Added config for more verbose errors on reset password

- Added settings.py docs
- Fixed left-overs from #4920
- Reworked all server messages to a new argument formet, so that the
client can translate server messages

README.rst

@@ -115,8 +115,17 @@ Download the latest portable version of OpenSlides for Windows from
 install steps. Simply unzip the downloaded file and run ``openslides.exe``.
 
 
+Configuration
+=============
+
+Please consider reading the `OpenSlides configuration
+<https://github.com/OpenSlides/OpenSlides/blob/master/SETTINGS.rst>`_ page to
+find out about all configurations, especially when using OpenSlides for big
+assemblies.
+
+
 Using the Dockerfile
-===============================
+====================
 
 You can either pull the image ``openslides/openslides`` or build it yourself
 (via `docker build -t openslides/openslides .`). You have all prequistes installed

SETTINGS.rst

@@ -0,0 +1,122 @@
+==========================
+ OpenSlides configuration
+==========================
+
+First, locate your `settings.py`. Since this is a regular python file,
+experienced users can also write more advanced configurations with e.g. swithing
+between two sets of configs. This also means, that the syntax need to be correct
+for OpenSlides to start.
+
+All presented settings must be written `<SETTINGS_NAME> = <value>` to follow the
+correct syntax.
+
+The `settings.py` is just an extension for Django settings. Please visit the
+`Django settings documentation
+<https://docs.djangoproject.com/en/2.2/ref/settings/>`_ to get an overview about
+all existing settings.
+
+SECURITY
+========
+
+For `DEBUG` and `SECRET_KEY` see the sections in the django settings
+documenataion.
+
+`RESET_PASSWORD_VERBOSE_ERRORS`: Default: `True`. Set to `False` to disable.
+Controls the verbosity on errors during a reset password. If enabled, an error
+will be shown, if there does not exist a user with a given email address. So one
+can check, if a email is registered. If this is not wanted, disable verbose
+messages. An success message will always be shown.
+
+`AUTH_PASSWORD_VALIDATORS`: Add custom password validators, e.g. a min-length
+validator. See `django auth docs
+<https://docs.djangoproject.com/en/2.2/topics/auth/passwords/#module-django.contrib.auth.password_validation>`_
+for mor information.
+
+Directories
+===========
+
+`OPENSLIDES_USER_DATA_DIR`: The path, where all user data is saved, like static
+files, mediafiles and the default database. This path can be different to the
+location of the `settings.py`.
+
+`STATICFILES_DIRS` and `STATIC_ROOT`: Managing static files. Because the clint
+is not delivered by the server anymore, these settings are obsolete.
+
+`MEDIA_ROOT`: The location of mediafiles. The default is a `media` folder inside
+`OPENSLIDES_USER_DATA_DIR`, but can be altered to another path.
+
+Email
+=====
+
+Please refer to the Django settings documentation. A changed email backend is
+useful for debugging to print all email the the console::
+
+   EMAIL_BACKEND = 'django.core.mail.backends.console.EmailBackend'
+
+
+Logging
+=======
+
+To setup basic logging see `logging
+<https://docs.djangoproject.com/en/2.2/topics/logging/>`_. 
+We recommend to enable all OpenSlides related logging with level `INFO` per
+default::
+
+    LOGGING = {
+        'formatters':
+           'lessnoise': {
+               'format': '[{levelname}] {name} {message}',
+               'style': '{',
+               'datefmt': '[%Y-%m-%d %H:%M:%S %z]',
+           },
+       },
+       'handlers': {
+           'console': {
+               'class': 'logging.StreamHandler',
+               'formatter': 'lessnoise',
+           },
+       },
+       'loggers': {
+           'openslides': {
+               'handlers': ['console'],
+               'level': os.getenv('OPENSLIDES_LOG_LEVEL', 'INFO'),
+           },
+       },
+    }
+
+With the environment variable `OPENSLIDES_LOG_LEVEL` the level can be adjusted
+without changing the `settings.py`.
+
+Big mode and caching
+====================
+
+When running multiple workers redis is required as a message broker between the
+workers. Set `use_redis = True` to enable redis and visit `OpenSLides in big
+mode
+<https://github.com/OpenSlides/OpenSlides/blob/master/DEVELOPMENT.rst#openslides-in-big-mode>`_.
+
+When seting `use_redis = True`, three settings are important:
+
+- Caching: `REDIS_ADDRESS` is used to provide caching with redis across all
+  workers.
+- Channels: The "message queue" for the workers. Adjust the `hosts`-part to the
+  redis address.
+- Sessions: All sessions are managed in redis to ensure them across all workers.
+  Please adjust the `SESSION_REDIS` fields to point to the redis instance.
+
+
+Advanced
+========
+
+`PING_INTERVAL` and `PING_TIMEOUT` are settings for the clients how frequently
+to ping the server (interval) and how big is the timeout. If a ping took longer
+than the timeout, the clients does a forced reconnect.
+
+`COMPRESSION`: Enable or disables the compression when sending data. This does
+not affect the client.
+
+`PRIORITIZED_GROUP_IDS`: A list of group ids. If one client is logged in and the
+operator is in one of these groups, the client disconnected and reconnects again.
+All requests urls (including websockets) are now prefixed with `/prioritize`, so
+these requests from "prioritized clients" can be routed to different servers.
+

client/src/app/core/core-services/http.service.ts

@@ -17,6 +17,20 @@ export enum HTTPMethod {
     DELETE = 'delete'
 }
 
+export interface DetailResponse {
+    detail: string | string[];
+    args?: string[];
+}
+
+function isDetailResponse(obj: any): obj is DetailResponse {
+    return (
+        obj &&
+        typeof obj === 'object' &&
+        (typeof obj.detail === 'string' || obj.detail instanceof Array) &&
+        (!obj.args || obj.args instanceof Array)
+    );
+}
+
 /**
  * Service for managing HTTP requests. Allows to send data for every method. Also (TODO) will do generic error handling.
  */
@@ -128,13 +142,13 @@ export class HttpService {
         } else if (!e.error) {
             error += this.translate.instant("The server didn't respond.");
         } else if (typeof e.error === 'object') {
-            if (e.error.detail) {
+            if (isDetailResponse(e.error)) {
-                error += this.translate.instant(this.processErrorTexts(e.error.detail));
+                error += this.processDetailResponse(e.error);
             } else {
                 error = Object.keys(e.error)
                     .map(key => {
                         const capitalizedKey = key.charAt(0).toUpperCase() + key.slice(1);
-                        return this.translate.instant(capitalizedKey) + ': ' + this.processErrorTexts(e.error[key]);
+                        return this.translate.instant(capitalizedKey) + ': ' + this.processDetailResponse(e.error[key]);
                     })
                     .join(', ');
             }
@@ -155,12 +169,21 @@ export class HttpService {
      * @param str a string or a string array to join together.
      * @returns Error text(s) as single string
      */
-    private processErrorTexts(str: string | string[]): string {
+    private processDetailResponse(response: DetailResponse): string {
-        if (str instanceof Array) {
+        let message: string;
-            return str.join(' ');
+        if (response.detail instanceof Array) {
+            message = response.detail.join(' ');
         } else {
-            return str;
+            message = response.detail;
         }
+        message = this.translate.instant(message);
+
+        if (response.args && response.args.length > 0) {
+            for (let i = 0; i < response.args.length; i++) {
+                message = message.replace(`{${i}}`, response.args[i].toString());
+            }
+        }
+        return message;
     }
 
