diff --git a/src/controllers/API.php b/src/controllers/API.php
index d5ea393..84f387f 100644
--- a/src/controllers/API.php
+++ b/src/controllers/API.php
@@ -21,8 +21,12 @@ class API
 
     public function __construct()
     {
+        // Set the Content-Type header to application/json
         header("Content-Type:application/json");
 
+        // Allow access from any origin (CORS)
+        header('Access-Control-Allow-Origin: *');
+
         $this->resource = Utility::splitURL()[2] ?? "";
     }
 
@@ -32,32 +36,83 @@ public function __construct()
      */
     private function validateURLFormat(): bool
     {
-        return preg_match("/^api\/v1/", $_GET["url"]) > 0;
+        return preg_match("/^api\/v1/", Utility::getURL()) > 0;
+    }
+
+
+    /**
+     * Returns the name of function responsible for handling the current request, as defined by the $routes variable.
+     * @param string $controllerName class name of controller
+     * @return string|null
+     */
+    private function getHandler(string $controllerName): ?string
+    {
+        $all_routes = $controllerName::$routes;
+
+        // check if there are handlers defined for current request method
+        $my_routes = $all_routes[$_SERVER['REQUEST_METHOD']] ?? "";
+        if (empty($my_routes)) {
+            return null;
+        }
+
+        foreach ($my_routes as $route => $handler) {
+            $pattern = str_replace('/', '\/', $route); // Convert to regex pattern
+            $pattern = preg_replace(
+                '/\{([a-zA-Z0-9_]+)\}/',
+                '(?P<$1>[^\/]+)',
+                $pattern
+            ); // Replace placeholders with regex capture groups
+            $pattern = '/^' . $pattern . '$/';
+
+            if (preg_match($pattern, '/' . Utility::getURL(), $matches)) {
+                return $handler;
+            }
+        }
+        return null;
     }
 
     public function index(): void
     {
         if (!$this->validateURLFormat()) {
             http_response_code(400);
-            die();
+            return;
         }
 
-        // call appropriate controller to handle resource
+        // check if there is a controller to handle resource
         $controllerClassName = 'Steamy\\Controller\\API\\' . ucfirst($this->resource);
+        if (!class_exists($controllerClassName)) {
+            // no controller available
+            http_response_code(404);
+            echo 'Invalid resource: ' . $this->resource; // comment this line for production
+            return;
+        }
+
+        // determine which function to call in the controller to handle route
+        $functionName = $this->getHandler($controllerClassName);
+        if ($functionName === null) {
+            // Controller does not have any method defined for route
+            http_response_code(404);
+            echo "Request has not been defined in \$routes for " . $controllerClassName;
+            return;
+        }
+
+        $controller = new $controllerClassName();
+
+        if (!method_exists($controller, $functionName)) {
+            // handle function not found in controller
+            http_response_code(500);
+            echo $controllerClassName . ' does not have a public method ' . $functionName;
+            return;
+        }
+
+        // call function in controller for handling request
         try {
-            if (class_exists($controllerClassName)) {
-                (new $controllerClassName())->index();
-            } else {
-                http_response_code(404);
-                die();
-            }
+            call_user_func(array($controller, $functionName));
         } catch (Exception $e) {
             http_response_code(500);
 
             // Uncomment line below only when testing API
             echo $e->getMessage();
-
-            die();
         }
     }
 }
diff --git a/src/controllers/api/Districts.php b/src/controllers/api/Districts.php
index 7d3ed3a..ea0f610 100644
--- a/src/controllers/api/Districts.php
+++ b/src/controllers/api/Districts.php
@@ -12,10 +12,17 @@ class Districts
 {
     use Model;
 
+    public static array $routes = [
+        'GET' => [
+            '/api/v1/districts' => 'getAllDistricts',
+            '/api/v1/districts/{id}' => 'getDistrictById',
+        ]
+    ];
+
     /**
      * Get the list of all districts available.
      */
-    private function getAllDistricts(): void
+    public function getAllDistricts(): void
     {
         // Retrieve all districts from the database
         $allDistricts = District::getAll();
@@ -36,7 +43,7 @@ private function getAllDistricts(): void
     /**
      * Get the details of a specific district by its ID.
      */
-    private function getDistrictById(): void
+    public function getDistrictById(): void
     {
         $districtId = (int)Utility::splitURL()[3];
 
