adds support for moving avg support in es queries

public/app/plugins/datasource/elasticsearch/query_builder.js

@@ -175,8 +175,28 @@ function () {
       }
 
       var aggField = {};
-      aggField[metric.type] = metricAgg;
+      if (metric.type === 'moving_avg') {
-      nestedAggs.aggs[metric.id] = aggField;
+        var pipeAgg = '';
+        for(var aggname in nestedAggs.aggs) {
+          var agg = nestedAggs.aggs[aggname];
+          for(prop in agg) {
+            if (agg.hasOwnProperty(prop) && agg[prop] !== null) {
+              if (metric.field === prop) {
+                pipeAgg = aggname;
+                break;
+              }
+            }
+          }
+        }
+
+        if (pipeAgg !== '') {
+          aggField[metric.type] = { buckets_path: pipeAgg };
+          nestedAggs.aggs[metric.id] = aggField;
+        }
+      } else {
+        aggField[metric.type] = metricAgg;
+        nestedAggs.aggs[metric.id] = aggField;
+      }
     }
 
     return query;
@@ -217,5 +237,4 @@ function () {
   };
 
   return ElasticQueryBuilder;
-
 });

public/app/plugins/datasource/elasticsearch/specs/query_builder_specs.ts

@@ -155,4 +155,28 @@ describe('ElasticQueryBuilder', function() {
     expect(query.size).to.be(500);
   });
 
+  it('with moving average', function() {
+    var query = builder.build({
+      metrics: [
+        {
+          id: '1',
+          type: 'sum',
+          field: '@value',
+        },
+        {
+          id: '2',
+          type: 'moving_avg',
+          field: 'sum'
+        }
+      ],
+      bucketAggs: [
+        {type: 'date_histogram', field: '@timestamp', id: '3'}
+      ],
+    });
+
+    var firstLevel = query.aggs["3"];
+    expect(firstLevel.aggs["2"]).not.to.be(undefined);
+    expect(firstLevel.aggs["2"].moving_avg).not.to.be(undefined);
+    expect(firstLevel.aggs["2"].moving_avg.buckets_path).to.be("1");
+  });
 });