Fix loopbackio#1795 - Count issue with related models using though model

Author: regevbr

lib/scope.js

@@ -101,7 +101,7 @@ ScopeDefinition.prototype.related = function(receiver, scopeParams, condOrRefres
       var filter = params.include;
       // The filter applied on relatedModel
       var queryRelated = filter.scope;
-      delete params.include.scope;
+      delete params.include;
     };
 
     targetModel.find(params, options, function(err, data) {
@@ -112,12 +112,13 @@ ScopeDefinition.prototype.related = function(receiver, scopeParams, condOrRefres
 
       if (scopeOnRelatedModel === true) {
         var relatedModel = targetModel.relations[filter.relation].modelTo;
+        var keyFrom = targetModel.relations[filter.relation].keyFrom;
         var IdKey = idName(relatedModel);
 
         // Merge queryRelated filter and targetId filter
         var buildWhere = function() {
           var IdKeyCondition = {};
-          IdKeyCondition[IdKey] = collectTargetIds(data, IdKey);
+          IdKeyCondition[IdKey] = collectTargetIds(data, keyFrom || IdKey);
           var mergedWhere = {
             and: [IdKeyCondition, queryRelated.where],
           };
@@ -127,7 +128,7 @@ ScopeDefinition.prototype.related = function(receiver, scopeParams, condOrRefres
           queryRelated.where = buildWhere();
         } else {
           queryRelated.where = {};
-          queryRelated.where[IdKey] = collectTargetIds(data, IdKey);
+          queryRelated.where[IdKey] = collectTargetIds(data, keyFrom || IdKey);
         }
 
         relatedModel.find(queryRelated, cb);
@@ -486,11 +487,49 @@ function defineScope(cls, targetClass, name, params, methods, options) {
       options = {};
     }
     options = options || {};
-
+    // If there is a through model
+    // run another query to apply filter on relatedModel(targetModel)
+    // see github.com/strongloop/loopback-datasource-juggler/issues/1795
+    var scopeOnRelatedModel = false;
+    if (this._scope && this._scope.collect &&
+      where !== null && typeof where === 'object') {
+      var queryRelated = {
+        relation: this._scope.collect,
+        scope: {
+          where: where,
+        },
+      };
+      where = {};
+      scopeOnRelatedModel = true;
+    }
     var targetModel = definition.targetModel(this._receiver);
     var scoped = (this._scope && this._scope.where) || {};
     var filter = mergeQuery({where: scoped}, {where: where || {}});
-    return targetModel.count(filter.where, options, cb);
+    if (!scopeOnRelatedModel) {
+      return targetModel.count(filter.where, options, cb);
+    }
+    targetModel.find(filter, options, function(err, data) {
+      var relatedModel = targetModel.relations[queryRelated.relation].modelTo;
+      var keyFrom = targetModel.relations[queryRelated.relation].keyFrom;
+      var IdKey = idName(relatedModel);
+
+      // Merge queryRelated filter and targetId filter
+      var buildWhere = function() {
+        var IdKeyCondition = {};
+        IdKeyCondition[IdKey] = collectTargetIds(data, keyFrom || IdKey);
+        var mergedWhere = {
+          and: [IdKeyCondition, queryRelated.scope.where],
+        };
+        return mergedWhere;
+      };
+      if (queryRelated.scope.where !== undefined) {
+        queryRelated.scope.where = buildWhere();
+      } else {
+        queryRelated.scope.where = {};
+        queryRelated.scope.where[IdKey] = collectTargetIds(data, keyFrom || IdKey);
+      }
+      return relatedModel.count(queryRelated.scope.where, options, cb);
+    });
   }
 
   return definition;