     /**

openslides/agenda/signals.py

@@ -64,7 +64,8 @@ def listen_to_related_object_post_save(sender, instance, created, **kwargs):
                     except Item.DoesNotExist:
                         raise ValidationError(
                             {
-                                "detail": f"The parent item with id {parent_id} does not exist"
+                                "detail": "The parent item with id {0} does not exist",
+                                "args": [parent_id],
                             }
                         )
                     attrs["weight"] = parent.weight + 1

openslides/agenda/views.py

@@ -86,7 +86,7 @@ class ItemViewSet(ModelViewSet, TreeSortMixin):
         try:
             model = get_model_from_collection_string(collection)
         except ValueError:
-            raise ValidationError("Invalid collection")
+            raise ValidationError({"detail": "Invalid collection"})
 
         try:
             content_object = model.objects.get(pk=id)
@@ -220,7 +220,10 @@ class ItemViewSet(ModelViewSet, TreeSortMixin):
             parent = Item.objects.get(pk=request.data["parent_id"])
         except Item.DoesNotExist:
             raise ValidationError(
-                {"detail": f"Parent item {request.data['parent_id']} does not exist"}
+                {
+                    "detail": "Parent item {0} does not exist",
+                    "args": [request.data["parent_id"]],
+                }
             )
 
         # Collect ancestors
@@ -237,7 +240,8 @@ class ItemViewSet(ModelViewSet, TreeSortMixin):
             if item_id in ancestors:
                 raise ValidationError(
                     {
-                        "detail": f"Assigning item {item_id} to one of its children is not possible."
+                        "detail": "Assigning item {0} to one of its children is not possible.",
+                        "args": [item_id],
                     }
                 )
 
@@ -245,7 +249,9 @@ class ItemViewSet(ModelViewSet, TreeSortMixin):
             try:
                 items.append(Item.objects.get(pk=item_id))
             except Item.DoesNotExist:
-                raise ValidationError({"detail": f"Item {item_id} does not exist"})
+                raise ValidationError(
+                    {"detail": "Item {0} does not exist", "args": [item_id]}
+                )
 
         # OK, assign new parents.
         for item in items:
@@ -257,7 +263,9 @@ class ItemViewSet(ModelViewSet, TreeSortMixin):
         inform_changed_data(items)
 
         # Send response.
-        return Response({"detail": f"{len(items)} items successfully assigned."})
+        return Response(
+            {"detail": "{0} items successfully assigned.", "args": [len(items)]}
+        )
 
 
 class ListOfSpeakersViewSet(
@@ -464,7 +472,8 @@ class ListOfSpeakersViewSet(
             except Speaker.DoesNotExist:
                 raise ValidationError(
                     {
-                        "detail": f"There is no one speaking at the moment according to {list_of_speakers}."
+                        "detail": "There is no one speaking at the moment according to {0}.",
+                        "args": [list_of_speakers],
                     }
                 )
             current_speaker.end_speech()

openslides/assignments/serializers.py

@@ -147,20 +147,25 @@ class AssignmentAllPollSerializer(ModelSerializer):
             if len(votes) != len(options):
                 raise ValidationError(
                     {
-                        "detail": f"You have to submit data for {len(options)} candidates."
+                        "detail": "You have to submit data for {0} candidates.",
+                        "args": [len(options)],
                     }
                 )
             for index, option in enumerate(options):
                 if len(votes[index]) != len(instance.get_vote_values()):
                     raise ValidationError(
                         {
-                            "detail": f"You have to submit data for {len(instance.get_vote_values())} vote values."
+                            "detail": "You have to submit data for {0} vote values",
+                            "args": [len(instance.get_vote_values())],
                         }
                     )
                 for vote_value, __ in votes[index].items():
                     if vote_value not in instance.get_vote_values():
                         raise ValidationError(
-                            {"detail": f"Vote value {vote_value} is invalid."}
+                            {
+                                "detail": "Vote value {0} is invalid.",
+                                "args": [vote_value],
+                            }
                         )
                 instance.set_vote_objects_with_values(
                     option, votes[index], skip_autoupdate=True

openslides/assignments/views.py

@@ -131,8 +131,12 @@ class AssignmentViewSet(ModelViewSet):
         self.mark_elected can play with it.
         """
         if not isinstance(request.data, dict):
-            detail = f"Invalid data. Expected dictionary, got {type(request.data)}."
+            raise ValidationError(
-            raise ValidationError({"detail": detail})
+                {
+                    "detail": "Invalid data. Expected dictionary, got {0}.",
+                    "args": [type(request.data)],
+                }
+            )
         user_str = request.data.get("user", "")
         try:
             user_pk = int(user_str)
@@ -144,7 +148,7 @@ class AssignmentViewSet(ModelViewSet):
             user = get_user_model().objects.get(pk=user_pk)
         except get_user_model().DoesNotExist:
             raise ValidationError(
-                {"detail": f"Invalid data. User {user_pk} does not exist."}
+                {"detail": "Invalid data. User {0} does not exist.", "args": [user_pk]}
             )
         return user
 
@@ -157,46 +161,60 @@ class AssignmentViewSet(ModelViewSet):
         user = self.get_user_from_request_data(request)
         assignment = self.get_object()
         if request.method == "POST":
-            message = self.nominate_other(request, user, assignment)
+            return self.nominate_other(request, user, assignment)
         else:
             # request.method == 'DELETE'
-            message = self.delete_other(request, user, assignment)
+            return self.delete_other(request, user, assignment)
-        return Response({"detail": message})
 
