PubNub as webhook transmitter to avoid firewall issues. Description i…

…n example4.md and working template in templates folder

docs/example4.md

@@ -0,0 +1,105 @@
+## Example #4 Using PubNub
+An inbound, internet reachable port, is required for the Webex Teams API to notify
+Flint of webhook events. This is not always easy or possible.
+
+The standard way to handle firewall tunneling is via a tool like ngrok or a web server in the DMZ.
+Here we use a different approach. We are using a PubNub server as a way to transmit the webhook event to
+the flint application, which uses a PubNub client to receive the event. PubNub uses whatever mechanism is best suited to reach the PubHub nodes.
+
+There is a PubNub function you need to deploy at PubNub. It's in the file pubnub-function.js.
+Check their tutorial here:
+https://www.pubnub.com/tutorials/pubnub-functions/
+Configure the function to run 'On Request'
+
+Once you configured your PubNub function (block) you should copy the URL and configure it as WebhookRecipientURL 
+in your environment. You also need to configure the PubnubSubscribeKey in your environment so the client
+can subscribe to the channel. As channel name we used webex since flint registers for webhooks with
+resource:all event: all ( we also publish to webex.${resource} and webex.${resource}.${event} so you can use 
+PubNubs channel wildcards if you want. See here https://www.pubnub.com/developers/tech/key-concepts/stream-controller/wildcard-subscribe/)
+
+When PubNub receives the event it will invoke the function that then sends the event along the channel.
+Flint spawns a bot for every space/room and will cross check based on the roomId to which bot the message
+belongs.
+
+If you want a different additional bot configured, you must use a different WebhookRecipientURL and 
+PubnubSubscribeKey Key.
+
+You should check the temaplates folder for a working example.
+```js
+"use strict";
+
+var Flint = require('node-flint');
+var webhook = require('node-flint/webhook');
+var path = require('path');
+var PubNub = require('pubnub');
+var config = require(path.join(__dirname, 'config.js'));
+var when = require('when');
+
+
+// instantiate thje pubnub object
+var pubnub = new PubNub ({
+  subscribeKey : config.pubnubSubscribeKey
+})
+
+// pubnub status listener
+// we use it here for the initialization and then remove ourselves
+let statusListener = {
+  status: (s) => {
+    if (s.category === "PNConnectedCategory") {
+      // res is from the closure
+      this.res("fullfilled my init promise for pubnub");
+    }
+  }
+}
+
+
+
+
+let messageListener = {
+  message: (m) => {
+    webhook(flint)(m.message);
+  }
+}
+
+
+
+function checkInit() {
+  return new Promise( (res,rej) => {
+    statusListener.__proto__.res = res;
+    const initTimeSecs = 5;
+    // give 3 second init time
+    setTimeout(() => {
+      rej("resolved")
+    }, initTimeSecs * 1000)
+
+    pubnub.addListener(statusListener);
+  })
+}
+
+// init flint
+var flint = new Flint(config);
+
+checkInit()
+  .then( (a) => { pubnub.removeListener(statusListener) })
+  .then( () => { flint.start() } )
+  .then( () => { flint.use(path.join(__dirname, 'flint.js')) })
+  .then( () => { flint.debug('Flint has started')  })
+  .then( () => { pubnub.addListener(messageListener) })
+  .catch( (e) => { console.log("could not init pubnub or flint") })
+
+
+// flint registers webhooks for resurce: all event: all
+// so here we listen to the all all pubnub channel
+pubnub.subscribe({
+  channels: ["webex"]
+})
+
+
+// gracefully shutdown (ctrl-c)
+process.on('SIGINT', function() {
+  flint.debug('stoppping...');
+  flint.stop().then(function() {
+    process.exit();
+  });
+});
+```

lib/utils.js

@@ -1,6 +1,7 @@
 'use strict';
 
 var uuid = require('uuid');
+var base64 = require('js-base64').Base64;
 
 var Utils = {};
 
@@ -12,7 +13,8 @@ var Utils = {};
  * @returns {String} Base64 encoded string.
  */
 Utils.base64encode = function(string) {
-  return new Buffer(string).toString('base64');
+  // deprecated return new Buffer(string).toString('base64');
+    return base64.encode(string);
 };
 
 /**

package.json

@@ -34,6 +34,8 @@
   },
   "devDependencies": {
     "doctoc": "^1.3.0",
+    "express": "^4.16.4",
+    "js-base64": "^2.4.9",
     "jsdoc-to-markdown": "^3.0.0"
   }
 }

templates/pubnub-template/Procfile

@@ -0,0 +1 @@
+web: DEBUG=flint,bot node main.js

templates/pubnub-template/README.md

@@ -0,0 +1,2 @@
+#pubnub-template
+

templates/pubnub-template/config.js

@@ -0,0 +1,12 @@
+module.exports = {
+  token: process.env.TOKEN,
+  maxPageItems: 100,
+  maxConcurrent: 5,
+  minTime: 50,
+  requeueCodes: [ 429, 500, 501, 502, 503 ],
+  requeueMinTime: 500,
+  removeWebhooksOnStart: true,
+  webhookSecret: process.env.FLYNN_APP_ID,
+  pubnubSubscribeKey: process.env.PubnubSubscribeKey,
+  webhookUrl:  process.env.WebhookRecipientURL
+};

templates/pubnub-template/flint.js

@@ -0,0 +1,7 @@
+"use strict";
+
+module.exports = function(flint) {
+  flint.hears('hello', function(bot, trigger) {
+    bot.say('Hello %s!', trigger.personDisplayName);
+  });
+};

templates/pubnub-template/main.js

@@ -0,0 +1,76 @@
+"use strict";
+
+var Flint = require('node-flint');
+var webhook = require('node-flint/webhook');
+var path = require('path');
+var PubNub = require('pubnub');
+var config = require(path.join(__dirname, 'config.js'));
+var when = require('when');
+
+
+// instantiate thje pubnub object
+var pubnub = new PubNub ({
+  subscribeKey : config.pubnubSubscribeKey
+})
+
+// pubnub status listener
+// we use it here for the initialization and then remove ourselves
+let statusListener = {
+  status: (s) => {
+    if (s.category === "PNConnectedCategory") {
+      // res is from the closure
+      this.res("fullfilled my init promise for pubnub");
+    }
+  }
+}
+
+
+
+
+let messageListener = {
+  message: (m) => {
+    webhook(flint)(m.message);
+  }
+}
+
+
+
+function checkInit() {
+  return new Promise( (res,rej) => {
+    statusListener.__proto__.res = res;
+    const initTimeSecs = 5;
+    // give 3 second init time
+    setTimeout(() => {
+      rej("resolved")
+    }, initTimeSecs * 1000)
+
+    pubnub.addListener(statusListener);
+  })
+}
+
+// init flint
+var flint = new Flint(config);
+
+checkInit()
+  .then( (a) => { pubnub.removeListener(statusListener) })
+  .then( () => { flint.start() } )
+  .then( () => { flint.use(path.join(__dirname, 'flint.js')) })
+  .then( () => { flint.debug('Flint has started')  })
+  .then( () => { pubnub.addListener(messageListener) })
+  .catch( (e) => { console.log("could not init pubnub or flint") })
+
+
+// flint registers webhooks for resurce: all event: all
+// so here we listen to the all all pubnub channel
+pubnub.subscribe({
+  channels: ["webex"]
+})
+
+
+// gracefully shutdown (ctrl-c)
+process.on('SIGINT', function() {
+  flint.debug('stoppping...');
+  flint.stop().then(function() {
+    process.exit();
+  });
+});