feat: login with Google

Allow users to login with Google
Display name of user along with their message in chat room

Author: kingisaac95

.env-sample

@@ -0,0 +1,4 @@
+GOOGLE_CLIENT_ID=
+GOOGLE_CLIENT_SECRET=
+GOOGLE_REDIRECT_URL="http://localhost:8080/auth/callback/google"
+SECURITY_KEY=<Any key of your choosing>

.gitignore

@@ -1,2 +1,3 @@
 # Ignore build for now
-build
+build
+.env

README.md

@@ -9,6 +9,14 @@ they choose. These are done via different threads(goroutines).
 
 This is still largely a WIP, but I'll keep updating it till I'm done
 
+## Enviroment Variables
+
+```
+touch .env; cp .env-sample .env
+```
+
+Visit Google Cloud Console, navigate to API & Services and click on the Credentials section to get the API key and secret.
+
 ## Meta
 
 Orjiewuru Kingdom – [@kingisaac95](https://twitter.com/kingisaac95), [email protected]

auth/auth.go

@@ -2,9 +2,11 @@ package auth
 
 import (
 	"fmt"
-	"log"
 	"net/http"
 	"strings"
+
+	"github.com/stretchr/gomniauth"
+	"github.com/stretchr/objx"
 )
 
 type authHandler struct {
@@ -37,11 +39,6 @@ func Required(handler http.Handler) http.Handler {
 
 // LoginHandler handles third-party login process
 func LoginHandler(w http.ResponseWriter, r *http.Request) {
-	const (
-		LOGIN    string = "login"
-		CALLBACK string = "callback"
-	)
-
 	segs := strings.Split(r.URL.Path, "/")
 
 	if len(segs) < 4 {
@@ -51,9 +48,49 @@ func LoginHandler(w http.ResponseWriter, r *http.Request) {
 
 	action := segs[2]
 	provider := segs[3]
+
 	switch action {
-	case LOGIN:
-		log.Println("TODO: handle login for", provider)
+	case "login":
+		provider, err := gomniauth.Provider(provider)
+		if err != nil {
+			http.Error(w, fmt.Sprintf("Error when trying to get provider %s: %s", provider, err), http.StatusBadRequest)
+			return
+		}
+
+		loginURL, err := provider.GetBeginAuthURL(nil, nil)
+		if err != nil {
+			http.Error(w, fmt.Sprintf("Error when trying to GetBeginAuthURL for %s:%s", provider, err), http.StatusInternalServerError)
+			return
+		}
+
+		w.Header().Set("Location", loginURL)
+		w.WriteHeader(http.StatusTemporaryRedirect)
+	case "callback":
+		provider, err := gomniauth.Provider(provider)
+		if err != nil {
+			http.Error(w, fmt.Sprintf("Error when trying to get provider %s: %s", provider, err), http.StatusBadRequest)
+			return
+		}
+		creds, err := provider.CompleteAuth(objx.MustFromURLQuery(r.URL.RawQuery))
+		if err != nil {
+			http.Error(w, fmt.Sprintf("Error when trying to complete auth for %s: %s", provider, err), http.StatusInternalServerError)
+			return
+		}
+		user, err := provider.GetUser(creds)
+		if err != nil {
+			http.Error(w, fmt.Sprintf("Error when trying to get user from %s: %s", provider, err), http.StatusInternalServerError)
+			return
+		}
+		authCookieValue := objx.New(map[string]interface{}{
+			"name": user.Name(),
+		}).MustBase64()
+		http.SetCookie(w, &http.Cookie{
+			Name:  "auth",
+			Value: authCookieValue,
+			Path:  "/",
+		})
+		w.Header().Set("Location", "/chat")
+		w.WriteHeader(http.StatusTemporaryRedirect)
 	default:
 		w.WriteHeader(http.StatusNotFound)
 		fmt.Fprintf(w, "Auth action %s not supported", action)

chat/client.go

@@ -1,6 +1,8 @@
 package chat
 
 import (
+	"time"
+
 	"github.com/gorilla/websocket"
 )
 
@@ -9,26 +11,31 @@ type client struct {
 	// socket: the web socket for this client
 	socket *websocket.Conn
 	// send: channel on which the messages are sent
-	send chan []byte
+	send chan *message
 	// room: the room this client is chatting in
 	room *room
+	// userData holds information about the user
+	userData map[string]interface{}
 }
 
 func (c *client) read() {
 	defer c.socket.Close()
 	for {
-		_, msg, err := c.socket.ReadMessage()
+		var msg *message
+		err := c.socket.ReadJSON(&msg)
 		if err != nil {
 			return
 		}
+		msg.When = time.Now()
+		msg.Name = c.userData["name"].(string)
 		c.room.forward <- msg
 	}
 }
 