     def nominate_other(self, request, user, assignment):
         if assignment.is_elected(user):
-            raise ValidationError({"detail": f"User {user} is already elected."})
+            raise ValidationError(
-        if assignment.phase == assignment.PHASE_FINISHED:
+                {"detail": "User {0} is already elected.", "args": [str(user)]}
-            detail = (
+            )
-                "You can not nominate someone to this election because it is finished."
+        if assignment.phase == assignment.PHASE_FINISHED:
+            raise ValidationError(
+                {
+                    "detail": "You can not nominate someone to this election because it is finished."
+                }
             )
-            raise ValidationError({"detail": detail})
         if assignment.phase == assignment.PHASE_VOTING and not has_perm(
             request.user, "assignments.can_manage"
         ):
             # To nominate another user during voting you have to be a manager.
             self.permission_denied(request)
         if assignment.is_candidate(user):
-            raise ValidationError({"detail": f"User {user} is already nominated."})
+            raise ValidationError(
+                {"detail": "User {0} is already nominated.", "args": [str(user)]}
+            )
         assignment.set_candidate(user)
         # Send new candidate via autoupdate because users without permission
         # to see users may not have it but can get it now.
         inform_changed_data(user)
-        return f"User {user} was nominated successfully."
+        return Response(
+            {"detail": "User {0} was nominated successfully.", "args": [str(user)]}
+        )
 
     def delete_other(self, request, user, assignment):
         # To delete candidature status you have to be a manager.
         if not has_perm(request.user, "assignments.can_manage"):
             self.permission_denied(request)
         if assignment.phase == assignment.PHASE_FINISHED:
-            detail = "You can not delete someone's candidature to this election because it is finished."
+            raise ValidationError(
-            raise ValidationError({"detail": detail})
+                {
+                    "detail": "You can not delete someone's candidature to this election because it is finished."
+                }
+            )
         if not assignment.is_candidate(user) and not assignment.is_elected(user):
             raise ValidationError(
-                {"detail": f"User {user} has no status in this election."}
+                {
+                    "detail": "User {0} has no status in this election.",
+                    "args": [str(user)],
+                }
             )
         assignment.delete_related_user(user)
-        return f"Candidate {user} was withdrawn successfully."
+        return Response(
+            {"detail": "Candidate {0} was withdrawn successfully.", "args": [str(user)]}
+        )
 
     @detail_route(methods=["post", "delete"])
     def mark_elected(self, request, pk=None):
@@ -209,18 +227,25 @@ class AssignmentViewSet(ModelViewSet):
         if request.method == "POST":
             if not assignment.is_candidate(user):
                 raise ValidationError(
-                    {"detail": f"User {user} is not a candidate of this election."}
+                    {
+                        "detail": "User {0} is not a candidate of this election.",
+                        "args": [str(user)],
+                    }
                 )
             assignment.set_elected(user)
-            message = f"User {user} was successfully elected."
+            message = "User {0} was successfully elected."
         else:
             # request.method == 'DELETE'
             if not assignment.is_elected(user):
-                detail = f"User {user} is not an elected candidate of this election."
+                raise ValidationError(
-                raise ValidationError({"detail": detail})
+                    {
+                        "detail": "User {0} is not an elected candidate of this election.",
+                        "args": [str(user)],
+                    }
+                )
             assignment.set_candidate(user)
-            message = f"User {user} was successfully unelected."
+            message = "User {0} was successfully unelected."
-        return Response({"detail": message})
+        return Response({"detail": message, "args": [str(user)]})
 
     @detail_route(methods=["post"])
     def create_poll(self, request, pk=None):

openslides/core/serializers.py

@@ -62,7 +62,7 @@ def elements_validator(value: Any) -> None:
             )
         if element["name"] not in projector_slides:
             raise ValidationError(
-                {"detail": f"Unknown projector element {element['name']},"}
+                {"detail": "Unknown projector element {0}.", "args": [element["name"]]}
             )
 
 

openslides/core/views.py

@@ -291,8 +291,9 @@ class ProjectorViewSet(ModelViewSet):
         projector_instance.scroll = request.data
 
         projector_instance.save()
-        message = f"Setting scroll to {request.data} was successful."
+        return Response(
-        return Response({"detail": message})
+            {"detail": "Setting scroll to {0} was successful.", "args": [request.data]}
+        )
 
 
 class ProjectionDefaultViewSet(ListModelMixin, RetrieveModelMixin, GenericViewSet):

openslides/mediafiles/views.py

@@ -126,7 +126,7 @@ class MediafileViewSet(ModelViewSet):
                 mediafiles.append(Mediafile.objects.get(pk=id))
             except Mediafile.DoesNotExist:
                 raise ValidationError(
-                    {"detail": f"The mediafile with id {id} does not exist"}
+                    {"detail": "The mediafile with id {0} does not exist", "args": [id]}
                 )
 
         # Search for valid parents (None is not included, but also safe!)
@@ -181,7 +181,7 @@ class MediafileViewSet(ModelViewSet):
                 mediafiles.append(Mediafile.objects.get(pk=id))
             except Mediafile.DoesNotExist:
                 raise ValidationError(
-                    {"detail": f"The mediafile with id {id} does not exist"}
+                    {"detail": "The mediafile with id {0} does not exist", "args": [id]}
                 )
         if not mediafiles:
             return Response()

openslides/motions/models.py

@@ -1,6 +1,5 @@
 from django.conf import settings
 from django.contrib.auth.models import AnonymousUser
-from django.core.exceptions import ImproperlyConfigured, ValidationError
 from django.db import IntegrityError, models, transaction
 from django.db.models import Max
 from jsonfield import JSONField
@@ -18,6 +17,7 @@ from openslides.poll.models import (
 from openslides.utils.autoupdate import inform_changed_data
 from openslides.utils.exceptions import OpenSlidesError
 from openslides.utils.models import RESTModelMixin
+from openslides.utils.rest_api import ValidationError
 
 from ..utils.models import CASCADE_AND_AUTOUPDATE, SET_NULL_AND_AUTOUPDATE
 from .access_permissions import (
@@ -401,17 +401,9 @@ class Motion(RESTModelMixin, AgendaItemWithListOfSpeakersMixin, models.Model):
         Returns the number used in the set_identifier method with leading
         zero charaters according to the config value.
         """
-        result = str(number)
+        return "0" * (config["motions_identifier_min_digits"] - len(str(number))) + str(
-        if config["motions_identifier_min_digits"]:
+            number
-            if not isinstance(config["motions_identifier_min_digits"], int):
-                raise ImproperlyConfigured(
-                    "Config value 'motions_identifier_min_digits' must be an integer."
         )
-            result = (
-                "0" * (config["motions_identifier_min_digits"] - len(str(number)))
-                + result
-            )
-        return result
 
     def is_submitter(self, user):
         """
@@ -766,7 +758,10 @@ class MotionChangeRecommendation(RESTModelMixin, models.Model):
 
         if self.collides_with_other_recommendation(recommendations):
             raise ValidationError(
-                f"The recommendation collides with an existing one (line {self.line_from} - {self.line_to})."
+                {
+                    "detail": "The recommendation collides with an existing one (line {0} - {1}).",
+                    "args": [self.line_from, self.line_to],
+                }
             )
 
         result = super().save(*args, **kwargs)

openslides/motions/numbering.py

@@ -1,7 +1,6 @@
 from collections import defaultdict
 from typing import Any, Dict, List, Tuple
 
