Restoring calendar handler

Author: Gavin Barron

CalendarWebHookHandler/function.json

@@ -0,0 +1,16 @@
+{
+  "bindings": [
+    {
+      "type": "httpTrigger",
+      "direction": "in",
+      "name": "req",
+      "authLevel": "anonymous"
+    },
+    {
+      "type": "http",
+      "direction": "out",
+      "name": "res"
+    }
+  ],
+  "disabled": false
+}

CalendarWebHookHandler/index.js

@@ -0,0 +1,64 @@
+const azureStorage = require('azure-storage');
+const cfg = require('../common/config')
+
+module.exports = function (context, data) {
+    context.log('Calendar Webhook Handler was triggered!');
+
+    // Handle subscription request
+    if (data.query.validationToken) {
+        context.log('registering new hook');
+        context.res = {
+            status: 200,
+            body: data.query.validationToken
+        };
+        context.done();
+        return;
+    }
+
+    const storageConnectionString = process.env.AzureWebJobsStorage;
+    const queueSvc = azureStorage.createQueueService(storageConnectionString);
+    // Write incoming notifications onto a queue.
+    queueSvc.createQueueIfNotExists('hook-recieved', err => {
+        if (err) {
+            // this should be a log for the dev, not a message to the user
+            context.log('There was an error creating the hook-recieved queue: '+ err);
+            context.done(err);
+            return;
+        }
+        // enqueue a message to process the webhook request.
+        const request = data.body;
+        context.log(request);
+        const notificationCount = request.value.length;
+        let processed = 0;
+        // web hook requests can contain multiple notifications
+        for (let hook of request.value) {
+            let msg = JSON.stringify(hook);
+            context.log(msg);
+            var queueMessageBuffer = new Buffer(msg).toString('base64');
+            // only take action when the clientState is vaild.
+            // return the 202 and do notthing if the clientState is vaild.
+            if (hook.clientState !== cfg.CLIENT_STATE) {
+                // add a log entry so that this can be investigated
+                context.log('Unknown sender! Investigate the source of this message')
+                context.log(data);
+                context.res = { status: 202, body: 'All notifications processed' };
+                context.done();
+                return;
+            }
+            queueSvc.createMessage('hook-recieved', queueMessageBuffer, (err, result) => {
+                processed++;
+                // fail on any message not getting queued properly
+                if (err) {
+                    context.log('error sending webhook messge on hook-recieved queue');
+                    context.done(err);
+                    return;
+                }
+                context.log('webhook messge on put onto hook-recieved queue');
+                if (processed == notificationCount) {
+                    context.res = { status: 202, body: 'All notifications processed' };
+                    context.done(null, result);
+                }
+            });
+        }
+    });
+}

EventWebHookHandler/function.json

@@ -4,7 +4,7 @@
       "type": "httpTrigger",
       "direction": "in",
       "name": "req",
-      "authLevel": "anonymous"
+      "authLevel": "function"
     },
     {
       "type": "http",