Added: Add server-side playlist validation to rules files

backend/experiment/forms.py

@@ -170,6 +170,30 @@ def __init__(self, *args, **kwargs):
             required=False
         )
 
+    def clean_playlists(self):
+
+        # Check if there is a rules id selected and key exists
+        if 'rules' not in self.cleaned_data:
+            return
+
+        # Validat the rules' playlist
+        rule_id = self.cleaned_data['rules']
+        cl = EXPERIMENT_RULES[rule_id]
+        rules = cl()
+
+        playlists = self.cleaned_data['playlists']
+        playlist_errors = []
+
+        # Validate playlists
+        for playlist in playlists:
+            errors = rules.validate_playlist(playlist)
+
+            for error in errors:
+                playlist_errors.append(f"Playlist [{playlist.name}]: {error}")
+
+        if playlist_errors:
+            self.add_error('playlists', playlist_errors)
+
     class Meta:
         model = Experiment
         fields = ['name', 'slug', 'active', 'rules',

backend/experiment/rules/base.py

@@ -5,6 +5,8 @@
 from django.conf import settings
 
 from experiment.actions import Final, Form, Trial
+from experiment.models import Experiment
+from section.models import Playlist
 from experiment.questions.demographics import DEMOGRAPHICS
 from experiment.questions.goldsmiths import MSI_OTHER
 from experiment.questions.utils import question_by_key, unanswered_questions
@@ -156,3 +158,17 @@ def social_media_info(self, experiment, score):
             'url': experiment.url or current_url,
             'hashtags': [experiment.hashtag or experiment.slug, "amsterdammusiclab", "citizenscience"]
         }
+
+    def validate_playlist(self, playlist: Playlist):
+        errors = []
+        # Common validations across experiments
+        if not playlist:
+            errors.append('The experiment must have a playlist.')
+            return errors
+
+        sections = playlist.section_set.all()
+
+        if not sections:
+            errors.append('The experiment must have at least one section.')
+
+        return errors

backend/experiment/rules/congosamediff.py

@@ -1,7 +1,6 @@
 
 import random
 import re
-import math
 import string
 from django.utils.translation import gettext_lazy as _
 from experiment.actions.utils import final_action_with_optional_button
@@ -30,7 +29,9 @@ def first_round(self, experiment: Experiment):
         """
 
         # Do a validity check on the experiment
-        self.validate(experiment)
+        errors = self.validate_playlist(experiment.playlists.first())
+        if errors:
+            raise ValueError('The experiment playlist is not valid: \n- ' + '\n- '.join(errors))
 
         # 1. Playlist
         playlist = Playlist(experiment.playlists.all())
@@ -241,12 +242,14 @@ def get_total_trials_count(self, session: Session):
         total_trials_count = practice_trials_count + total_unique_exp_trials_count + 1
         return total_trials_count
 
-    def validate(self, experiment: Experiment):
+    def validate_playlist(self, playlist: PlaylistModel):
 
         errors = []
 
+        super().validate_playlist(playlist)  # Call the base class validate_playlist to perform common checks
+
         # All sections need to have a group value
-        sections = experiment.playlists.first().section_set.all()
+        sections = playlist.section_set.all()
         for section in sections:
             file_name = section.song.name if section.song else 'No name'
             # every section.group should consist of a number
@@ -265,7 +268,7 @@ def validate(self, experiment: Experiment):
         if not sections.exclude(tag__contains='practice').exists():
             errors.append('At least one section should not have the tag "practice"')
 
-        # Every non-practice group should have the same number of variants 
+        # Every non-practice group should have the same number of variants
         # that should be labeled with a single uppercase letter
         groups = sections.values('group').distinct()
         variants = sections.exclude(tag__contains='practice').values('tag')
@@ -283,8 +286,7 @@ def validate(self, experiment: Experiment):
                 total_variants_stringified = ', '.join(unique_variants)
                 errors.append(f'Group {group["group"]} should have the same number of variants as the total amount of variants ({variants_count}; {total_variants_stringified}) but has {group_variants.count()} ({group_variants_stringified})')
 