-from django.conf import settings
 from django.db import transaction
 from django.db.models import Model
 
@@ -41,11 +40,8 @@ def numbering(main_category: Category) -> List[Model]:
     - Both counters may be filled with leading zeros according to `Motion.extend_identifier_number`
     - On errors, ValidationErrors with appropriate content will be raised.
     """
-    # If MOTION_IDENTIFIER_WITHOUT_BLANKS is set, don't use blanks when building identifier.
+    # If the config is false, don't use blanks when building identifier.
-    without_blank = (
+    without_blank = not config["motions_identifier_with_blank"]
-        hasattr(settings, "MOTION_IDENTIFIER_WITHOUT_BLANKS")
-        and settings.MOTION_IDENTIFIER_WITHOUT_BLANKS
-    )
 
     # Get child categories (to build affected categories) and precalculate all prefixes.
     child_categories = get_child_categories(main_category)
@@ -171,9 +167,10 @@ def get_amendment_level_mapping(
         if motion.parent_id is not None and motion.parent_id not in affected_motion_ids:
             raise ValidationError(
                 {
-                    "detail": f'Amendment "{motion}" cannot be numbered, because '
+                    "detail": 'Amendment "{0}" cannot be numbered, because '
-                    f"it's lead motion ({motion.parent}) is not in category "
+                    "it's lead motion ({1}) is not in category "
-                    f"{main_category} or any subcategory."
+                    "{2} or any subcategory.",
+                    "args": [str(motion), str(motion.parent), str(main_category)],
                 }
             )
     return max_amendment_level, amendment_level_mapping
@@ -234,17 +231,22 @@ def check_new_identifiers_for_conflicts(
         # We do have a conflict. Build a nice error message.
         conflicting_motion = conflicting_motions.first()
         if conflicting_motion.category:
-            error_message = (
+            raise ValidationError(
-                "Numbering aborted because the motion identifier "
+                {
-                f'"{conflicting_motion.identifier}" already exists in '
+                    "detail": 'Numbering aborted because the motion identifier "{0}" already exists in category {1}.',
-                f"category {conflicting_motion.category}."
+                    "args": [
+                        conflicting_motion.identifier,
+                        str(conflicting_motion.category),
+                    ],
+                }
             )
         else:
-            error_message = (
+            raise ValidationError(
-                "Numbering aborted because the motion identifier "
+                {
-                f'"{conflicting_motion.identifier}" already exists.'
+                    "detail": 'Numbering aborted because the motion identifier "{0}" already exists.',
+                    "args": [conflicting_motion.identifier],
+                }
             )
-        raise ValidationError({"detail": error_message})
 
 
 def update_identifiers(affected_motions, new_identifier_mapping) -> List[Model]:

openslides/motions/serializers.py

@@ -41,7 +41,9 @@ def validate_workflow_field(value):
     Validator to ensure that the workflow with the given id exists.
     """
     if not Workflow.objects.filter(pk=value).exists():
-        raise ValidationError({"detail": f"Workflow {value} does not exist."})
+        raise ValidationError(
+            {"detail": "Workflow {0} does not exist.", "args": [value]}
+        )
 
 
 class StatuteParagraphSerializer(ModelSerializer):
@@ -307,13 +309,14 @@ class MotionPollSerializer(ModelSerializer):
             if len(votes) != len(instance.get_vote_values()):
                 raise ValidationError(
                     {
-                        "detail": f"You have to submit data for {len(instance.get_vote_values())} vote values."
+                        "detail": "You have to submit data for {0} vote values.",
+                        "args": [len(instance.get_vote_values())],
                     }
                 )
             for vote_value in votes.keys():
                 if vote_value not in instance.get_vote_values():
                     raise ValidationError(
-                        {"detail": f"Vote value {vote_value} is invalid."}
+                        {"detail": "Vote value {0} is invalid.", "args": [vote_value]}
                     )
             instance.set_vote_objects_with_values(
                 instance.get_options().get(), votes, skip_autoupdate=True

openslides/motions/views.py

@@ -2,7 +2,6 @@ from typing import List, Set
 
 import jsonschema
 from django.contrib.auth import get_user_model
-from django.core.exceptions import ValidationError as DjangoValidationError
 from django.db import transaction
 from django.db.models import Case, When
 from django.db.models.deletion import ProtectedError
@@ -358,7 +357,10 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
             section = MotionCommentSection.objects.get(pk=section_id)
         except MotionCommentSection.DoesNotExist:
             raise ValidationError(
-                {"detail": f"A comment section with id {section_id} does not exist."}
+                {
+                    "detail": "A comment section with id {0} does not exist.",
+                    "args": [section_id],
+                }
             )
 
         # the request user needs to see and write to the comment section
@@ -448,7 +450,9 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
             try:
                 motion = Motion.objects.get(pk=item["id"])
             except Motion.DoesNotExist:
-                raise ValidationError({"detail": f"Motion {item['id']} does not exist"})
+                raise ValidationError(
+                    {"detail": "Motion {0} does not exist", "args": [item["id"]]}
+                )
 
             # Remove all submitters.
             Submitter.objects.filter(motion=motion).delete()
@@ -459,7 +463,10 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
                     submitter = get_user_model().objects.get(pk=submitter_id)
                 except get_user_model().DoesNotExist:
                     raise ValidationError(
-                        {"detail": f"Submitter {submitter_id} does not exist"}
+                        {
+                            "detail": "Submitter {0} does not exist",
+                            "args": [submitter_id],
+                        }
                     )
                 Submitter.objects.add(submitter, motion)
                 new_submitters.append(submitter)
@@ -479,7 +486,10 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
 
         # Send response.
         return Response(
-            {"detail": f"{len(motion_result)} motions successfully updated."}
+            {
+                "detail": "{0} motions successfully updated.",
+                "args": [len(motion_result)],
+            }
         )
 
     @detail_route(methods=["post", "delete"])
@@ -566,7 +576,9 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
             try:
                 motion = Motion.objects.get(pk=item["id"])
             except Motion.DoesNotExist:
-                raise ValidationError({"detail": f"Motion {item['id']} does not exist"})
+                raise ValidationError(
+                    {"detail": "Motion {0} does not exist", "args": [item["id"]]}
+                )
 
             # Get category
             category = None
@@ -575,7 +587,10 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
                     category = Category.objects.get(pk=item["category"])
                 except Category.DoesNotExist:
                     raise ValidationError(
-                        {"detail": f"Category {item['category']} does not exist"}
+                        {
+                            "detail": "Category {0} does not exist",
+                            "args": [item["category"]],
+                        }
                     )
 
