Updated Whisper Push Notifications (markdown)

Whisper-Push-Notifications.md

@@ -232,6 +232,47 @@ Now, we have Chat Session Key, which we can use to register our device id (to be
 
 Let's see how `registerDevice()` might look like:
 ```js
+var newDeviceRegistrationTopic = '0x14621a51'; // NEW_DEVICE_REGISTRATION
+var ackDeviceRegistrationTopic = '0x424358d6'; // ACK_DEVICE_REGISTRATION
+var registerDevice = function (chatId, chatKey) {
+    console.log('chat session key: ', chatKey)
+    // this obtained from https://status-sandbox-c1b34.firebaseapp.com/
+    var deviceID = 'ca5pRJc6L8s:APA91bHpYFtpxvXx6uOayGmnNVnktA4PEEZdquCCt3fWR5ldLzSy1A37Tsbzk5Gavlmk1d_fvHRVnK7xPAhFFl-erF7O87DnIEstW6DEyhyiKZYA4dXFh6uy323f9A3uw5hEtT_kQVhT';
+
+    // make sure that chat key is loaded
+    var keyname = chatId + 'chatkey'; // there might be many chat keys
+    web3.shh.deleteSymKey(keyname);
+    web3.shh.addSymKey(keyname, chatKey);
+
+    // before sending request, let's start waiting for response
+    var filter = web3.shh.filter({
+        to: identity,
+        topics: [ackDeviceRegistrationTopic]
+    });
+    filter.watch(function (error, result) {
+        if (!error) {
+            console.log("Device Registration ACK received: ", result);
+            // response will be in JSON, e.g. {"server": "0xdeadbeef"}
+            var payload = JSON.parse(web3.toAscii(result.payload));
+
+            // no need to watch for the filter any more
+            filter.stopWatching();
+        }
+    });
+
+    var err = web3.shh.post({
+        from: identity,
+        topics: [newDeviceRegistrationTopic],
+        payload: '{"device": "' + deviceID + '"}',
+        ttl: 20,
+        keyname: keyname
+    });
+    if (err !== null) {
+        console.log("message NOT sent")
+    } else {
+        console.log("message sent OK")
+    }
+};
 ```
 
 ### 3. Sharing Chat session key, and allowing notifications