add desk members api to fetch users for specific desk

SDBELGA-894

apps/desks.py

@@ -27,7 +27,6 @@
 from superdesk.activity import add_activity, ACTIVITY_UPDATE
 from superdesk.metadata.item import FAMILY_ID, ITEM_STATE, CONTENT_STATE
 from eve.utils import ParsedRequest
-from superdesk.utils import ListCursor
 from flask_babel import _, lazy_gettext
 
 
@@ -103,6 +102,9 @@ def init_app(app) -> None:
     endpoint_name = "desk_overview"
     service = OverviewService(endpoint_name, backend=superdesk.get_backend())
     OverviewResource(endpoint_name, app=app, service=service)
+    endpoint_name = "desk_users"
+    service = DeskUsersService(endpoint_name, backend=superdesk.get_backend())
+    DeskUsersResource(endpoint_name, app=app, service=service)
 
 
 superdesk.privilege(
@@ -371,6 +373,42 @@ def get_by_user(self, user_id):
         return list(self.get(req=None, lookup={"user_id": user_id}))
 
 
+class DeskUsersResource(Resource):
+    url = 'desks/<regex("[a-f0-9]{24}"):desk_id>/users'
+    resource_title = "desk_users"
+    datasource = {
+        "source": "users",
+        "default_sort": [("username", 1)],
+        "projection": {
+            "username": 1,
+            "first_name": 1,
+            "last_name": 1,
+            "display_name": 1,
+            "email": 1,
+            "picture_url": 1,
+            "avatar": 1,
+            "avatar_renditions": 1,
+            "role": 1,
+            "last_activity_at": 1,
+            "sign_off": 1,
+        },
+    }
+    resource_methods = ["GET"]
+
+
+class DeskUsersService(BaseService):
+    def get(self, req, lookup):
+        desk_id = lookup.pop("desk_id", None)
+        desks_service = superdesk.get_resource_service("desks")
+        if desk_id:
+            desk = desks_service.find_one(req=None, _id=ObjectId(desk_id))
+            if desk and desk.get("members"):
+                lookup["_id"] = {"$in": [member["user"] for member in desk.get("members", [])]}
+            else:
+                lookup["_id"] = ""  # return empty result
+        return super().get(req, lookup)
+
+
 class SluglineDesksResource(Resource):
     url = 'desks/<regex("[a-f0-9]{24}"):desk_id>/sluglines'
     datasource = {

features/desks.feature

@@ -788,4 +788,25 @@ Feature: Desks
             "template_desks": ["#desks._id#"]
         }
         """
-
+
+    @auth
+    Scenario: Desk members resource
+        Given "users"
+        """
+        [
+            {"username": "foo", "email": "[email protected]", "display_name": "foo"},
+            {"username": "bar", "email": "[email protected]", "display_name": "bar"}
+        ]
+        """
+        And "desks"
+        """
+        [
+            {"name": "Finance", "members": []},
+            {"name": "Sports", "members": [{"user": "#users._id#"}]}
+        ]
+        """
+        When we get "/desks/#desks._id#/users"
+        Then we get list with 1 items
+        """
+        {"_items": [{"username": "bar", "display_name": "bar"}]}
+        """