             # Set category
@@ -601,7 +616,10 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
 
         # Send response.
         return Response(
-            {"detail": f"Category of {len(motion_result)} motions successfully set."}
+            {
+                "detail": "Category of {0} motions successfully set.",
+                "args": [len(motion_result)],
+            }
         )
 
     @list_route(methods=["post"])
@@ -645,7 +663,9 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
             try:
                 motion = Motion.objects.get(pk=item["id"])
             except Motion.DoesNotExist:
-                raise ValidationError({"detail": f"Motion {item['id']} does not exist"})
+                raise ValidationError(
+                    {"detail": "Motion {0} does not exist", "args": [item["id"]]}
+                )
 
             # Get motion block
             motion_block = None
@@ -654,7 +674,10 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
                     motion_block = MotionBlock.objects.get(pk=item["motion_block"])
                 except MotionBlock.DoesNotExist:
                     raise ValidationError(
-                        {"detail": f"MotionBlock {item['motion_block']} does not exist"}
+                        {
+                            "detail": "MotionBlock {0} does not exist",
+                            "args": [item["motion_block"]],
+                        }
                     )
 
             # Set motion bock
@@ -681,7 +704,8 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
         # Send response.
         return Response(
             {
-                "detail": f"Motion block of {len(motion_result)} motions successfully set."
+                "detail": "Motion block of {0} motions successfully set.",
+                "args": [len(motion_result)],
             }
         )
 
@@ -714,7 +738,7 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
                 )
             if not motion.state.is_next_or_previous_state_id(state_id):
                 raise ValidationError(
-                    {"detail": f"You can not set the state to {state_id}."}
+                    {"detail": "You can not set the state to {0}.", "args": [state_id]}
                 )
             motion.set_state(state_id)
         else:
@@ -786,7 +810,9 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
             try:
                 motion = Motion.objects.get(pk=item["id"])
             except Motion.DoesNotExist:
-                raise ValidationError({"detail": f"Motion {item['id']} does not exist"})
+                raise ValidationError(
+                    {"detail": "Motion {0} does not exist", "args": [item["id"]]}
+                )
 
             # Set or reset state.
             state_id = item["state"]
@@ -794,7 +820,7 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
             if state_id not in [item.id for item in valid_states]:
                 # States of different workflows are not allowed.
                 raise ValidationError(
-                    {"detail": f"You can not set the state to {state_id}."}
+                    {"detail": "You can not set the state to {0}.", "args": [state_id]}
                 )
             motion.set_state(state_id)
 
@@ -826,7 +852,10 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
 
         # Send response.
         return Response(
-            {"detail": f"State of {len(motion_result)} motions successfully set."}
+            {
+                "detail": "State of {0} motions successfully set.",
+                "args": [len(motion_result)],
+            }
         )
 
     @detail_route(methods=["put"])
@@ -858,7 +887,8 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
             ]:
                 raise ValidationError(
                     {
-                        "detail": f"You can not set the recommendation to {recommendation_state_id}."
+                        "detail": "You can not set the recommendation to {0}.",
+                        "args": [recommendation_state_id],
                     }
                 )
             motion.set_recommendation(recommendation_state_id)
@@ -875,7 +905,6 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
             if motion.recommendation
             else "None"
         )
-        message = f"The recommendation of the motion was set to {label}."
 
         # Fire autoupdate again to save information to OpenSlides history.
         inform_changed_data(
@@ -884,7 +913,12 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
             user_id=request.user.pk,
         )
 
-        return Response({"detail": message})
+        return Response(
+            {
+                "detail": "The recommendation of the motion was set to {0}.",
+                "args": [label],
+            }
+        )
 
     @list_route(methods=["post"])
     @transaction.atomic
@@ -927,7 +961,9 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
             try:
                 motion = Motion.objects.get(pk=item["id"])
             except Motion.DoesNotExist:
-                raise ValidationError({"detail": f"Motion {item['id']} does not exist"})
+                raise ValidationError(
+                    {"detail": "Motion {0} does not exist", "args": [item["id"]]}
+                )
 
             # Set or reset recommendation.
             recommendation_state_id = item["recommendation"]
@@ -944,7 +980,8 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
                 ]:
                     raise ValidationError(
                         {
-                            "detail": "You can not set the recommendation to {recommendation_state_id}."
+                            "detail": "You can not set the recommendation to {0}.",
+                            "args": [recommendation_state_id],
                         }
                     )
                 motion.set_recommendation(recommendation_state_id)
@@ -971,7 +1008,10 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
 
         # Send response.
         return Response(
-            {"detail": f"{len(motion_result)} motions successfully updated."}
+            {
+                "detail": "{0} motions successfully updated.",
+                "args": [len(motion_result)],
+            }
         )
 
     @detail_route(methods=["post"])
@@ -1070,12 +1110,16 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
             try:
                 motion = Motion.objects.get(pk=item["id"])
             except Motion.DoesNotExist:
-                raise ValidationError({"detail": f"Motion {item['id']} does not exist"})
+                raise ValidationError(
+                    {"detail": "Motion {0} does not exist", "args": [item["id"]]}
+                )
 
             # Set new tags
             for tag_id in item["tags"]:
                 if not Tag.objects.filter(pk=tag_id).exists():
-                    raise ValidationError({"detail": f"Tag {tag_id} does not exist"})
+                    raise ValidationError(
+                        {"detail": "Tag {0} does not exist", "args": [tag_id]}
+                    )
             motion.tags.set(item["tags"])
 
             # Finish motion.
@@ -1086,7 +1130,10 @@ class MotionViewSet(TreeSortMixin, ModelViewSet):
 
         # Send response.
         return Response(
-            {"detail": f"{len(motion_result)} motions successfully updated."}
+            {
+                "detail": "{0} motions successfully updated.",
+                "args": [len(motion_result)],
+            }
         )
 
 
@@ -1164,15 +1211,6 @@ class MotionChangeRecommendationViewSet(ModelViewSet):
             result = False
         return result
 
-    def create(self, request, *args, **kwargs):
-        """
-        Creating a Change Recommendation, custom exception handling
-        """
-        try:
-            return super().create(request, *args, **kwargs)
-        except DjangoValidationError as err:
-            return Response({"detail": err.message}, status=400)
-
     def perform_create(self, serializer):
         """
         Customized method to add history information.
@@ -1253,12 +1291,12 @@ class MotionCommentSectionViewSet(ModelViewSet):
                 motions_verbose += ", ..."
 
             if count == 1:
-                msg = f"This section has still comments in motion {motions_verbose}."
+                msg = "This section has still comments in motion {0}."
             else:
-                msg = f"This section has still comments in motions {motions_verbose}."
+                msg = "This section has still comments in motions {0}."
 
