Added some logic

backend/apps/authentication/serializers.py

@@ -0,0 +1,37 @@
+from django.contrib.auth.password_validation import validate_password as django_validate_password
+from django.core.exceptions import ValidationError
+from rest_framework import serializers
+from apps.user.models import User
+
+
+class RegisterSerializer(serializers.ModelSerializer):
+    
+    class Meta:
+        model = User
+        fields = ["username", "email", "password"]
+        extra_kwargs = {
+            "password": {"write_only": True}
+        }
+
+    def validate_email(self, value):
+        if User.objects.filter(email=value).exists():
+            raise serializers.ValidationError("Email already taken")
+        return value
+
+    def validate_password(self, value):
+        try:
+            django_validate_password(value)
+        except ValidationError as error:
+            raise serializers.ValidationError(error.messages)
+
+        return value
+
+    def create(self, validated_data):
+        user = User.objects.create_user(
+            validated_data["username"], 
+            validated_data["email"], 
+            validated_data["password"]
+        )
+        
+        
+        return user