@@ -57,55 +64,4 @@ private function getDistrictById(): void
             'name' => $district->getName()
         ]);
     }
-
-    private function getHandler($routes): ?string
-    {
-        foreach ($routes[$_SERVER['REQUEST_METHOD']] as $route => $handler) {
-            $pattern = str_replace('/', '\/', $route); // Convert to regex pattern
-            $pattern = preg_replace(
-                '/\{([a-zA-Z0-9_]+)\}/',
-                '(?P<$1>[^\/]+)',
-                $pattern
-            ); // Replace placeholders with regex capture groups
-            $pattern = '/^' . $pattern . '$/';
-
-            if (preg_match($pattern, '/' . Utility::getURL(), $matches)) {
-                return $handler;
-            }
-        }
-        return null;
-    }
-
-    /**
-     * Main entry point for the Districts API.
-     */
-    public function index(): void
-    {
-        $routes = [
-            'GET' => [
-                '/api/v1/districts' => 'getAllDistricts',
-                '/api/v1/districts/{id}' => 'getDistrictById',
-            ]
-        ];
-
-        // Handle the request
-        $handler = $this->getHandler($routes);
-
-        if ($handler !== null) {
-            $functionName = $handler;
-            if (method_exists($this, $functionName)) {
-                call_user_func(array($this, $functionName));
-            } else {
-                // Handle function not found
-                http_response_code(404);
-                echo "Function Not Found";
-                die();
-            }
-        } else {
-            // Handle route not found
-            http_response_code(404);
-            echo "Route Not Found";
-            die();
-        }
-    }
 }
diff --git a/src/controllers/api/Products.php b/src/controllers/api/Products.php
index 978005d..dc87b10 100644
--- a/src/controllers/api/Products.php
+++ b/src/controllers/api/Products.php
@@ -12,10 +12,27 @@ class Products
 {
     use Model;
 
+    public static array $routes = [
+        'GET' => [
+            '/api/v1/products' => 'getAllProducts',
+            '/api/v1/products/categories' => 'getProductCategories',
+            '/api/v1/products/{id}' => 'getProductById',
+        ],
+        'POST' => [
+            '/api/v1/products' => 'createProduct',
+        ],
+        'PUT' => [
+            '/api/v1/products/{id}' => 'updateProduct',
+        ],
+        'DELETE' => [
+            '/api/v1/products/{id}' => 'deleteProduct',
+        ]
+    ];
+
     /**
      * Get the list of all products available in the store.
      */
-    private function getAllProducts(): void
+    public function getAllProducts(): void
     {
         // Retrieve all products from the database
         $allProducts = Product::getAll();
@@ -33,7 +50,7 @@ private function getAllProducts(): void
     /**
      * Get the details of a specific product by its ID.
      */
-    private function getProductById(): void
+    public function getProductById(): void
     {
         $productId = (int)Utility::splitURL()[3];
 
@@ -55,7 +72,7 @@ private function getProductById(): void
     /**
      * Get the list of product categories.
      */
-    private function getProductCategories(): void
+    public function getProductCategories(): void
     {
         // Retrieve all product categories from the database
         $categories = Product::getCategories();
@@ -67,7 +84,7 @@ private function getProductCategories(): void
     /**
      * Create a new product entry in the database.
      */
-    private function createProduct(): void
+    public function createProduct(): void
     {
         // Retrieve POST data
         $postData = $_POST;
@@ -126,7 +143,7 @@ private function createProduct(): void
     /**
      * Delete a product with the specified ID.
      */
-    private function deleteProduct(): void
+    public function deleteProduct(): void
     {
         $productId = (int)Utility::splitURL()[3];
 