             msg += " " + "Please remove all comments before deletion."
-            raise ValidationError({"detail": msg})
+            raise ValidationError({"detail": msg, "args": [motions_verbose]})
         return result
 
     def update(self, *args, **kwargs):
@@ -1440,7 +1478,8 @@ class CategoryViewSet(TreeSortMixin, ModelViewSet):
         )
         return Response(
             {
-                "detail": f"All motions in category {main_category} numbered successfully."
+                "detail": "All motions in category {0} numbered successfully.",
+                "args": [str(main_category)],
             }
         )
 
@@ -1503,7 +1542,7 @@ class MotionBlockViewSet(ModelViewSet):
 
 
 class ProtectedErrorMessageMixin:
-    def getProtectedErrorMessage(self, name, error):
+    def raiseProtectedError(self, name, error):
         # The protected objects can just be motions..
         motions = ['"' + str(m) + '"' for m in error.protected_objects.all()]
         count = len(motions)
@@ -1512,10 +1551,15 @@ class ProtectedErrorMessageMixin:
             motions_verbose += ", ..."
 
         if count == 1:
-            msg = f"This {name} is assigned to motion {motions_verbose}."
+            msg = f"This {0} is assigned to motion {1}."
         else:
-            msg = f"This {name} is assigned to motions {motions_verbose}."
+            msg = f"This {0} is assigned to motions {1}."
-        return f"{msg} Please remove all assignments before deletion."
+        raise ValidationError(
+            {
+                "detail": f"{msg} Please remove all assignments before deletion.",
+                "args": [name, motions_verbose],
+            }
+        )
 
 
 class WorkflowViewSet(ModelViewSet, ProtectedErrorMessageMixin):
@@ -1555,8 +1599,7 @@ class WorkflowViewSet(ModelViewSet, ProtectedErrorMessageMixin):
         try:
             result = super().destroy(*args, **kwargs)
         except ProtectedError as err:
-            msg = self.getProtectedErrorMessage("workflow", err)
+            self.raiseProtectedError("workflow", err)
-            raise ValidationError({"detail": msg})
 
         # Change motion default workflows in the config
         if int(config["motions_workflow"]) == workflow_pk:
@@ -1608,8 +1651,7 @@ class StateViewSet(ModelViewSet, ProtectedErrorMessageMixin):
         try:
             result = super().destroy(*args, **kwargs)
         except ProtectedError as err:
-            msg = self.getProtectedErrorMessage("workflow", err)
+            self.raiseProtectedError("workflow", err)
-            raise ValidationError({"detail": msg})
         inform_changed_data(workflow)
         return result
 

openslides/poll/serializers.py

@@ -14,6 +14,6 @@ def default_votes_validator(data):
             and data[key] < -2
         ):
             raise ValidationError(
-                {"detail": f"Value for {key} must not be less than -2"}
+                {"detail": "Value for {0} must not be less than -2", "args": [key]}
             )
     return data

openslides/users/models.py

@@ -227,7 +227,7 @@ class User(RESTModelMixin, PermissionsMixin, AbstractBaseUser):
         try:
             message = message.format(**message_format)
         except KeyError as err:
-            raise ValidationError({"detail": f"Invalid property {err}."})
+            raise ValidationError({"detail": "Invalid property {0}", "args": [err]})
 
         subject_format = format_dict(
             {"event_name": config["general_event_name"], "username": self.username}
@@ -235,7 +235,7 @@ class User(RESTModelMixin, PermissionsMixin, AbstractBaseUser):
         try:
             subject = subject.format(**subject_format)
         except KeyError as err:
-            raise ValidationError({"detail": f"Invalid property {err}."})
+            raise ValidationError({"detail": "Invalid property {0}", "args": [err]})
 
         # Create an email and send it.
         email = mail.EmailMessage(
@@ -255,7 +255,10 @@ class User(RESTModelMixin, PermissionsMixin, AbstractBaseUser):
                 helptext = " Is the email sender correct?"
             connection.close()
             raise ValidationError(
-                {"detail": f"Error {error}. Cannot send email.{helptext}"}
+                {
+                    "detail": "Error {0}. Cannot send email.{1}",
+                    "args": [error, helptext],
+                }
             )
         except smtplib.SMTPRecipientsRefused:
             pass  # Run into returning false later
@@ -263,7 +266,8 @@ class User(RESTModelMixin, PermissionsMixin, AbstractBaseUser):
             # Nice error message on auth failure
             raise ValidationError(
                 {
-                    "detail": f"Error {e.smtp_code}: Authentication failure. Please contact your local administrator."
+                    "detail": "Error {0}: Authentication failure. Please contact your local administrator.",
+                    "args": [e.smtp_code],
                 }
             )
         else:

openslides/users/views.py

@@ -202,7 +202,8 @@ class UserViewSet(ModelViewSet):
                 errors = " ".join(errors)
                 raise ValidationError(
                     {
-                        "detail": f'The default password of user "{user.username}" is not valid: {errors}'
+                        "detail": 'The default password of user "{0}" is not valid: {1}',
+                        "args": [user.username, str(errors)],
                     }
                 )
 
@@ -331,7 +332,8 @@ class UserViewSet(ModelViewSet):
         inform_changed_data(created_users)
         return Response(
             {
-                "detail": f"{len(created_users)} users successfully imported.",
+                "detail": "{0} users successfully imported.",
+                "args": [len(created_users)],
                 "importedTrackIds": imported_track_ids,
             }
         )
@@ -362,7 +364,8 @@ class UserViewSet(ModelViewSet):
         except ConnectionRefusedError:
             raise ValidationError(
                 {
-                    "detail": f"Cannot connect to SMTP server on {settings.EMAIL_HOST}:{settings.EMAIL_PORT}"
+                    "detail": "Cannot connect to SMTP server on {0}:{1}",
+                    "args": [settings.EMAIL_HOST, settings.EMAIL_PORT],
                 }
             )
         except smtplib.SMTPException as err:
@@ -391,7 +394,7 @@ class UserViewSet(ModelViewSet):
     def assert_list_of_ints(self, ids, ids_name="user_ids"):
         """ Asserts, that ids is a list of ints. Raises a ValidationError, if not. """
         if not isinstance(ids, list):
-            raise ValidationError({"detail": f"{ids_name} must be a list"})
+            raise ValidationError({"detail": "{0} must be a list", "args": [ids_name]})
         for id in ids:
             if not isinstance(id, int):
                 raise ValidationError({"detail": "Every id must be a int"})
@@ -546,7 +549,10 @@ class GroupViewSet(ModelViewSet):
         inform_changed_data(group)
 
         return Response(
-            {"detail": f"Permissions of group {group.pk} successfully changed."}
+            {
+                "detail": "Permissions of group {0} successfully changed.",
+                "args": [group.pk],
+            }
         )
 
     def inform_permission_change(
@@ -627,7 +633,8 @@ class PersonalNoteViewSet(ModelViewSet):
         except IntegrityError:
             raise ValidationError(
                 {
-                    "detail": f"The personal note for user {self.request.user.id} does already exist"
+                    "detail": "The personal note for user {0} does already exist",
+                    "args": [self.request.user.id],
                 }
             )
 
