Updated Whisper Push Notifications (markdown)

Whisper-Push-Notifications.md

@@ -280,19 +280,96 @@ var registerDevice = function (chatId, chatKey) {
 So, on `Device A` side, we have Chat Session Key, and we registered the device with that session. Now, we need to send/share the SymKey:
 
 ```js
+var shareChatKey = function (chatId, chatKey) {
+    console.log('chat session key: ', chatKey)
+    // pre-defined test identity (it gets injected automatically by statusd)
+    var deviceBIdentity = '0x04eedbaafd6adf4a9233a13e7b1c3c14461fffeba2e9054b8d456ce5f6ebeafadcbf3dce3716253fbc391277fa5a086b60b283daf61fb5b1f26895f456c2f31ae3';
+
+    // it is up to you how you share secret among participants, here is sample
+    var err = web3.shh.post({
+        from: identity,
+        to: deviceBIdentity,
+        topics: ["chatKeySharing"],
+        payload: '{"chat": "' + chatId + '", "key": "' + chatKey + '"}',
+        ttl: 20
+    });
+    if (err !== null) {
+        console.log("message NOT sent")
+    } else {
+        console.log("message sent OK")
+    }
+};
 ```
+You are free to use your own topic key, and format. What is important is the fact that Chat Session Key gets to the counter-party.
 
 On `Device B` side, we need to wait for shared key, and then, once we get it, register `Device B` with the chat session.
 
 ```js
-```
+var web3 = new Web3();
+web3.setProvider(new web3.providers.HttpProvider('http://localhost:8745'));
 
-Time to trigger notifications:
-```js
+// pre-defined test identity (it gets injected automatically by statusd)
+var identity = '0x04eedbaafd6adf4a9233a13e7b1c3c14461fffeba2e9054b8d456ce5f6ebeafadcbf3dce3716253fbc391277fa5a086b60b283daf61fb5b1f26895f456c2f31ae3';
+if (!web3.shh.hasIdentity(identity)) {
+    throw 'idenitity "0x04eedbaafd6adf4a9233a13e7b1c3c14461fffeba2e9054b8d456ce5f6ebeafadcbf3dce3716253fbc391277fa5a086b60b283daf61fb5b1f26895f456c2f31ae3" not found in whisper';
+}
+
+// for for key sharing, it is up to you how you implement it (which topic to use etc)
+var filter = web3.shh.filter({
+    to: identity, // wait for anon. messages to ourselves
+    topics: ['chatKeySharing']
+});
+filter.watch(function (error, result) {
+    if (!error) {
+        console.log("Chat key received: ", result);
+        // response will be in JSON, e.g. {chat: "0xdeadbeef", key: "0x04e68e37433baf55ddc2fe9f7533e4e722bcdad4239c98df92f3522907ced72d"}
+        var payload = JSON.parse(web3.toAscii(result.payload));
+        console.log(payload);
+
+        // no need to watch for the filter any more
+        filter.stopWatching();
+
+        // let's save incoming key
+        var keyname = payload.chat + '-chatkey';
+        web3.shh.deleteSymKey(keyname);
+        web3.shh.addSymKey(keyname, payload.key);
+
+        // now register ourselves
+        var deviceId = 'some-device-id'; // you obtain this from FCM
+        registerDevice(web3, identity, payload.chat, payload.key, deviceId);
+
+        // finally, trigger the notifications on all registered device (except for yourself)
+        // at this point it is really trivial, use the key + specific topic:
+        var err = web3.shh.post({
+            from: identity,
+            topics: [sendNotificationTopic],
+            payload: "Hello, you've got mail!!", // yes, arbitrary data!
+            ttl: 20,
+            keyname: keyname
+        });
+        if (err !== null) {
+            console.log("message NOT sent")
+        } else {
+            console.log("message sent OK")
+        }
+    }
+});
 ```
+We provide all the code for `Device B` in a single chunk. Basically, all that `Device B` does, is: wait for shared key, register device, trigger notification.
 
 # Implementation notes I: One-to-One Chats
 
 # Implementation notes II: Group Chats
 
 # Complete Sample
+
+Full sample page used for testing can be found here: https://gist.github.com/farazdagi/5ac082ddf006d00de422385f07d41ad3
+
+In order to use that page you need to start the following:
+```bash
+statusd --datadir app1 --http --httpport 8645 wnode # as Device A
+statusd --datadir app2 --http --httpport 8745 wnode # as Device B
+statusd --datadir wnode1 wnode --notify --password asdfasdf --injectaccounts=false # as notification server
+```
+
+# Limitations