Add unique constraint to the exercise translations

This prevents from duplicating translations for exercises. Also, remove
the corresponding health checks since this can't happen anymore.

Author: rolandgeider

wger/exercises/management/commands/exercises-health-check.py

@@ -56,15 +56,6 @@ def add_arguments(self, parser):
             'accessed over the UI)',
         )
 
-        parser.add_argument(
-            '--delete-duplicate-translations',
-            action='store_true',
-            dest='delete_duplicates',
-            default=False,
-            help='Delete duplicate translations (e.g. if an exercise has two French entries, '
-            'the first one will be removed)',
-        )
-
         parser.add_argument(
             '--delete-no-english',
             action='store_true',
@@ -83,64 +74,33 @@ def add_arguments(self, parser):
 
     def handle(self, **options):
         delete_untranslated = options['delete_untranslated'] or options['delete_all']
-        delete_duplicates = options['delete_duplicates'] or options['delete_all']
         delete_no_english = options['delete_no_english'] or options['delete_all']
 
         self.english = Language.objects.get(short_name=ENGLISH_SHORT_NAME)
 
-        for base in Exercise.objects.all():
-            self.handle_untranslated(base, delete_untranslated)
-            self.handle_no_english(base, delete_no_english)
-            self.handle_duplicate_translations(base, delete_duplicates)
+        for exercise in Exercise.objects.all():
+            self.handle_untranslated(exercise, delete_untranslated)
+            self.handle_no_english(exercise, delete_no_english)
 
-    def handle_untranslated(self, base: Exercise, delete: bool):
+    def handle_untranslated(self, exercise: Exercise, delete: bool):
         """
         Delete exercises without translations
         """
-        if not base.pk or base.translations.count():
+        if not exercise.pk or exercise.translations.count():
             return
 
-        self.stdout.write(self.style.WARNING(f'Exercise {base.uuid} has no translations!'))
+        self.stdout.write(self.style.WARNING(f'Exercise {exercise.uuid} has no translations!'))
         if delete:
-            base.delete()
+            exercise.delete()
             self.stdout.write('  -> deleted')
 
-    def handle_no_english(self, base: Exercise, delete: bool):
-        if not base.pk or base.translations.filter(language=self.english).exists():
+    def handle_no_english(self, exercise: Exercise, delete: bool):
+        if not exercise.pk or exercise.translations.filter(language=self.english).exists():
             return
 
-        self.stdout.write(self.style.WARNING(f'Exercise {base.uuid} has no English translation!'))
+        self.stdout.write(
+            self.style.WARNING(f'Exercise {exercise.uuid} has no English translation!')
+        )
         if delete:
-            base.delete()
+            exercise.delete()
             self.stdout.write('  -> deleted')
-
-    def handle_duplicate_translations(self, base: Exercise, delete: bool):
-        if not base.pk:
-            return
-
-        exercise_languages = base.translations.values_list('language', flat=True)
-        duplicates = [
-            Language.objects.get(pk=item)
-            for item, count in collections.Counter(exercise_languages).items()
-            if count > 1
-        ]
-
-        if not duplicates:
-            return
-
-        warning = f'Exercise {base.uuid} has duplicate translations!'
-        self.stdout.write(self.style.WARNING(warning))
-
-        # Output the duplicates
-        for language in duplicates:
-            translations = base.translations.filter(language=language)
-            self.stdout.write(f'language {language.short_name}:')
-            for translation in translations:
-                self.stdout.write(f'  * {translation.name} {translation.uuid}')
-            self.stdout.write('')
-
-            # And delete them
-            if delete:
-                self.stdout.write(f'  Deleting all but first {language.short_name} translation')
-                for translation in translations[1:]:
-                    translation.delete()

