Streamer event upload to Azure function. (#343)

* Uploading event data to azure function endpoint to broadcast to end clients.

test/vm-cluster/stream.js

@@ -14,7 +14,7 @@ let keys = null;
 let vultrApiKey = null;
 let azureTable = null;
 let tableSvc = null;
-const queue = [];
+const clusterQueues = {};
 const metrics = {};
 const nodeGroups = {};
 
@@ -58,7 +58,7 @@ async function main() {
 
     // Start event dispatcher.
     // This keeps sending events to the ingestion endpoint.
-    eventDispatcher();
+    eventDispatcher(config.azure_function.host, config.azure_function.path);
 
     // Start event metrics tracker.
     // metricsTracker();
@@ -75,18 +75,43 @@ async function resolveHosts(cluster) {
     console.log(`${cluster.hosts.length} hosts in '${cluster.name}' cluster.`)
 }
 
-function eventDispatcher() {
-
+function eventDispatcher(hostname, path) {
     // Dispatch all queued events in batches.
-    const events = queue.splice(0);
+    while (true) {
+        obj = {};
+        for (const [cluster, data] of Object.entries(clusterQueues)) {
+            if (data.length > eventsBatchSize) {
+                obj[cluster] = data.splice(0, eventsBatchSize);
+            }
+            else if (data.length > 0) {
+                obj[cluster] = data.splice(0);
+            }
+        }
+        // Break the loop if there is no event data remaining.
+        if (Object.keys(obj).length == 0)
+            break;
 
-    for (let i = 0, j = events.length; i < j; i += eventsBatchSize) {
-        const batch = events.slice(i, i + eventsBatchSize);
+        const data = JSON.stringify(obj);
+        const req = https.request({
+            hostname: hostname,
+            port: 443,
+            path: path,
+            method: 'POST',
+            headers: {
+                'Content-Type': 'application/json',
+                'Content-Length': data.length
+            }
+        });
 
-        // TODO: Upload batch of events.
+        req.on('error', error => {
+            console.error(error);
+        })
+
+        req.write(data);
+        req.end();
     }
 
-    setTimeout(() => eventDispatcher(), dispatchInterval);
+    setTimeout(() => eventDispatcher(hostname, path), dispatchInterval);
 }
 
 function nodeStateUploader() {
@@ -205,7 +230,10 @@ async function reportEvent(node, ev) {
 
     const ts = new Date().getTime(); // Epoch milliseconds.
 
-    queue.push({
+    if (!clusterQueues[node.cluster])
+        clusterQueues[node.cluster] = [];
+
+    clusterQueues[node.cluster].push({
         cluster: node.cluster,
         idx: node.idx,
         uri: node.uri,
@@ -226,7 +254,7 @@ async function reportEvent(node, ev) {
     else if (ev.event == 'offline') {
         node.status = 'offline';
     }
-    
+
     node.hasUpdates = true;
     node.lastUpdated = ts;