(cloudwatch) don't expand variable when panel or row repeat is used (#6618)

* (cloudwatch) don't expand variable when panel or row repeat is used

* fix test

public/app/features/templating/templateSrv.js

@@ -112,10 +112,18 @@ function (angular, _, kbn) {
       this._grafanaVariables[name] = value;
     };
 
-    this.variableExists = function(expression) {
+    this.getVariableName = function(expression) {
       this._regex.lastIndex = 0;
       var match = this._regex.exec(expression);
-      return match && (self._index[match[1] || match[2]] !== void 0);
+      if (!match) {
+        return null;
+      }
+      return match[1] || match[2];
+    };
+
+    this.variableExists = function(expression) {
+      var name = this.getVariableName(expression);
+      return name && (self._index[name] !== void 0);
     };
 
     this.highlightVariablesAsHtml = function(str) {

public/app/plugins/datasource/cloudwatch/datasource.js

@@ -31,7 +31,7 @@ function (angular, _, moment, dateMath, kbn, CloudWatchAnnotationQuery) {
 
       var queries = [];
       options = angular.copy(options);
-      options.targets = this.expandTemplateVariable(options.targets, templateSrv);
+      options.targets = this.expandTemplateVariable(options.targets, options.scopedVars, templateSrv);
       _.each(options.targets, function(target) {
         if (target.hide || !target.namespace || !target.metricName || _.isEmpty(target.statistics)) {
           return;
@@ -412,12 +412,12 @@ function (angular, _, moment, dateMath, kbn, CloudWatchAnnotationQuery) {
       return str.indexOf('$' + variableName) !== -1;
     };
 
-    this.expandTemplateVariable = function(targets, templateSrv) {
+    this.expandTemplateVariable = function(targets, scopedVars, templateSrv) {
       var self = this;
       return _.chain(targets)
       .map(function(target) {
         var dimensionKey = _.findKey(target.dimensions, function(v) {
-          return templateSrv.variableExists(v);
+          return templateSrv.variableExists(v) && !_.has(scopedVars, templateSrv.getVariableName(v));
         });
 
         if (dimensionKey) {

public/app/plugins/datasource/cloudwatch/specs/datasource_specs.ts

@@ -139,6 +139,7 @@ describe('CloudWatchDatasource', function() {
             ]
           }
         ],
+        getVariableName: function (e) { return 'instance_id'; },
         variableExists: function (e) { return true; },
         containsVariable: function (str, variableName) { return str.indexOf('$' + variableName) !== -1; }
       };
@@ -156,7 +157,7 @@ describe('CloudWatchDatasource', function() {
         }
       ];
 
-      var result = ctx.ds.expandTemplateVariable(targets, templateSrv);
+      var result = ctx.ds.expandTemplateVariable(targets, {}, templateSrv);
       expect(result[0].dimensions.InstanceId).to.be('i-34567890');
     });
   });