@@ -155,7 +172,7 @@ private function deleteProduct(): void
     /**
      * Update the details of a product with the specified ID.
      */
-    private function updateProduct(): void
+    public function updateProduct(): void
     {
         $productId = (int)Utility::splitURL()[3];
 
@@ -194,65 +211,4 @@ private function updateProduct(): void
             echo json_encode(['error' => 'Failed to update product']);
         }
     }
-
-    private function getHandler($routes): ?string
-    {
-        foreach ($routes[$_SERVER['REQUEST_METHOD']] as $route => $handler) {
-            $pattern = str_replace('/', '\/', $route); // Convert to regex pattern
-            $pattern = preg_replace(
-                '/\{([a-zA-Z0-9_]+)\}/',
-                '(?P<$1>[^\/]+)',
-                $pattern
-            ); // Replace placeholders with regex capture groups
-            $pattern = '/^' . $pattern . '$/';
-
-            if (preg_match($pattern, '/' . Utility::getURL(), $matches)) {
-                return $handler;
-            }
-        }
-        return null;
-    }
-
-    /**
-     * Main entry point for the Products API.
-     */
-    public function index(): void
-    {
-        $routes = [
-            'GET' => [
-                '/api/v1/products' => 'getAllProducts',
-                '/api/v1/products/categories' => 'getProductCategories',
-                '/api/v1/products/{id}' => 'getProductById',
-            ],
-            'POST' => [
-                '/api/v1/products' => 'createProduct',
-            ],
-            'PUT' => [
-                '/api/v1/products/{id}' => 'updateProduct',
-            ],
-            'DELETE' => [
-                '/api/v1/products/{id}' => 'deleteProduct',
-            ]
-        ];
-
-        // Handle the request
-        $handler = $this->getHandler($routes);
-
-        if ($handler !== null) {
-            $functionName = $handler;
-            if (method_exists($this, $functionName)) {
-                call_user_func(array($this, $functionName));
-            } else {
-                // Handle function not found
-                http_response_code(404);
-                echo "Function Not Found";
-                die();
-            }
-        } else {
-            // Handle route not found
-            http_response_code(404);
-            echo "Route Not Found";
-            die();
-        }
-    }
 }
diff --git a/src/controllers/api/Reviews.php b/src/controllers/api/Reviews.php
index 015c0aa..bfbcc9f 100644
--- a/src/controllers/api/Reviews.php
+++ b/src/controllers/api/Reviews.php
@@ -6,14 +6,31 @@
 
 use Steamy\Core\Utility;
 use Steamy\Model\Review;
+use \Steamy\Model\Product as ProductModel;
 
 class Reviews
 {
 
+    public static array $routes = [
+        'GET' => [
+            '/api/v1/reviews' => 'getAllReviews',
+            '/api/v1/products/{id}/reviews' => 'getAllReviewsForProduct',
+        ],
+        'POST' => [
+            '/api/v1/reviews' => 'createReview',
+        ],
+        'PUT' => [
+            '/api/v1/reviews/{id}' => 'updateReview',
+        ],
+        'DELETE' => [
+            '/api/v1/reviews/{id}' => 'deleteReview',
+        ]
+    ];
+
     /**
      * Get the list of all reviews available.
      */
-    private function getAllReviews(): void
+    public function getAllReviews(): void
     {
         // Retrieve all reviews from the database
         $allReviews = Review::getAll();
@@ -31,21 +48,21 @@ private function getAllReviews(): void
     /**
      * Get all reviews for a particular product by its ID.
      */
-    private function getAllReviewsForProduct(): void
+    public function getAllReviewsForProduct(): void
     {
         $productId = (int)Utility::splitURL()[4];
 
-        // Retrieve all reviews for the specified product from the database
-        $reviews = Review::getAllReviewsForProduct($productId);
-
-        // Check if Review exists
-        if ($reviews === null) {
-            // Review not found, return 404
+        // Check if product exists
+        if (ProductModel::getById($productId) === null) {
+            // product not found, return 404
             http_response_code(404);
-            echo json_encode(['error' => 'Review not found']);
+            echo json_encode(['error' => 'Product not found']);
             return;
         }
 