wger/exercises/migrations/0033_uniqueness_constraint_translations.py

@@ -0,0 +1,20 @@
+# Generated by Django 5.2.7 on 2025-10-03 19:12
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ('exercises', '0032_rename_exercise'),
+    ]
+
+    operations = [
+        migrations.AddConstraint(
+            model_name='translation',
+            constraint=models.UniqueConstraint(
+                fields=('exercise', 'language'),
+                name='unique_exercise_language_translation',
+                violation_error_message='A translation for this exercise and language already exists.',
+            ),
+        ),
+    ]

wger/exercises/models/translation.py

@@ -105,6 +105,13 @@ class Meta:
             'name',
         ]
         indexes = (GinIndex(fields=['name']),)
+        constraints = [
+            models.UniqueConstraint(
+                fields=['exercise', 'language'],
+                name='unique_exercise_language_translation',
+                violation_error_message='A translation for this exercise and language already exists.',
+            )
+        ]
 
     def get_absolute_url(self):
         """

wger/exercises/tests/test_exercise_translation.py

@@ -30,7 +30,10 @@
     Muscle,
     Translation,
 )
-from wger.utils.constants import CC_BY_SA_4_LICENSE_ID
+from wger.utils.constants import (
+    CC_0_LICENSE_ID,
+    CC_BY_SA_4_LICENSE_ID,
+)
 
 
 class ExerciseRepresentationTestCase(WgerTestCase):
@@ -161,7 +164,7 @@ class ExerciseTranslationCustomApiTestCase(ExerciseCrudApiTestCase):
         'name': 'A new name',
         'description': 'The wild boar is a suid native to much of Eurasia and North Africa',
         'language': 1,
-        'exercise': 2,
+        'exercise': 1,
     }
 
     def get_resource_name(self):
@@ -172,6 +175,7 @@ def test_cant_change_exercise_id(self):
         Test that it is not possible to change the exercise id of an existing
         translation.
         """
+        Translation.objects.filter(exercise_id=2).delete()
         translation = Translation.objects.get(pk=self.pk)
         self.assertEqual(translation.exercise_id, 1)
 
@@ -217,7 +221,7 @@ def test_cant_set_license(self):
         Test that it is not possible to set the license for a newly created
         exercise translation (the license is always set to the default)
         """
-        self.data['license'] = 3
+        self.data['license'] = CC_0_LICENSE_ID
 
         self.authenticate('trainer1')
         response = self.client.post(self.url, data=self.data)
@@ -241,7 +245,7 @@ def test_patch_clean_html(self):
     def test_post_only_one_language_per_base(self):
         """
         Test that it's not possible to add a second translation for the same
-        base in the same language.
+        exercise in the same language.
         """
         self.authenticate('trainer1')
         response = self.client.post(self.url, data=self.data)

wger/exercises/tests/test_management_commands.py

@@ -115,24 +115,3 @@ def test_fix_no_english_translation(self):
         call_command('exercises-health-check', '--delete-no-english', stdout=self.out)
         self.assertIn('-> deleted', self.out.getvalue())
         self.assertRaises(Exercise.DoesNotExist, Exercise.objects.get, pk=1)
-
-    def test_find_duplicate_translations(self):
-        exercise = Translation.objects.get(pk=1)
-        exercise.language_id = 3
-        exercise.save()
-
-        call_command('exercises-health-check', stdout=self.out)
-        self.assertIn(
-            'Exercise acad3949-36fb-4481-9a72-be2ddae2bc05 has duplicate translations!',
-            self.out.getvalue(),
-        )
-        self.assertNotIn('-> deleted', self.out.getvalue())
-
-    def test_fix_duplicate_translations(self):
-        exercise = Translation.objects.get(pk=1)
-        exercise.language_id = 3
-        exercise.save()
-
-        call_command('exercises-health-check', '--delete-duplicate-translations', stdout=self.out)
-        self.assertIn('Deleting all but first fr translation', self.out.getvalue())
-        self.assertRaises(Translation.DoesNotExist, Translation.objects.get, pk=5)