Adding leave project API

taiga/projects/api.py

@@ -154,6 +154,13 @@ class ProjectViewSet(ModelCrudViewSet):
         template.save()
         return Response(serializers.ProjectTemplateSerializer(template).data, status=201)
 
+    @detail_route(methods=['post'])
+    def leave(self, request, pk=None):
+        project = self.get_object()
+        self.check_permissions(request, 'leave', project)
+        services.remove_member(project, user=request.user)
+        return Response(status=status.HTTP_200_OK)
+
     def pre_save(self, obj):
         if not obj.id:
             obj.owner = self.request.user

taiga/projects/permissions.py

@@ -13,10 +13,35 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+from django.utils.translation import ugettext_lazy as _
 
 from taiga.base.api.permissions import (TaigaResourcePermission, HasProjectPerm,
                                         IsAuthenticated, IsProjectOwner,
-                                        AllowAny, IsSuperUser)
+                                        AllowAny, IsSuperUser, PermissionComponent)
+
+from taiga.base import exceptions as exc
+from taiga.projects.models import Membership
+
+
+class CanLeaveProject(PermissionComponent):
+    def check_permissions(self, request, view, obj=None):
+        if not obj or not request.user.is_authenticated():
+            return False
+
+        try:
+            membership = Membership.objects.get(user=request.user, project=obj)
+            other_admin_memberships_count = Membership.objects\
+                .exclude(id=membership.id)\
+                .filter(project=obj, is_owner=True)\
+                .count()
+
+            # The project need at least one owner
+            if membership.is_owner and other_admin_memberships_count == 0:
+                raise exc.PermissionDenied(_("You can't leave the project if there are no more owners"))
+
+            return True
+        except Membership.DoesNotExist:
+            return False
 
 
 class ProjectPermission(TaigaResourcePermission):
@@ -37,6 +62,7 @@ class ProjectPermission(TaigaResourcePermission):
     tags_colors_perms = HasProjectPerm('view_project')
     fans_perms = HasProjectPerm('view_project')
     create_template_perms = IsSuperUser()
+    leave_perms = CanLeaveProject()
 
 
 class MembershipPermission(TaigaResourcePermission):

taiga/projects/services/__init__.py

@@ -34,6 +34,7 @@ from .stats import get_member_stats_for_project
 
 from .members import create_members_in_bulk
 from .members import get_members_from_bulk
+from .members import remove_member
 
 from .invitations import send_invitation
 from .invitations import find_invited_user

taiga/projects/services/members.py

@@ -2,7 +2,6 @@ from taiga.base.utils import db, text
 
 from .. import models
 
-
 def get_members_from_bulk(bulk_data, **additional_fields):
     """Convert `bulk_data` into a list of members.
 
@@ -31,3 +30,7 @@ def create_members_in_bulk(bulk_data, callback=None, precall=None, **additional_
     members = get_members_from_bulk(bulk_data, **additional_fields)
     db.save_in_bulk(members, callback, precall)
     return members
+
+
+def remove_member(project, user):
+    models.Membership.objects.get(project=project, user=user).delete()

tests/integration/test_projects.py

@@ -160,3 +160,35 @@ def test_get_closed_bugs_per_member_stats():
 
     assert stats["closed_tasks"][membership_1.user.id] == 1
     assert stats["closed_tasks"][membership_2.user.id] == 0
+
+
+def test_leave_project_valid_membership(client):
+    user = f.UserFactory.create()
+    project = f.ProjectFactory.create()
+    role = f.RoleFactory.create(project=project, permissions=["view_project"])
+    f.MembershipFactory.create(project=project, user=user, role=role)
+    client.login(user)
+    url = reverse("projects-leave", args=(project.id,))
+    response = client.post(url)
+    assert response.status_code == 200
+
+
+def test_leave_project_valid_membership_only_owner(client):
+    user = f.UserFactory.create()
+    project = f.ProjectFactory.create()
+    role = f.RoleFactory.create(project=project, permissions=["view_project"])
+    f.MembershipFactory.create(project=project, user=user, role=role, is_owner=True)
+    client.login(user)
+    url = reverse("projects-leave", args=(project.id,))
+    response = client.post(url)
+    assert response.status_code == 403
+    assert json.loads(response.content)["_error_message"] == "You can't leave the project if there are no more owners"
+
+
+def test_leave_project_invalid_membership(client):
+    user = f.UserFactory.create()
+    project = f.ProjectFactory()
+    client.login(user)
+    url = reverse("projects-leave", args=(project.id,))
+    response = client.post(url)
+    assert response.status_code == 404