added db router with random algo for now

api/dbrouter.py

@@ -0,0 +1,33 @@
+import random
+
+class PrimaryReplicaRouter:
+    def db_for_read(self, model, **hints):
+        """
+        Reads go to a randomly-chosen replica.
+        """
+        db_to = random.choice(['replica1', 'replica2'])
+        print('****'*20)
+        print(db_to)
+        return db_to 
+
+    def db_for_write(self, model, **hints):
+        """
+        Writes always go to primary.
+        """
+        return 'primary'
+
+    def allow_relation(self, obj1, obj2, **hints):
+        """
+        Relations between objects are allowed if both objects are
+        in the primary/replica pool.
+        """
+        db_set = {'primary', 'replica1', 'replica2'}
+        if obj1._state.db in db_set and obj2._state.db in db_set:
+            return True
+        return None
+
+    def allow_migrate(self, db, app_label, model_name=None, **hints):
+        """
+        All non-auth models end up in this pool.
+        """
+        return True

api/views.py

@@ -17,7 +17,7 @@ def get(self, request, format=None):
         category = Category.objects.get(id=category_id)
         subcategories = SubCategory.objects.filter(category=category)
         subcategories_prefetch = Prefetch('sub_category', queryset=subcategories)
-        products = Product.objects.filter(sub_category__in=subcategories).prefetch_related(subcategories_prefetch)
+        products = Product.objects.filter(sub_category__in=subcategories).prefetch_related(subcategories_prefetch).order_by('id') #to get uniform paginated results.
         #products = Product.objects.filter(sub_category__in=subcategories)
 
         paginator = Paginator(products, 10)

dbroutertest.py

@@ -0,0 +1,13 @@
+import requests
+
+def callapi():
+    url = "http://localhost:8000/api/products-by-category?category=21&page=2"
+
+    payload = {}
+    headers = {}
+
+    response = requests.request("GET", url, headers=headers, data=payload)
+
+for i in range(0,100):
+    callapi()
+

globalmart/settings.py

@@ -105,7 +105,8 @@
 # https://docs.djangoproject.com/en/4.2/ref/settings/#databases
 
 DATABASES = {
-    "default": {
+    'default': {},
+    "primary": {
         "ENGINE": "django.db.backends.postgresql",
         "NAME": "globalmart",
         "USER": "postgres",
@@ -131,7 +132,7 @@
     }
 }
 
-
+DATABASE_ROUTERS = ['api.dbrouter.PrimaryReplicaRouter']
 
 # Password validation
 # https://docs.djangoproject.com/en/4.2/ref/settings/#auth-password-validators