implemented auth utilities for yjs

src/Connector.js

@@ -1,6 +1,9 @@
 /* @flow */
 'use strict'
 
+function canRead (auth) { return auth === 'read' || auth === 'write' }
+function canWrite (auth) { return auth === 'write' }
+
 module.exports = function (Y/* :any */) {
   class AbstractConnector {
     /* ::
@@ -54,6 +57,8 @@ module.exports = function (Y/* :any */) {
       this.syncStep2 = Promise.resolve()
       this.broadcastOpBuffer = []
       this.protocolVersion = 11
+      this.authInfo = opts.auth || null
+      this.checkAuth = opts.checkAuth || function () { return Promise.resolve('write') } // default is everyone has write access
     }
     reconnect () {
     }
@@ -87,6 +92,9 @@ module.exports = function (Y/* :any */) {
     onUserEvent (f) {
       this.userEventListeners.push(f)
     }
+    removeUserEventListener (f) {
+      this.userEventListeners = this.userEventListeners.filter(g => { f !== g })
+    }
     userLeft (user) {
       if (this.connections[user] != null) {
         delete this.connections[user]
@@ -163,7 +171,8 @@ module.exports = function (Y/* :any */) {
             type: 'sync step 1',
             stateSet: stateSet,
             deleteSet: deleteSet,
-            protocolVersion: conn.protocolVersion
+            protocolVersion: conn.protocolVersion,
+            auth: conn.authInfo
           })
         })
       } else {
@@ -217,7 +226,7 @@ module.exports = function (Y/* :any */) {
     */
     receiveMessage (sender/* :UserId */, message/* :Message */) {
       if (sender === this.userId) {
-        return
+        return Promise.resolve()
       }
       if (this.debug) {
         console.log(`receive ${sender} -> ${this.userId}: ${message.type}`, JSON.parse(JSON.stringify(message))) // eslint-disable-line
@@ -232,14 +241,36 @@ module.exports = function (Y/* :any */) {
           type: 'sync stop',
           protocolVersion: this.protocolVersion
         })
-        return
+        return Promise.reject('Incompatible protocol version')
       }
-      if (message.type === 'sync step 1') {
+      if (message.auth != null && this.connections[sender] != null) {
+        // authenticate using auth in message
+        var auth = this.checkAuth(message.auth, this.y)
+        this.connections[sender].auth = auth
+        auth.then(auth => {
+          for (var f of this.userEventListeners) {
+            f({
+              action: 'userAuthenticated',
+              user: sender,
+              auth: auth
+            })
+          }
+        })
+      } else if (this.connections[sender] != null && this.connections[sender].auth == null) {
+        // authenticate without otherwise
+        this.connections[sender].auth = this.checkAuth(null, this.y)
+      }
+      if (this.connections[sender] != null && this.connections[sender].auth != null) {
+        return this.connections[sender].auth.then((auth) => {
+          if (message.type === 'sync step 1' && canRead(auth)) {
             let conn = this
             let m = message
+
             this.y.db.requestTransaction(function *() {
               var currentStateSet = yield* this.getStateSet()
+              if (canWrite(auth)) {
                 yield* this.applyDeleteSet(m.deleteSet)
+              }
 
               var ds = yield* this.getDeleteSet()
               var ops = yield* this.getOperations(m.stateSet)
@@ -248,7 +279,8 @@ module.exports = function (Y/* :any */) {
                 os: ops,
                 stateSet: currentStateSet,
                 deleteSet: ds,
-            protocolVersion: this.protocolVersion
+                protocolVersion: this.protocolVersion,
+                auth: this.authInfo
               })
               if (this.forwardToSyncingClients) {
                 conn.syncingClients.push(sender)
@@ -267,7 +299,7 @@ module.exports = function (Y/* :any */) {
               }
               conn._setSyncedWith(sender)
             })
-      } else if (message.type === 'sync step 2') {
+          } else if (message.type === 'sync step 2' && canWrite(auth)) {
             let conn = this
             var broadcastHB = !this.broadcastedHB
             this.broadcastedHB = true
@@ -302,7 +334,7 @@ module.exports = function (Y/* :any */) {
             this.syncStep2.then(function () {
               self._setSyncedWith(sender)
             })
-      } else if (message.type === 'update') {
+          } else if (message.type === 'update' && canWrite(auth)) {
             if (this.forwardToSyncingClients) {
               for (var client of this.syncingClients) {
                 this.send(client, message)
@@ -318,6 +350,10 @@ module.exports = function (Y/* :any */) {
             }
             this.y.db.apply(message.ops)
           }
+        })
+      } else {
+        return Promise.reject('Unable to deliver message')
+      }
     }
     _setSyncedWith (user) {
       var conn = this.connections[user]

src/Connectors/Test.js

@@ -24,11 +24,21 @@ module.exports = function (Y) {
       }
     },
     whenTransactionsFinished: function () {
+      var self = this
+      return new Promise (function (resolve, reject) {
+        // The connector first has to send the messages to the db.
+        // Wait for the checkAuth-function to resolve
+        // The test lib only has a simple checkAuth function: `() => Promise.resolve()`
+        // Just add a function to the event-queue, in order to wait for the event.
+        // TODO: this may be buggy in test applications (but it isn't be for real-life apps)
+        setTimeout(function () {
           var ps = []
-      for (var name in this.users) {
+          for (var name in self.users) {
-        ps.push(this.users[name].y.db.whenTransactionsFinished())
+            ps.push(self.users[name].y.db.whenTransactionsFinished())
           }
-      return Promise.all(ps)
+          Promise.all(ps).then(resolve, reject)
+        }, 0)
+      })
     },
     flushOne: function flushOne () {
       var bufs = []
@@ -54,8 +64,9 @@ module.exports = function (Y) {
           delete buff[sender]
         }
         var user = globalRoom.users[userId]
-        user.receiveMessage(m[0], m[1])
+        return user.receiveMessage(m[0], m[1]).then(function () {
           return user.y.db.whenTransactionsFinished() 
+        }, function () {})
       } else {
         return false
       }
@@ -72,7 +83,6 @@ module.exports = function (Y) {
             }
             globalRoom.whenTransactionsFinished().then(nextFlush)
           } else {
-            setTimeout(function () {
             var c = globalRoom.flushOne()
             if (c) {
               c.then(function () {
@@ -81,7 +91,6 @@ module.exports = function (Y) {
             } else {
               resolve()
             }
-            }, 0)
           }
         }
         globalRoom.whenTransactionsFinished().then(nextFlush)
@@ -107,7 +116,7 @@ module.exports = function (Y) {
       this.syncingClientDuration = 0
     }
     receiveMessage (sender, m) {
-      super.receiveMessage(sender, JSON.parse(JSON.stringify(m)))
+      return super.receiveMessage(sender, JSON.parse(JSON.stringify(m)))
     }
     send (userId, message) {
       var buffer = globalRoom.buffers[userId]
@@ -154,7 +163,7 @@ module.exports = function (Y) {
           if (buff[sender].length === 0) {
             delete buff[sender]
           }
-          this.receiveMessage(m[0], m[1])
+          yield this.receiveMessage(m[0], m[1])
         }
         yield self.whenTransactionsFinished()
       })