 func (c *client) write() {
 	defer c.socket.Close()
 	for msg := range c.send {
-		err := c.socket.WriteMessage(websocket.TextMessage, msg)
+		err := c.socket.WriteJSON(msg)
 		if err != nil {
 			return
 		}

chat/message.go

@@ -0,0 +1,9 @@
+package chat
+
+import "time"
+
+type message struct {
+	Name    string
+	Message string
+	When    time.Time
+}

chat/room.go

@@ -2,15 +2,17 @@ package chat
 
 import (
 	"chat_app/trace"
-	"github.com/gorilla/websocket"
 	"log"
 	"net/http"
+
+	"github.com/gorilla/websocket"
+	"github.com/stretchr/objx"
 )
 
 type room struct {
 	// forward: a channel that holds incoming messages
 	// that should be forwarded to the other clients.
-	forward chan []byte
+	forward chan *message
 	// join: a channel for clients wishing to join the room
 	join chan *client
 	// leave: a channel for clients wishing to leave the room
@@ -24,7 +26,7 @@ type room struct {
 // NewRoom helper for creating rooms
 func NewRoom() *room {
 	return &room{
-		forward: make(chan []byte),
+		forward: make(chan *message),
 		join:    make(chan *client),
 		leave:   make(chan *client),
 		clients: make(map[*client]bool),
@@ -45,7 +47,7 @@ func (r *room) Run() {
 			close(client.send)
 			r.Tracer.Trace("Client left.")
 		case msg := <-r.forward:
-			r.Tracer.Trace("Message received: ", string(msg))
+			r.Tracer.Trace("Message received: ", msg.Message)
 			for client := range r.clients {
 				client.send <- msg
 				r.Tracer.Trace(" -- sent to client.")
@@ -73,11 +75,18 @@ func (r *room) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 		log.Fatal("ServeHTTP:", err)
 		return
 	}
+
+	authCookie, err := req.Cookie("auth")
+	if err != nil {
+		log.Fatal("Failed to get auth cookie:", err)
+		return
+	}
 	// create a client from the socket
 	client := &client{
-		socket: socket,
-		send:   make(chan []byte, messageBufferSize),
-		room:   r,
+		socket:   socket,
+		send:     make(chan *message, messageBufferSize),
+		room:     r,
+		userData: objx.MustFromBase64(authCookie.Value),
 	}
 	// add the client to the current room
 	r.join <- client

go.mod

@@ -2,4 +2,16 @@ module chat_app
 
 go 1.13
 
-require github.com/gorilla/websocket v1.4.1
+require (
+	github.com/clbanning/x2j v0.0.0-20191024224557-825249438eec // indirect
+	github.com/gorilla/websocket v1.4.1
+	github.com/joho/godotenv v1.3.0
+	github.com/stretchr/codecs v0.0.0-20170403063245-04a5b1e1910d // indirect
+	github.com/stretchr/gomniauth v0.0.0-20170717123514-4b6c822be2eb
+	github.com/stretchr/objx v0.2.0
+	github.com/stretchr/signature v0.0.0-20160104132143-168b2a1e1b56 // indirect
+	github.com/stretchr/stew v0.0.0-20130812190256-80ef0842b48b // indirect
+	github.com/stretchr/tracer v0.0.0-20140124184152-66d3696bba97 // indirect
+	github.com/ugorji/go v1.1.7 // indirect
+	gopkg.in/mgo.v2 v2.0.0-20190816093944-a6b53ec6cb22 // indirect
+)

