Initial commit

backend/snippets/permissions.py

@@ -0,0 +1,26 @@
+from rest_framework import permissions
+from snippets.models import SnippetParticipant
+
+
+class IsOwnerOrReadOnly(permissions.BasePermission):
+    """
+    Custom permission to only allow owners of an object to edit it.
+    """
+
+    def has_object_permission(self, request, view, obj):
+        # Read permissions are allowed to any request,
+        # so we'll always allow GET, HEAD or OPTIONS requests.
+        if request.method in permissions.SAFE_METHODS:
+            return True
+
+        # Write permissions are only allowed to the owner of the snippet.
+        return obj.owner == request.user
+
+
+class IsAccessedOrDeny(permissions.BasePermission):
+
+    def has_object_permission(self, request, view, obj):
+        if obj.owner == request.user:
+            return True
+        allowed_users = SnippetParticipant.objects.filter(snippet=obj)
+        return request.user in [i.user for i in allowed_users]