all attribute endpoints now working but need optimization

src/controllers/attributes.controller.js

@@ -10,6 +10,16 @@
  * NB: Check the BACKEND CHALLENGE TEMPLATE DOCUMENTATION in the readme of this repository to see our recommended
  *  endpoints, request body/param, and response object for each of these method
  */
+import {
+  Product,
+  ProductAttribute,
+  Department,
+  AttributeValue,
+  Attribute,
+  Category,
+  Sequelize,
+} from '../database/models';
+
 class AttributeController {
   /**
    * This method get all attributes
@@ -19,7 +29,12 @@ class AttributeController {
    */
   static async getAllAttributes(req, res, next) {
     // write code to get all attributes from the database here
-    return res.status(200).json({ message: 'this works' });
+    try {
+      const attributes = await Attribute.findAll();
+      return res.status(200).json(attributes);
+    } catch (error) {
+      return next(error);
+    }
   }
 
   /**
@@ -30,7 +45,21 @@ class AttributeController {
    */
   static async getSingleAttribute(req, res, next) {
     // Write code to get a single attribute using the attribute id provided in the request param
-    return res.status(200).json({ message: 'this works' });
+    const { attribute_id } = req.params; // eslint-disable-line
+    try {
+      const attribute = await Attribute.findByPk(attribute_id);
+      if (attribute) {
+        return res.status(200).json(attribute);
+      }
+      return res.status(404).json({
+        error: {
+          status: 404,
+          message: `Attribute with id ${attribute_id} does not exist`,  // eslint-disable-line
+        }
+      });
+    } catch (error) {
+      return next(error);
+    }
   }
 
   /**
@@ -42,7 +71,17 @@ class AttributeController {
   static async getAttributeValues(req, res, next) {
     // Write code to get all attribute values for an attribute using the attribute id provided in the request param
     // This function takes the param: attribute_id
-    return res.status(200).json({ message: 'this works' });
+    try {
+      const { attribute_id } = req.params; // eslint-disable-line
+      const attributeValues = await AttributeValue.findAll({
+        where: {
+          attribute_id,
+        },
+      });
+      return res.status(200).json(attributeValues);
+    } catch (error) {
+      return next(error);
+    }
   }
 
   /**
@@ -53,7 +92,33 @@ class AttributeController {
    */
   static async getProductAttributes(req, res, next) {
     // Write code to get all attribute values for a product using the product id provided in the request param
-    return res.status(200).json({ message: 'this works' });
+    try {
+      const { product_id } = req.params; // eslint-disable-line
+      const productAttributeValuesID = await ProductAttribute.findAll({
+        where: {
+          product_id,
+        },
+        attributes: ['attribute_value_id'],
+      });
+      const productAttributes = [];
+      const valuesIDArray = [];
+      productAttributeValuesID.map(id => valuesIDArray.push(id.attribute_value_id));
+      // eslint-disable-next-line no-plusplus
+      for (let i = 0; i < valuesIDArray.length; i++) {
+        // eslint-disable-next-line no-await-in-loop
+        const productAttribute = await AttributeValue.findOne({
+          where: {
+            attribute_value_id: valuesIDArray[i],
+          },
+        });
+        if (productAttribute) {
+          productAttributes.push(productAttribute)
+        }
+      }
+      return res.status(200).json(productAttributes);
+    } catch (error) {
+      return next(error);
+    }
   }
 }