From 2c91b1ad261a6e0bac5ba3be5cc96a3d1a399e02 Mon Sep 17 00:00:00 2001
From: Fabricio Aguiar <fabricio.aguiar@gmail.com>
Date: Tue, 1 Sep 2020 12:11:49 -0300
Subject: [PATCH] Changed V3 pagination to match Galaxy V3 API pagination

https://pulp.plan.io/issues/7435
closes #7435
---
 CHANGES/7435.removal                          |  1 +
 pulp_ansible/app/galaxy/v3/pagination.py      | 84 +++++++++++++++++++
 pulp_ansible/app/galaxy/v3/views.py           |  3 +
 pulp_ansible/app/galaxy/views.py              |  1 +
 .../api/collection/v3/test_collection.py      |  4 +-
 5 files changed, 91 insertions(+), 2 deletions(-)
 create mode 100644 CHANGES/7435.removal
 create mode 100644 pulp_ansible/app/galaxy/v3/pagination.py

diff --git a/CHANGES/7435.removal b/CHANGES/7435.removal
new file mode 100644
index 000000000..1191e01cc
--- /dev/null
+++ b/CHANGES/7435.removal
@@ -0,0 +1 @@
+Changed V3 pagination to match Galaxy V3 API pagination
diff --git a/pulp_ansible/app/galaxy/v3/pagination.py b/pulp_ansible/app/galaxy/v3/pagination.py
new file mode 100644
index 000000000..64c7806df
--- /dev/null
+++ b/pulp_ansible/app/galaxy/v3/pagination.py
@@ -0,0 +1,84 @@
+from rest_framework import pagination
+from rest_framework.response import Response
+from rest_framework.utils.urls import remove_query_param, replace_query_param
+
+
+class LimitOffsetPagination(pagination.LimitOffsetPagination):
+    """
+    Pagination for V3.
+
+    """
+
+    default_limit = 10
+    max_limit = 100
+
+    def get_first_link(self):
+        """First link."""
+        url = self.request.get_full_path()
+        url = replace_query_param(url, self.limit_query_param, self.limit)
+
+        return replace_query_param(url, self.offset_query_param, 0)
+
+    def get_last_link(self):
+        """Last link."""
+        url = self.request.get_full_path()
+        url = replace_query_param(url, self.limit_query_param, self.limit)
+
+        offset = self.count - self.limit if (self.count - self.limit) >= 0 else 0
+        return replace_query_param(url, self.offset_query_param, offset)
+
+    def get_next_link(self):
+        """Next link."""
+        if self.offset + self.limit >= self.count:
+            return None
+
+        url = self.request.get_full_path()
+        url = replace_query_param(url, self.limit_query_param, self.limit)
+
+        offset = self.offset + self.limit
+        return replace_query_param(url, self.offset_query_param, offset)
+
+    def get_previous_link(self):
+        """Previous link."""
+        if self.offset <= 0:
+            return None
+
+        url = self.request.get_full_path()
+        url = replace_query_param(url, self.limit_query_param, self.limit)
+
+        if self.offset - self.limit <= 0:
+            return remove_query_param(url, self.offset_query_param)
+
+        offset = self.offset - self.limit
+        return replace_query_param(url, self.offset_query_param, offset)
+
+    def get_paginated_response(self, data):
+        """Returns paginated response."""
+        return Response(
+            {
+                "meta": {"count": self.count},
+                "links": {
+                    "first": self.get_first_link(),
+                    "previous": self.get_previous_link(),
+                    "next": self.get_next_link(),
+                    "last": self.get_last_link(),
+                },
+                "data": data,
+            }
+        )
+
+    # Custom methods for working with pulp client
+    def init_from_request(self, request):
+        """Init form request."""
+        self.request = request
+        self.offset = self.get_offset(request)
+        self.limit = self.get_limit(request)
+
+    def paginate_proxy_response(self, data, count):
+        """Paginate proxy response."""
+        self.count = count
+
+        if self.count > self.limit and self.template is not None:
+            self.display_page_controls = True
+
+        return self.get_paginated_response(data)
diff --git a/pulp_ansible/app/galaxy/v3/views.py b/pulp_ansible/app/galaxy/v3/views.py
index 9955330ac..91cf0136f 100644
--- a/pulp_ansible/app/galaxy/v3/views.py
+++ b/pulp_ansible/app/galaxy/v3/views.py
@@ -30,6 +30,7 @@
 )
 
 from pulp_ansible.app.galaxy.mixins import UploadGalaxyCollectionMixin
+from pulp_ansible.app.galaxy.v3.pagination import LimitOffsetPagination
 from pulp_ansible.app.viewsets import CollectionVersionFilter
 
 
@@ -73,6 +74,7 @@ class CollectionViewSet(
     authentication_classes = []
     permission_classes = []
     serializer_class = CollectionSerializer
+    pagination_class = LimitOffsetPagination
 
     def get_queryset(self):
         """
@@ -184,6 +186,7 @@ class CollectionVersionViewSet(
     permission_classes = []
     serializer_class = CollectionVersionSerializer
     filterset_class = CollectionVersionFilter
+    pagination_class = LimitOffsetPagination
 
     lookup_field = "version"
 
diff --git a/pulp_ansible/app/galaxy/views.py b/pulp_ansible/app/galaxy/views.py
index 69b49d035..5ebbe40dc 100644
--- a/pulp_ansible/app/galaxy/views.py
+++ b/pulp_ansible/app/galaxy/views.py
@@ -167,6 +167,7 @@ class GalaxyCollectionVersionList(generics.ListAPIView):
 
     model = CollectionVersion
     serializer_class = GalaxyCollectionVersionSerializer
+    pagination_class = pagination.PageNumberPagination
     authentication_classes = []
     permission_classes = []
 
diff --git a/pulp_ansible/tests/functional/api/collection/v3/test_collection.py b/pulp_ansible/tests/functional/api/collection/v3/test_collection.py
index 028dfe48f..1536a358d 100644
--- a/pulp_ansible/tests/functional/api/collection/v3/test_collection.py
+++ b/pulp_ansible/tests/functional/api/collection/v3/test_collection.py
@@ -185,8 +185,8 @@ def test_collection_version_list(artifact, pulp_client, collection_detail):
     """Test the versions endpoint, listing the available versions of a given collection."""
     # Version List Endpoint
     versions = pulp_client.using_handler(api.json_handler).get(collection_detail["versions_url"])
-    assert versions["count"] == 1
-    version = versions["results"][0]
+    assert versions["meta"]["count"] == 1
+    version = versions["data"][0]
 
     assert version["version"] == "1.0.0"
     assert version["certification"] == "needs_review"