+        // Retrieve all reviews for the specified product from the database
+        $reviews = Review::getAllReviewsForProduct($productId);
+
         // Return JSON response
         echo json_encode($reviews);
     }
@@ -53,13 +70,13 @@ private function getAllReviewsForProduct(): void
     /**
      * Create a new review for a product.
      */
-    private function createReview(): void
+    public function createReview(): void
     {
         // Retrieve POST data
         $postData = $_POST;
 
         // TODO: Implement validation for required fields and data types
-                // Check if required fields are present
+        // Check if required fields are present
         $requiredFields = [
             'product_id',
             'client_id',
@@ -105,7 +122,7 @@ private function createReview(): void
     /**
      * Update the details of a review with the specified ID.
      */
-    private function updateReview(): void
+    public function updateReview(): void
     {
         $reviewId = (int)Utility::splitURL()[3];
 
@@ -148,7 +165,7 @@ private function updateReview(): void
     /**
      * Delete a review with the specified ID.
      */
-    private function deleteReview(): void
+    public function deleteReview(): void
     {
         $reviewId = (int)Utility::splitURL()[3];
 
@@ -173,64 +190,4 @@ private function deleteReview(): void
             echo json_encode(['error' => 'Failed to delete review']);
         }
     }
-
-    private function getHandler($routes): ?string
-    {
-        foreach ($routes[$_SERVER['REQUEST_METHOD']] as $route => $handler) {
-            $pattern = str_replace('/', '\/', $route); // Convert to regex pattern
-            $pattern = preg_replace(
-                '/\{([a-zA-Z0-9_]+)\}/',
-                '(?P<$1>[^\/]+)',
-                $pattern
-            ); // Replace placeholders with regex capture groups
-            $pattern = '/^' . $pattern . '$/';
-
-            if (preg_match($pattern, '/' . Utility::getURL(), $matches)) {
-                return $handler;
-            }
-        }
-        return null;
-    }
-
-    /**
-     * Main entry point for the Reviews API.
-     */
-    public function index(): void
-    {
-        $routes = [
-            'GET' => [
-                '/api/v1/reviews' => 'getAllReviews',
-                '/api/v1/products/{id}/reviews' => 'getAllReviewsForProduct',
-            ],
-            'POST' => [
-                '/api/v1/reviews' => 'createReview',
-            ],
-            'PUT' => [
-                '/api/v1/reviews/{id}' => 'updateReview',
-            ],
-            'DELETE' => [
-                '/api/v1/reviews/{id}' => 'deleteReview',
-            ]
-        ];
-
-        // Handle the request
-        $handler = $this->getHandler($routes);
-
-        if ($handler !== null) {
-            $functionName = $handler;
-            if (method_exists($this, $functionName)) {
-                call_user_func([$this, $functionName]);
-            } else {
-                // Handle function not found
-                http_response_code(404);
-                echo "Function Not Found";
-                die();
-            }
-        } else {
-            // Handle route not found
-            http_response_code(404);
-            echo "Route Not Found";
-            die();
-        }
-    }
 }
diff --git a/src/controllers/api/Sessions.php b/src/controllers/api/Sessions.php
index 48d559c..537c7c3 100644
--- a/src/controllers/api/Sessions.php
+++ b/src/controllers/api/Sessions.php
@@ -11,7 +11,14 @@
  */
 class Sessions
 {
-    private function handleLogin(): void
+
+    public static array $routes = [
+        'POST' => [
+            '/api/v1/products' => 'handleLogin',
+        ]
+    ];
+
+    public function handleLogin(): void
     {
         $email = trim($_POST['email'] ?? "");
         $password = trim($_POST['password'] ?? "");
@@ -39,16 +46,4 @@ private function handleLogin(): void
         $_SESSION['admin_email'] = $email;
         session_regenerate_id();
     }
-
-    public function index(): void
-    {
-        switch ($_SERVER['REQUEST_METHOD']) {
-            case 'POST':
-                $this->handleLogin();
-                break;
-            default:
-                http_response_code(400);
-                die();
-        }
-    }
 }
\ No newline at end of file