feat: add listings endpoint with pagination, filters, and tests

core/serializers.py

@@ -3,6 +3,7 @@
 from rest_framework import generics, serializers
 
 from . import exceptions, models
+from .models import Listing
 from .service import CoreService
 
 
@@ -170,7 +171,7 @@ def validate(self, attrs):
         # Principal and Repayment Validation
         if attrs["principal"] > attrs["repayment_amount"]:
             raise serializers.ValidationError(
-                {"detail": "Principal should be less tha Repayment amount"}
+                {"detail": "Principal should be less than Repayment amount"}
             )
 
         # validate offer token
@@ -234,3 +235,18 @@ def validate(self, attrs):
     def save(self):
         # delete the offer
         CoreService.cancel_offer(self.validated_data["offer_id"])
+
+
+class ListingSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = Listing
+        fields = [
+            "id",
+            "nft_contract_address",
+            "nft_token_id",
+            "user",
+            "borrow_amount",
+            "duration",
+            "created_at",
+            "status",
+        ]

core/tests/factories.py

@@ -25,3 +25,29 @@ class Meta:
     @factory.lazy_attribute
     def contract_address(self):
         return "0x" + "".join(random.choices("0123456789abcdef", k=60))
+
+    token_decimal = factory.Faker("pyint", min_value=6, max_value=18)
+
+
+class UserFactory(factory.django.DjangoModelFactory):
+    class Meta:
+        model = models.User
+
+    public_key = factory.LazyFunction(
+        lambda: "0x" + "".join(random.choices("0123456789abcdef", k=60))
+    )
+
+
+class ListingFactory(factory.django.DjangoModelFactory):
+    class Meta:
+        model = models.Listing
+
+    user = factory.SubFactory("core.factories.UserFactory")
+    nft_contract_address = factory.LazyFunction(
+        lambda: "0x" + "".join(random.choices("0123456789abcdef", k=60))
+    )
+    nft_token_id = factory.Sequence(lambda n: n)
+    borrow_amount = factory.Faker("pyint", min_value=100, max_value=10000)
+    repayment_amount = factory.Faker("pyint", min_value=110, max_value=11000)
+    duration = factory.Faker("pyint", min_value=1, max_value=365)
+    status = models.ListingStatus.OPEN

core/tests/test_listings.py

@@ -0,0 +1,87 @@
+import pytest
+from django.urls import reverse
+from rest_framework.test import APIClient
+
+from core.models import ListingStatus
+from core.tests import factories
+
+
+@pytest.mark.django_db
+def test_list_active_listings():
+    client = APIClient()
+    url = reverse("listing-list")
+
+    user = factories.UserFactory()
+    active_listing = factories.ListingFactory(user=user, status=ListingStatus.OPEN)
+    factories.ListingFactory(user=user, status=ListingStatus.CLOSED)
+
+    response = client.get(url)
+    assert response.status_code == 200
+
+    data = response.json()
+    results = data["results"]
+    assert len(results) == 1
+
+    listing = results[0]
+    assert listing["id"] == str(active_listing.id)
+    assert listing["nft_contract_address"] == active_listing.nft_contract_address
+    assert listing["nft_token_id"] == active_listing.nft_token_id
+    assert listing["user"] == str(active_listing.user.id)
+    assert listing["borrow_amount"] == active_listing.borrow_amount
+    assert listing["duration"] == active_listing.duration
+    assert listing["status"] == active_listing.status
+
+
+@pytest.mark.django_db
+def test_listings_filter_by_collateral_contract():
+    client = APIClient()
+    url = reverse("listing-list")
+
+    user = factories.UserFactory()
+    factories.ListingFactory(
+        user=user, nft_contract_address="0xFilterThis", status=ListingStatus.OPEN
+    )
+
+    response = client.get(url, {"collateral_contract": "0xFilterThis"})
+    assert response.status_code == 200
+
+    data = response.json()
+    results = data["results"]
+    assert len(results) == 1
+    assert results[0]["nft_contract_address"] == "0xFilterThis"
+
+
+@pytest.mark.django_db
+def test_listings_filter_by_borrower_address():
+    client = APIClient()
+    url = reverse("listing-list")
+
+    user = factories.UserFactory(public_key="0xBorrowerFilter")
+
+    response = client.get(url, {"borrower_address": "0xBorrowerFilter"})
+    assert response.status_code == 200
+
+    data = response.json()
+    results = data["results"]
+    assert len(results) == 1
+    assert results[0]["user"] == str(user.id)
+
+
+@pytest.mark.django_db
+def test_listings_pagination_structure():
+    client = APIClient()
+    url = reverse("listing-list")
+
+    user = factories.UserFactory()
+    for _ in range(5):
+        factories.ListingFactory(user=user, status=ListingStatus.OPEN)
+
+    response = client.get(url)
+    assert response.status_code == 200
+
+    data = response.json()
+    assert "results" in data
+    assert isinstance(data["results"], list)
+    assert "count" in data
+    assert "next" in data
+    assert "previous" in data

core/urls.py

@@ -18,6 +18,11 @@
         views.SignInAPIView.as_view(),
         name="signin",
     ),
+    path(
+        "listings/",
+        views.ListingListAPIView.as_view(),
+        name="listing-list",
+    ),
     path("offer/create/", views.OfferCreateAPIView.as_view(), name="create-offer"),
     path("offer/cancel/", views.OfferCancelAPIView.as_view(), name="cancel-offer"),
 ]

core/views.py

@@ -1,10 +1,13 @@
 # Create your views here.
-from rest_framework import status
+from rest_framework import filters, status
 from rest_framework.generics import GenericAPIView, ListAPIView
+from rest_framework.pagination import PageNumberPagination
 from rest_framework.permissions import IsAuthenticated
 from rest_framework.response import Response
 
 from . import models, serializers
+from .models import Listing, ListingStatus
+from .serializers import ListingSerializer
 
 
 class AcceptedNFTListAPIView(ListAPIView):
@@ -50,3 +53,30 @@ def post(self, request):
         serializer.is_valid(raise_exception=True)
         serializer.save()
         return Response(status=status.HTTP_204_NO_CONTENT)
+
+
+class ListingPagination(PageNumberPagination):
+    page_size = 10
+    page_size_query_param = "page_size"
+    max_page_size = 100
+
+
+class ListingListAPIView(ListAPIView):
+    serializer_class = ListingSerializer
+    pagination_class = ListingPagination
+    filter_backends = [filters.SearchFilter]
+    search_fields = ["nft_contract_address", "user__public_key"]
+
+    def get_queryset(self):
+        queryset = Listing.objects.filter(status=ListingStatus.OPEN).order_by(
+            "-created_at"
+        )
+        collateral_contract = self.request.query_params.get("collateral_contract")
+        borrower_address = self.request.query_params.get("borrower_address")
+
+        if collateral_contract:
+            queryset = queryset.filter(nft_contract_address__iexact=collateral_contract)
+        if borrower_address:
+            queryset = queryset.filter(user__public_key__iexact=borrower_address)
+
+        return queryset