add realtionshipAttributes filtering

Author: vdvibhu20

lib/baseController.js

@@ -29,7 +29,8 @@ class Controller {
       'handleReview',
       'handlePublish',
       'get',
-      'getExcludedAttributes'
+      'getExcludedAttributes',
+      'generateRelationshipAttributeClause'
     ).forEach(methodName => {
       this[methodName] = this[methodName].bind(this)
     })
@@ -141,6 +142,14 @@ class Controller {
     return null
   }
 
+  generateRelationshipAttributeClause (req, modelName) {
+    if (!req) return null
+    const {fields} = req.query
+    if(!fields) return null
+    const attributes = fields[modelName] ? fields[modelName].split(',') : null
+    return attributes
+  }
+
   // construct a Sorting Condition(value for sequelize sort: key) based on req.query.sort
   generateSortingCondition (req) {
     if (!req.query.sort) return []
@@ -177,7 +186,8 @@ class Controller {
 
         const includeObj = {
           model: model.target,
-          where: this.generateRelationshipWhereClause(req, modelName)
+          where: this.generateRelationshipWhereClause(req, modelName),
+          attributes: this.generateRelationshipAttributeClause(req, modelName)
         }
 
         if (model.isAliased) {