def upvote(self, request, pk=None):
        obj = self.get_object()
        self.check_permissions(request, "upvote", obj)
        self.pre_conditions_on_save(obj)

        services.add_vote(obj, user=request.user)
        return response.Ok()

    def upvote(self, request, pk=None):
        issue = get_object_or_404(models.Issue, pk=pk)

        self.check_permissions(request, 'upvote', issue)

        votes_service.add_vote(issue, user=request.user)
        return response.Ok()

def test_add_vote():
    project = f.ProjectFactory()
    project_type = ContentType.objects.get_for_model(project)
    user = f.UserFactory()
    votes_qs = models.Votes.objects.filter(content_type=project_type, object_id=project.id)

    votes.add_vote(project, user)

    assert votes_qs.get().count == 1

    votes.add_vote(project, user)  # add_vote must be idempotent

    assert votes_qs.get().count == 1

def test_user_story_voters_retrieve(client, data):
    add_vote(data.public_user_story, data.project_owner)
    public_url = reverse('userstory-voters-detail', kwargs={"resource_id": data.public_user_story.pk,
                                                            "pk": data.project_owner.pk})
    add_vote(data.private_user_story1, data.project_owner)
    private_url1 = reverse('userstory-voters-detail', kwargs={"resource_id": data.private_user_story1.pk,
                                                              "pk": data.project_owner.pk})
    add_vote(data.private_user_story2, data.project_owner)
    private_url2 = reverse('userstory-voters-detail', kwargs={"resource_id": data.private_user_story2.pk,
                                                              "pk": data.project_owner.pk})

    add_vote(data.blocked_user_story, data.project_owner)
    blocked_url = reverse('userstory-voters-detail', kwargs={"resource_id": data.blocked_user_story.pk,
                                                              "pk": data.project_owner.pk})
    users = [
        None,
        data.registered_user,
        data.project_member_without_perms,
        data.project_member_with_perms,
        data.project_owner
    ]

    results = helper_test_http_method(client, 'get', public_url, None, users)
    assert results == [200, 200, 200, 200, 200]
    results = helper_test_http_method(client, 'get', private_url1, None, users)
    assert results == [200, 200, 200, 200, 200]
    results = helper_test_http_method(client, 'get', private_url2, None, users)
    assert results == [401, 403, 403, 200, 200]
    results = helper_test_http_method(client, 'get', blocked_url, None, users)
    assert results == [401, 403, 403, 200, 200]

def test_issue_voters_retrieve(client, data):
    add_vote(data.public_issue, data.project_owner)
    public_url = reverse('issue-voters-detail', kwargs={"issue_id": data.public_issue.pk, "pk": data.project_owner.pk})
    add_vote(data.private_issue1, data.project_owner)
    private_url1 = reverse('issue-voters-detail', kwargs={"issue_id": data.private_issue1.pk, "pk": data.project_owner.pk})
    add_vote(data.private_issue2, data.project_owner)
    private_url2 = reverse('issue-voters-detail', kwargs={"issue_id": data.private_issue2.pk, "pk": data.project_owner.pk})

    users = [
        None,
        data.registered_user,
        data.project_member_without_perms,
        data.project_member_with_perms,
        data.project_owner
    ]

    results = helper_test_http_method(client, 'get', public_url, None, users)
    assert results == [200, 200, 200, 200, 200]

    results = helper_test_http_method(client, 'get', private_url1, None, users)
    assert results == [200, 200, 200, 200, 200]

    results = helper_test_http_method(client, 'get', private_url2, None, users)
    assert results == [401, 403, 403, 200, 200]

 def create_votes(self, obj):
     for i in range(self.sd.int(*NUM_VOTES)):
         user=self.sd.db_object_from_queryset(User.objects.all())
         add_vote(obj, user)

 def create_votes(self, obj, project):
     for i in range(self.sd.int(*NUM_VOTES)):
         voting_user=self.sd.db_object_from_queryset(project.members.all())
         add_vote(obj, voting_user)

    def _add_voter(self, permission, request, pk=None):
        obj = self.get_object()
        self.check_permissions(request, permission, obj)

        services.add_vote(obj, user=request.user)
        return response.Ok()

 def upvote(self, request, pk=None):
     issue = self.get_object()
     votes_service.add_vote(issue, user=request.user)
     return Response(status=status.HTTP_200_OK)