@@ -812,7 +819,14 @@ class PasswordResetView(APIView):
         Loop over all users and send emails.
         """
         to_email = request.data.get("email")
-        for user in self.get_users(to_email):
+        users = self.get_users(to_email)
+
+        if len(users) == 0 and getattr(settings, "RESET_PASSWORD_VERBOSE_ERRORS", True):
+            raise ValidationError(
+                {"detail": "No users with email {0} found.", "args": [to_email]}
+            )
+
+        for user in users:
             current_site = get_current_site(request)
             site_name = current_site.name
             if has_perm(user, "users.can_change_password") or has_perm(
@@ -850,14 +864,16 @@ class PasswordResetView(APIView):
             except smtplib.SMTPRecipientsRefused:
                 raise ValidationError(
                     {
-                        "detail": f"Error: The email to {to_email} was refused by the server. Please contact your local administrator."
+                        "detail": "Error: The email to {0} was refused by the server. Please contact your local administrator.",
+                        "args": [to_email],
                     }
                 )
             except smtplib.SMTPAuthenticationError as e:
                 # Nice error message on auth failure
                 raise ValidationError(
                     {
-                        "detail": f"Error {e.smtp_code}: Authentication failure. Please contact your administrator."
+                        "detail": "Error {0}: Authentication failure. Please contact your administrator.",
+                        "args": [e.smtp_code],
                     }
                 )
             except ConnectionRefusedError:
@@ -866,7 +882,7 @@ class PasswordResetView(APIView):
                         "detail": "Connection refused error. Please contact your administrator."
                     }
                 )
-        return super().post(request, *args, **kwargs)
+        return Response()
 
     def get_users(self, email):
         """Given an email, return matching user(s) who should receive a reset.
@@ -878,7 +894,7 @@ class PasswordResetView(APIView):
         active_users = User.objects.filter(
             **{"email__iexact": email, "is_active": True}
         )
-        return (u for u in active_users if u.has_usable_password())
+        return [u for u in active_users if u.has_usable_password()]
 
     def get_email_body(self, **context):
         """

openslides/utils/settings.py.tpl

@@ -2,10 +2,7 @@
 Settings file for OpenSlides.
 
 For more information on this file, see
-https://docs.djangoproject.com/en/1.10/topics/settings/
+https://github.com/OpenSlides/OpenSlides/blob/master/SETTINGS.rst
-
-For the full list of settings and their values, see
-https://docs.djangoproject.com/en/1.10/ref/settings/
 """
 
 import os
@@ -40,6 +37,13 @@ SECRET_KEY = %(secret_key)r
 
 DEBUG = %(debug)s
 
+# Controls the verbosity on errors during a reset password. If enabled, an error
+# will be shown, if there does not exist a user with a given email address. So one
+# can check, if a email is registered. If this is not wanted, disable verbose
+# messages. An success message will always be shown.
+
+RESET_PASSWORD_VERBOSE_ERRORS = True
+
 # Email settings
 # For SSL/TLS specific settings see https://docs.djangoproject.com/en/1.11/topics/email/#smtp-backend
 

openslides/utils/views.py

@@ -59,7 +59,7 @@ class TreeSortMixin:
         does not have every model, the remaining models are sorted correctly.
         """
         if not isinstance(request.data, list):
-            raise ValidationError("The data must be a list.")
+            raise ValidationError({"detail": "The data must be a list."})
 
         # get all item ids to verify, that the user send all ids.
         all_model_ids = set(model.objects.all().values_list("pk", flat=True))
@@ -91,9 +91,11 @@ class TreeSortMixin:
                 node[weight_key] = weight
                 weight += 2
                 if id in ids_found:
-                    raise ValidationError(f"Duplicate id: {id}")
+                    raise ValidationError({"detail": "Duplicate id: {0}", "args": [id]})
                 if id not in all_model_ids:
-                    raise ValidationError(f"Id does not exist: {id}")
+                    raise ValidationError(
+                        {"detail": "Id does not exist: {0}", "args": [id]}
+                    )
                 ids_found.add(id)
 
             # Add children, if exist.
@@ -105,14 +107,17 @@ class TreeSortMixin:
                         child.get("id"), int
                     ):
                         raise ValidationError(
-                            "child must be a dict with an id as integer"
+                            {"detail": "child must be a dict with an id as integer"}
                         )
                     child[parent_id_key] = id
                     nodes_to_check.append(child)
 
         if len(all_model_ids) != len(ids_found):
             raise ValidationError(
-                f"Did not recieved {len(all_model_ids)} ids, got {len(ids_found)}."
+                {
+                    "detail": "Did not recieved {0} ids, got {1}.",
+                    "args": [len(all_model_ids), len(ids_found)],
+                }
             )
 
         # Do the actual update:

tests/integration/motions/test_viewset.py

@@ -927,8 +927,9 @@ class ManageComments(TestCase):
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(
-            response.data["detail"], "A comment section with id 42 does not exist."
+            response.data["detail"], "A comment section with id {0} does not exist."
         )
+        self.assertEqual(response.data["args"][0], "42")
 
     def test_create_comment(self):
         response = self.client.post(
@@ -1309,7 +1310,7 @@ class TestMotionCommentSection(TestCase):
         response = self.client.delete(
             reverse("motioncommentsection-detail", args=[section.pk])
         )
-        self.assertTrue("test_title_SlqfMw(waso0saWMPqcZ" in response.data["detail"])
+        self.assertEqual(response.data["args"][0], '"test_title_SlqfMw(waso0saWMPqcZ"')
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(MotionCommentSection.objects.count(), 1)
 
