Adding cheerlights.js file

cheerlights.js

@@ -0,0 +1,51 @@
+// CheerLights client library for connecting to thingspeak.com
+
+// namespace for cheerlights
+var CheerLights = {
+  // base domain of thingspeak
+  domainThingSpeak: 'https://api.thingspeak.com/',
+  // thingspeak channel for cheerlights
+  channelThingSpeak: 1417
+};
+
+// get the latest color value
+CheerLights.getColor = function(callback) {
+
+  // contruct URL for thingspeak
+  var url = CheerLights.domainThingSpeak + 'channels/' + CheerLights.channelThingSpeak + '/feeds/last.json';
+
+  // send color request to thingspeak
+  CheerLights.ajaxColorFromThingSpeak(url, callback);
+
+}
+
+// get channel data from thingspeak
+CheerLights.ajaxColorFromThingSpeak = function(url, callback) {
+
+  // set up new request
+  const request = new XMLHttpRequest();
+  request.open('GET', url, true);
+  request.send();
+
+  // callback when the response is received
+  request.onload = function() {
+    // successful response
+    if (request.status >= 200 && request.status < 400) {
+      // get response text
+      response = request.responseText;
+
+      // parse response
+      response = JSON.parse(response);
+
+      // set color values
+      const color = {
+        htmlName: response.field1,
+        hexValue: response.field2
+      };
+
+      // execute the callback if it is a function
+      if (typeof callback === 'function') { callback(color); }
+    }
+  };
+
+}