go.sum

@@ -1,2 +1,29 @@
+github.com/clbanning/x2j v0.0.0-20191024224557-825249438eec h1:EdRZT3IeKQmfCSrgo8SZ8V3MEnskuJP0wCYNpe+aiXo=
+github.com/clbanning/x2j v0.0.0-20191024224557-825249438eec/go.mod h1:jMjuTZXRI4dUb/I5gc9Hdhagfvm9+RyrPryS/auMzxE=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/gorilla/websocket v1.4.1 h1:q7AeDBpnBk8AogcD4DSag/Ukw/KV+YhzLj2bP5HvKCM=
 github.com/gorilla/websocket v1.4.1/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
+github.com/joho/godotenv v1.3.0 h1:Zjp+RcGpHhGlrMbJzXTrZZPrWj+1vfm90La1wgB6Bhc=
+github.com/joho/godotenv v1.3.0/go.mod h1:7hK45KPybAkOC6peb+G5yklZfMxEjkZhHbwpqxOKXbg=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/codecs v0.0.0-20170403063245-04a5b1e1910d h1:gXQ+QS3q874pcayiqszimfHPQ7ySFcekgzBMoTaVawk=
+github.com/stretchr/codecs v0.0.0-20170403063245-04a5b1e1910d/go.mod h1:RpfDhdqip2BYhzoE4esKm8axH5VywpvMW9o3wfcamek=
+github.com/stretchr/gomniauth v0.0.0-20170717123514-4b6c822be2eb h1:6lYIg/SCrz3gsCsEpRpK0BW3tBGt4VuQKlAleoxCgCc=
+github.com/stretchr/gomniauth v0.0.0-20170717123514-4b6c822be2eb/go.mod h1:5wVraTCYvqbNMRjmSIIcrJMASXdoHeXm8j8AON7WobA=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.2.0 h1:Hbg2NidpLE8veEBkEZTL3CvlkUIVzuU9jDplZO54c48=
+github.com/stretchr/objx v0.2.0/go.mod h1:qt09Ya8vawLte6SNmTgCsAVtYtaKzEcn8ATUoHMkEqE=
+github.com/stretchr/signature v0.0.0-20160104132143-168b2a1e1b56 h1:BTR9AeovoABP8KnaBkzNtp7y/+x1n5GbOHwp3QisE1k=
+github.com/stretchr/signature v0.0.0-20160104132143-168b2a1e1b56/go.mod h1:p8v7xBdwApv7pgPN+8jQ3LpBQJDAusrtE+YBWBbab9Q=
+github.com/stretchr/stew v0.0.0-20130812190256-80ef0842b48b h1:DmfFjW6pLdaJNVHfKgCxTdKFI6tM+0YbMd0kx7kE78s=
+github.com/stretchr/stew v0.0.0-20130812190256-80ef0842b48b/go.mod h1:yS/5aMz+lfJhykLjlAGbnhUhZIvVapOvtmk0MtzHktE=
+github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+github.com/stretchr/tracer v0.0.0-20140124184152-66d3696bba97 h1:ZXZ3Ko4supnaInt/pSZnq3QL65Qx/KSZTUPMJH5RlIk=
+github.com/stretchr/tracer v0.0.0-20140124184152-66d3696bba97/go.mod h1:H0mYc1JTiYc9K0keLMYcR2ybyeom20X4cOYrKya1M1Y=
+github.com/ugorji/go v1.1.7 h1:/68gy2h+1mWMrwZFeD1kQialdSzAb432dtpeJ42ovdo=
+github.com/ugorji/go v1.1.7/go.mod h1:kZn38zHttfInRq0xu/PH0az30d+z6vm202qpg1oXVMw=
+github.com/ugorji/go/codec v1.1.7 h1:2SvQaVZ1ouYrrKKwoSk2pzd4A9evlKJb9oTL+OaLUSs=
+github.com/ugorji/go/codec v1.1.7/go.mod h1:Ax+UKWsSmolVDwsd+7N3ZtXu+yMGCf907BLYF3GoBXY=
+gopkg.in/mgo.v2 v2.0.0-20190816093944-a6b53ec6cb22 h1:VpOs+IwYnYBaFnrNAeB8UUWtL3vEUnzSCL1nVjPhqrw=
+gopkg.in/mgo.v2 v2.0.0-20190816093944-a6b53ec6cb22/go.mod h1:yeKp02qBN3iKW1OzL3MGk2IdtZzaj7SFntXj72NppTA=

main.go

@@ -6,9 +6,15 @@ import (
 	"flag"
 	"log"
 	"net/http"
+	"os"
 	"path/filepath"
 	"sync"
 	"text/template"
+
+	"github.com/joho/godotenv"
+	"github.com/stretchr/gomniauth"
+	"github.com/stretchr/gomniauth/providers/google"
+	"github.com/stretchr/objx"
 )
 
 // templ is a single template
@@ -22,13 +28,32 @@ func (t *templateHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	t.once.Do(func() {
 		t.templ = template.Must(template.ParseFiles(filepath.Join("templates", t.filename)))
 	})
-	t.templ.Execute(w, r)
+	data := map[string]interface{}{
+		"Host": r.Host,
+	}
+	if authCookie, err := r.Cookie("auth"); err == nil {
+		data["UserData"] = objx.MustFromBase64(authCookie.Value)
+	}
+	t.templ.Execute(w, data)
 }
 
 func main() {
 	var port = flag.String("port", ":8080", "The port where our application runs.")
 	flag.Parse() // parse flags and extract appropriate information
 
+	err := godotenv.Load()
+	if err != nil {
+		log.Fatal("Error loading .env file")
+	}
+
+	googleClientID := os.Getenv("GOOGLE_CLIENT_ID")
+	googleClientSecret := os.Getenv("GOOGLE_CLIENT_SECRET")
+	googleRedirectURL := os.Getenv("GOOGLE_REDIRECT_URL")
+	securityKey := os.Getenv("SECURITY_KEY")
+
+	gomniauth.SetSecurityKey(securityKey)
+	gomniauth.WithProviders(google.New(googleClientID, googleClientSecret, googleRedirectURL))
+
 	// new room setup
 	r := chat.NewRoom()