make graph viewer issue less expensive queries

js/apps/system/_admin/aardvark/APP/frontend/js/graphViewer/graph/gharialAdapter.js

@@ -153,12 +153,38 @@ function GharialAdapter(nodes, edges, viewer, config) {
       });
     },
 
-    getNRandom = function(n, callback) {
-      sendQuery(queries.randomVertices, {
-        limit: n
-      }, function(res) {
-        callback(res);
+    getNRandom = function(n, collection) {
+      var data = {
+        query: queries.randomVertices,
+        bindVars: {
+          "@collection" : collection,
+          limit: n
+        }
+      };
+      var result;
+
+      $.ajax({
+        type: "POST",
+        url: api.cursor,
+        data: JSON.stringify(data),
+        contentType: "application/json",
+        dataType: "json",
+        processData: false,
+        async: false,
+        success: function(data) {
+          result = data.result;
+        },
+        error: function(data) {
+          try {
+            console.log(data.statusText);
+            throw "[" + data.errorNum + "] " + data.errorMessage;
+          }
+          catch (e) {
+            throw "Undefined ERROR";
+          }
+        }
       });
+      return result;
     },
 
     parseResultOfTraversal = function (result, callback) {
@@ -233,7 +259,7 @@ function GharialAdapter(nodes, edges, viewer, config) {
       + "})";
   queries.childrenCentrality = "RETURN LENGTH(GRAPH_EDGES(@graph, @id, {direction: any}))";
   queries.connectedEdges = "RETURN GRAPH_EDGES(@graph, @id)";
-  queries.randomVertices = "FOR x IN GRAPH_VERTICES(@graph, {}) SORT RAND() LIMIT @limit RETURN x";
+  queries.randomVertices = "FOR x IN @@collection SORT RAND() LIMIT @limit RETURN x";
 
   self.explore = absAdapter.explore;
 
@@ -242,13 +268,18 @@ function GharialAdapter(nodes, edges, viewer, config) {
   };
 
   self.loadRandomNode = function(callback) {
-    getNRandom(1, function(list) {
-      if (list.length === 0) {
-        callback({errorCode: 404});
+    var collections = _.shuffle(self.getNodeCollections()), i;
+    for (i = 0; i < collections.length; ++i) {
+      var list = getNRandom(1, collections[i]);
+      
+      if (list.length > 0) {
+        self.loadInitialNode(list[0]._id, callback);
         return;
       }
-      self.loadInitialNode(list[0]._id, callback);
-    });
+    }
+
+    // no vertex found
+    callback({errorCode: 404});
   };
 
   self.loadInitialNode = function(nodeId, callback) {
@@ -457,20 +488,27 @@ function GharialAdapter(nodes, edges, viewer, config) {
 
   self.getAttributeExamples = function(callback) {
     if (callback && callback.length >= 1) {
-      getNRandom(10, function(l) {
-        var ret = _.sortBy(
-          _.uniq(
-            _.flatten(
-              _.map(l, function(o) {
-                return _.keys(o);
-              })
-            )
-          ), function(e) {
-            return e.toLowerCase();
-          }
-        );
-        callback(ret);
-      });
+      var ret = [ ];
+      var collections = _.shuffle(self.getNodeCollections()), i;
+      for (i = 0; i < collections.length; ++i) {
+        var l = getNRandom(10, collections[i]);
+      
+        if (l.length > 0) {
+          ret = ret.concat(_.flatten(
+           _.map(l, function(o) {
+             return _.keys(o);
+           })
+          ));
+        }
+      }
+          
+      var ret = _.sortBy(
+        _.uniq(ret), function(e) {
+          return e.toLowerCase();
+        }
+      );
+
+      callback(ret);
     }
   };