-        if errors:
-            raise ValueError('The experiment playlist is not valid: \n- ' + '\n- '.join(errors))
+        return errors
 
     def get_participant_group_variant(self, participant_id: int, group_number: int, groups_amount: int, variants_amount: int) -> str:
 

backend/experiment/rules/tests/test_base.py

@@ -1,6 +1,7 @@
 from django.test import TestCase
 from django.conf import settings
 from experiment.models import Experiment
+from section.models import Playlist
 from ..base import Base
 
 
@@ -27,3 +28,13 @@ def test_social_media_info(self):
         # Check for double slashes
         self.assertNotIn(social_media_info['url'], '//')
         self.assertEqual(social_media_info['hashtags'], ['music-lab', 'amsterdammusiclab', 'citizenscience'])
+
+    def test_validate_playlist(self):
+        base = Base()
+        playlist = None
+        errors = base.validate_playlist(playlist)
+        self.assertEqual(errors, ['The experiment must have a playlist.'])
+
+        playlist = Playlist()
+        errors = base.validate_playlist(playlist)
+        self.assertEqual(errors, ['The experiment must have at least one section.'])

backend/experiment/urls.py

@@ -1,12 +1,13 @@
 from django.urls import path
 from django.views.generic.base import TemplateView
-from .views import get_experiment, get_experiment_collection, post_feedback, default_questions, render_markdown
+from .views import get_experiment, get_experiment_collection, post_feedback, default_questions, render_markdown, validate_experiment_playlist
 
 app_name = 'experiment'
 
 urlpatterns = [
     # Experiment
     path('render_markdown/', render_markdown, name='render_markdown'),
+    path('validate_playlist/<str:rules_id>', validate_experiment_playlist, name='validate_experiment_playlist'),
     path('<slug:slug>/', get_experiment, name='experiment'),
     path('<slug:slug>/feedback/', post_feedback, name='feedback'),
     path('collection/<slug:slug>/', get_experiment_collection,

backend/experiment/views.py

@@ -7,6 +7,7 @@
 from django_markup.markup import formatter
 
 from .models import Experiment, ExperimentCollection, ExperimentCollectionGroup, Feedback
+from section.models import Playlist
 from experiment.serializers import serialize_actions, serialize_experiment_collection, serialize_experiment_collection_group
 from experiment.rules import EXPERIMENT_RULES
 from experiment.actions.utils import COLLECTION_KEY
@@ -132,3 +133,48 @@ def render_markdown(request):
         return JsonResponse({'html': formatter(markdown, filter_name='markdown')})
 
     return JsonResponse({'html': ''})
+
+
+def validate_experiment_playlist(
+        request: HttpRequest,
+        rules_id: str
+        ) -> JsonResponse:
+    """
+    Validate the playlist of an experiment based on the used rules
+    """
+
+    if request.method != 'POST':
+        return JsonResponse({'status': 'error', 'message': 'Only POST requests are allowed'})
+
+    if not request.body:
+        return JsonResponse({'status': 'error', 'message': 'No body found in request'})
+
+    if request.content_type != 'application/json':
+        return JsonResponse({'status': 'error', 'message': 'Only application/json content type is allowed'})
+
+    json_body = json.loads(request.body)
+    playlist_ids = json_body.get('playlists', [])
+    playlists = Playlist.objects.filter(id__in=playlist_ids)
+
+    if not playlists:
+        return JsonResponse({'status': 'error', 'message': 'The experiment must have a playlist.'})
+
+    rules = EXPERIMENT_RULES[rules_id]()
+
+    if not rules.validate_playlist:
+        return JsonResponse({'status': 'warn', 'message': 'This rulesset does not have a playlist validation.'})
+
+    playlist_errors = []
+
+    for playlist in playlists:
+        errors = rules.validate_playlist(playlist)
+        if errors:
+            playlist_errors.append({
+                'playlist': playlist.name,
+                'errors': errors
+                })
+
+    if playlist_errors:
+        return JsonResponse({'status': 'error', 'message': 'There are errors in the playlist.', 'errors': playlist_errors})
+
+    return JsonResponse({'status': 'ok', 'message': 'The playlist is valid.'})