@@ -1510,12 +1511,8 @@ class CreateMotionChangeRecommendation(TestCase):
             },
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
-        self.assertEqual(
+        self.assertEqual(response.data["args"][0], "3")
-            response.data,
+        self.assertEqual(response.data["args"][1], "6")
-            {
-                "detail": "The recommendation collides with an existing one (line 3 - 6)."
-            },
-        )
 
     def test_no_collission_different_motions(self):
         """
@@ -1635,7 +1632,10 @@ class SetState(TestCase):
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(
             response.data,
-            {"detail": "You can not set the state to %d." % invalid_state_id},
+            {
+                "detail": "You can not set the state to {0}.",
+                "args": [str(invalid_state_id)],
+            },
         )
 
     def test_reset(self):
@@ -1672,7 +1672,10 @@ class SetRecommendation(TestCase):
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertEqual(
             response.data,
-            {"detail": "The recommendation of the motion was set to Acceptance."},
+            {
+                "detail": "The recommendation of the motion was set to {0}.",
+                "args": ["Acceptance"],
+            },
         )
         self.assertEqual(
             Motion.objects.get(pk=self.motion.pk).recommendation.name, "accepted"
@@ -1699,7 +1702,10 @@ class SetRecommendation(TestCase):
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(
             response.data,
-            {"detail": "You can not set the recommendation to %d." % invalid_state_id},
+            {
+                "detail": "You can not set the recommendation to {0}.",
+                "args": [str(invalid_state_id)],
+            },
         )
 
     def test_set_invalid_recommendation(self):
@@ -1712,7 +1718,10 @@ class SetRecommendation(TestCase):
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(
             response.data,
-            {"detail": "You can not set the recommendation to %d." % invalid_state_id},
+            {
+                "detail": "You can not set the recommendation to {0}.",
+                "args": [str(invalid_state_id)],
+            },
         )
 
     def test_set_invalid_recommendation_2(self):
@@ -1727,7 +1736,10 @@ class SetRecommendation(TestCase):
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(
             response.data,
-            {"detail": "You can not set the recommendation to %d." % invalid_state_id},
+            {
+                "detail": "You can not set the recommendation to {0}.",
+                "args": [str(invalid_state_id)],
+            },
         )
 
     def test_reset(self):
@@ -1739,7 +1751,10 @@ class SetRecommendation(TestCase):
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertEqual(
             response.data,
-            {"detail": "The recommendation of the motion was set to None."},
+            {
+                "detail": "The recommendation of the motion was set to {0}.",
+                "args": ["None"],
+            },
         )
         self.assertTrue(Motion.objects.get(pk=self.motion.pk).recommendation is None)
 
@@ -1753,7 +1768,10 @@ class SetRecommendation(TestCase):
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertEqual(
             response.data,
-            {"detail": "The recommendation of the motion was set to Acceptance."},
+            {
+                "detail": "The recommendation of the motion was set to {0}.",
+                "args": ["Acceptance"],
+            },
         )
         self.assertEqual(
             Motion.objects.get(pk=self.motion.pk).recommendation.name, "accepted"
@@ -1839,6 +1857,10 @@ class NumberMotionsInCategories(TestCase):
     """
     Tests numbering motions in categories.
 
+    Default test environment:
+     - *without* blanks
+     - 1 min digit
+
     Testdata. All names (and prefixes) are prefixed with "test_". The
     ordering is ensured with "category_weight".
     Category tree (with motions M and amendments A):
@@ -1926,25 +1948,21 @@ class NumberMotionsInCategories(TestCase):
     def test_numbering(self):
         response = self.client.post(reverse("category-numbering", args=[self.A.pk]))
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        self.assertEqual(Motion.objects.get(pk=self.M1.pk).identifier, "test_A 1")
+        self.assertEqual(Motion.objects.get(pk=self.M1.pk).identifier, "test_A1")
-        self.assertEqual(Motion.objects.get(pk=self.M3.pk).identifier, "test_A 2")
+        self.assertEqual(Motion.objects.get(pk=self.M3.pk).identifier, "test_A2")
-        self.assertEqual(Motion.objects.get(pk=self.M2.pk).identifier, "test_C 3")
+        self.assertEqual(Motion.objects.get(pk=self.M2.pk).identifier, "test_C3")
+        self.assertEqual(Motion.objects.get(pk=self.M2_A1.pk).identifier, "test_C3-2")
         self.assertEqual(
-            Motion.objects.get(pk=self.M2_A1.pk).identifier, "test_C 3 - 2"
+            Motion.objects.get(pk=self.M2_A1_A1.pk).identifier, "test_C3-2-1"
-        )
-        self.assertEqual(
-            Motion.objects.get(pk=self.M2_A1_A1.pk).identifier, "test_C 3 - 2 - 1"
-        )
-        self.assertEqual(
-            Motion.objects.get(pk=self.M2_A2.pk).identifier, "test_C 3 - 1"
         )
+        self.assertEqual(Motion.objects.get(pk=self.M2_A2.pk).identifier, "test_C3-1")
 
-    def test_with_blanks(self):
+    def test_with_blanks_and_leading_zeros(self):
         config["motions_amendments_prefix"] = "-X"
-        config["motions_identifier_with_blank"] = False
+        config["motions_identifier_with_blank"] = True
         config["motions_identifier_min_digits"] = 3
         response = self.client.post(reverse("category-numbering", args=[self.A.pk]))
-        config["motions_identifier_with_blank"] = True
+        config["motions_identifier_with_blank"] = False
         config["motions_identifier_min_digits"] = 1
 
         self.assertEqual(response.status_code, status.HTTP_200_OK)
@@ -1963,16 +1981,17 @@ class NumberMotionsInCategories(TestCase):
         )
 
     def test_existing_identifier_no_category(self):
+        # config["motions_identifier_with_blank"] = True
         conflicting_motion = Motion(
             title="test_title_al2=2k21fjv1lsck3ehlWExg",
             text="test_text_3omvpEhnfg082ejplk1m",
         )
         conflicting_motion.save()
-        conflicting_motion.identifier = "test_C 3 - 2 - 1"
+        conflicting_motion.identifier = "test_C3-2-1"
         conflicting_motion.save()
         response = self.client.post(reverse("category-numbering", args=[self.A.pk]))
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
-        self.assertTrue("test_C 3 - 2 - 1" in response.data["detail"])
+        self.assertEqual("test_C3-2-1", response.data["args"][0])
 
     def test_existing_identifier_with_category(self):
         conflicting_category = Category.objects.create(
@@ -1984,20 +2003,20 @@ class NumberMotionsInCategories(TestCase):
             category=conflicting_category,
         )
         conflicting_motion.save()
-        conflicting_motion.identifier = "test_C 3 - 2 - 1"
+        conflicting_motion.identifier = "test_C3-2-1"
         conflicting_motion.save()
         response = self.client.post(reverse("category-numbering", args=[self.A.pk]))
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
-        self.assertTrue("test_C 3 - 2 - 1" in response.data["detail"])
+        self.assertEqual("test_C3-2-1", response.data["args"][0])
-        self.assertTrue(conflicting_category.name in response.data["detail"])
+        self.assertEqual(conflicting_category.name, response.data["args"][1])
 
     def test_incomplete_amendment_tree(self):
         self.M2_A1.category = None
         self.M2_A1.save()
         response = self.client.post(reverse("category-numbering", args=[self.A.pk]))
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
-        self.assertTrue(self.M2_A1_A1.title in response.data["detail"])
+        self.assertEqual(self.M2_A1_A1.title, response.data["args"][0])
-        self.assertTrue(self.M2_A1.title in response.data["detail"])
+        self.assertEqual(self.M2_A1.title, response.data["args"][1])
 
 
 class TestMotionBlock(TestCase):