow", func(datas ...any) {
+			// TODO()
+
+		})
+		socket.On("disconnecting", func(datas ...any) {
+			for _, oroom := range socket.Rooms().Keys() {
+				ioo.In(oroom).FetchSockets()(func(sockets []*socketio.RemoteSocket, _ error) {
+					otherClients := []socketio.SocketId{}
+					fmt.Printf("disconnecting %v from room %v", me, oroom)
+					for _, osocket := range sockets {
+						if osocket.Id() != me {
+							otherClients = append(otherClients, osocket.Id())
+							fmt.Println("other", osocket.Id())
+						}
+					}
+					if len(otherClients) > 0 {
+						ioo.In(oroom).Emit(
+							"room-user-change",
+							otherClients,
+						)
+
+					}
+
+				})
+
+			}
+
+		})
+		socket.On("disconnect", func(datas ...any) {
+			socket.RemoveAllListeners("")
+			socket.Disconnect(true)
+		})
+	})
+
+	r := chi.NewRouter()
+	r.Use(middleware.Logger)
+
+	r.Use(cors.Handler(cors.Options{
+		AllowedOrigins:   []string{"https://*", "http://*"},
+		AllowedMethods:   []string{"GET", "POST", "PUT", "DELETE", "OPTIONS"},
+		AllowedHeaders:   []string{"Accept", "Authorization", "Content-Type", "Content-Length", "X-CSRF-Token", "Token", "session", "Origin", "Host", "Connection", "Accept-Encoding", "Accept-Language", "X-Requested-With"},
+		AllowCredentials: true,
+		MaxAge:           300, // Maximum value not ignored by any of major browsers
+	}))
+
+	documentStore := memory.NewDocumentStore()
+
+	r.Get("/", func(w http.ResponseWriter, r *http.Request) {
+		w.Write([]byte("you are all set"))
+		fmt.Println(ulid.Make())
+		render.Status(r, http.StatusOK)
+	})
+
+	r.Route("/api/v2", func(r chi.Router) {
+		r.Post("/post/", func(w http.ResponseWriter, r *http.Request) {
+			data := new(bytes.Buffer)
+			_, err := io.Copy(data, r.Body)
+			if err != nil {
+				http.Error(w, "Failed to copy", http.StatusInternalServerError)
+				return
+			}
+			id, err := documentStore.Create(r.Context(), &core.Document{Data: *data})
+			if err != nil {
+				http.Error(w, "Failed to save", http.StatusInternalServerError)
+				return
+			}
+
+			render.JSON(w, r, DocumentCreateResponse{ID: id})
+			render.Status(r, http.StatusOK)
+		})
+		r.Route("/{id}", func(r chi.Router) {
+			r.Get("/", func(w http.ResponseWriter, r *http.Request) {
+				id := chi.URLParam(r, "id")
+				document, err := documentStore.FindID(r.Context(), id)
+				if err != nil {
+					http.Error(w, "not found", http.StatusNotFound)
+					return
+				}
+				w.Write(document.Data.Bytes())
+			})
+		})
+	})
+
+	r.Handle("/socket.io/", ioo.ServeHandler(nil))
+	go http.ListenAndServe(":3002", r)
+
+	exit := make(chan struct{})
+	SignalC := make(chan os.Signal)
+
+	signal.Notify(SignalC, os.Interrupt, syscall.SIGHUP, syscall.SIGINT, syscall.SIGTERM, syscall.SIGQUIT)
+	go func() {
+		for s := range SignalC {
+			switch s {
+			case os.Interrupt, syscall.SIGHUP, syscall.SIGINT, syscall.SIGTERM, syscall.SIGQUIT:
+				close(exit)
+				return
+			}
+		}
+	}()
+
+	<-exit
+	ioo.Close(nil)
+	os.Exit(0)
+}