Code cleanup part #1: move all the services and directive JS code in the app.js file into its own files

static/js/services/ping-service.js

@@ -0,0 +1,99 @@
+/**
+ * Service which pings an endpoint URL and estimates the latency to it.
+ */
+angular.module('quay').factory('PingService', [function() {
+  var pingService = {};
+  var pingCache = {};
+
+  var invokeCallback = function($scope, pings, callback) {
+    if (pings[0] == -1) {
+      setTimeout(function() {
+        $scope.$apply(function() {
+          callback(-1, false, -1);
+        });
+      }, 0);
+      return;
+    }
+
+    var sum = 0;
+    for (var i = 0; i < pings.length; ++i) {
+      sum += pings[i];
+    }
+
+    // Report the average ping.
+    setTimeout(function() {
+      $scope.$apply(function() {
+        callback(Math.floor(sum / pings.length), true, pings.length);
+      });
+    }, 0);
+  };
+
+  var reportPingResult = function($scope, url, ping, callback) {
+    // Lookup the cached ping data, if any.
+    var cached = pingCache[url];
+    if (!cached) {
+      cached = pingCache[url] = {
+        'pings': []
+      };
+    }
+
+    // If an error occurred, report it and done.
+    if (ping < 0) {
+      cached['pings'] = [-1];
+      invokeCallback($scope, [-1], callback);
+      return;
+    }
+
+    // Otherwise, add the current ping and determine the average.
+    cached['pings'].push(ping);
+
+    // Invoke the callback.
+    invokeCallback($scope, cached['pings'], callback);
+
+    // Schedule another check if we've done less than three.
+    if (cached['pings'].length < 3) {
+      setTimeout(function() {
+        pingUrlInternal($scope, url, callback);
+      }, 1000);
+    }
+  };
+
+  var pingUrlInternal = function($scope, url, callback) {
+    var path = url + '?cb=' + (Math.random() * 100);
+    var start = new Date();
+    var xhr = new XMLHttpRequest();
+    xhr.onerror = function() {
+          reportPingResult($scope, url, -1, callback);
+    };
+
+    xhr.onreadystatechange = function () {
+      if (xhr.readyState === xhr.HEADERS_RECEIVED) {
+        if (xhr.status != 200) {
+              reportPingResult($scope, url, -1, callback);
+          return;
+        }
+
+            var ping = (new Date() - start);
+            reportPingResult($scope, url, ping, callback);
+      }
+    };
+
+    xhr.open("GET", path);
+    xhr.send(null);
+  };
+
+  pingService.pingUrl = function($scope, url, callback) {
+    if (pingCache[url]) {
+      invokeCallback($scope, pingCache[url]['pings'], callback);
+      return;
+    }
+
+    // Note: We do each in a callback after 1s to prevent it running when other code
+    // runs (which can skew the results).
+    setTimeout(function() {
+      pingUrlInternal($scope, url, callback);
+    }, 1000);
+  };
+
+  return pingService;
+}]);