Split migrations

- move create publication to core
- use ivm entries for the nutrition publications

wger/core/migrations/0018_create_publication_add_ivm_extension.py

@@ -0,0 +1,48 @@
+# Generated by Django 4.2.13 on 2024-09-19 13:43
+
+from django.db import migrations
+
+from wger.utils.db import postgres_only
+
+
+@postgres_only
+def add_publication(apps, schema_editor):
+    # Note that "FOR ALL TABLES" applies for all tables created in the future as well
+    schema_editor.execute(
+        """
+        DO $$
+        BEGIN
+            IF NOT EXISTS (
+                SELECT 1 FROM pg_publication WHERE pubname = 'powersync'
+            ) THEN
+                CREATE PUBLICATION powersync FOR ALL TABLES;
+            END IF;
+        END $$;
+        """
+    )
+
+
+@postgres_only
+def remove_publication(apps, schema_editor):
+    schema_editor.execute('DROP PUBLICATION IF EXISTS powersync;')
+
+
+@postgres_only
+def add_ivm_extension(apps, schema_editor):
+    schema_editor.execute('CREATE EXTENSION IF NOT EXISTS pg_ivm;')
+
+
+@postgres_only
+def remove_ivm_extension(apps, schema_editor):
+    schema_editor.execute('DROP EXTENSION IF EXISTS pg_ivm;')
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ('core', '0017_language_full_name_en'),
+    ]
+
+    operations = [
+        migrations.RunPython(add_publication, reverse_code=remove_publication),
+        migrations.RunPython(add_ivm_extension, reverse_code=remove_ivm_extension),
+    ]

wger/nutrition/migrations/0025_create_ivm_entries.py

@@ -0,0 +1,69 @@
+from django.db import migrations
+
+from wger.utils.db import postgres_only
+
+
+@postgres_only
+def add_ivm_views(apps, schema_editor):
+    """
+    Note: the select statements are written a bit weirdly because of this issue
+    https://github.com/sraoss/pg_ivm/issues/85
+
+    When this is resolved, we can remove the subqueries and write e.g.
+
+    SELECT m.*, p.user_id
+    FROM nutrition_meal AS m
+    JOIN nutrition_nutritionplan AS p ON m.plan_id = p.id;
+    """
+
+    schema_editor.execute(
+        """
+        SELECT create_immv(
+            'ivm_nutrition_meal',
+            'SELECT m.*, p.user_id
+                FROM (SELECT * FROM nutrition_meal) AS m
+                JOIN (SELECT id, user_id FROM nutrition_nutritionplan) AS p ON m.plan_id = p.id;'
+            );
+        """
+    )
+
+    schema_editor.execute(
+        """
+        SELECT create_immv(
+            'ivm_nutrition_mealitem',
+            'SELECT mi.*, p.user_id
+                FROM (SELECT * FROM nutrition_mealitem) AS mi
+                JOIN (SELECT id, plan_id FROM nutrition_meal) AS m ON mi.meal_id = m.id
+                JOIN (SELECT id, user_id FROM nutrition_nutritionplan) AS p ON m.plan_id = p.id;'
+            );
+        """
+    )
+
+    schema_editor.execute(
+        """
+        SELECT create_immv(
+            'ivm_nutrition_logitem',
+            'SELECT li.*, p.user_id
+                FROM (SELECT * FROM nutrition_logitem) AS li
+                JOIN (SELECT id, user_id FROM nutrition_nutritionplan) AS p ON li.plan_id = p.id;'
+            );
+        """
+    )
+
+
+@postgres_only
+def remove_ivm_views(apps, schema_editor):
+    schema_editor.execute('DROP TABLE IF EXISTS ivm_nutrition_mealitem;')
+    schema_editor.execute('DROP TABLE IF EXISTS ivm_nutrition_meal;')
+    schema_editor.execute('DROP TABLE IF EXISTS ivm_nutrition_logitem;')
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ('nutrition', '0024_remove_ingredient_status'),
+        ('core', '0018_create_publication_add_ivm_extension'),
+    ]
+
+    operations = [
+        migrations.RunPython(add_ivm_views, reverse_code=remove_ivm_views),
+    ]

wger/utils/db.py

@@ -12,9 +12,25 @@
 #
 # You should have received a copy of the GNU Affero General Public License
 
+# Standard Library
+from functools import wraps
+
 # Django
 from django.conf import settings
 
 
 def is_postgres_db():
     return 'postgres' in settings.DATABASES['default']['ENGINE']
+
+
+def postgres_only(func):
+    """Decorator that runs the decorated function only if the database is PostgreSQL."""
+
+    @wraps(func)
+    def wrapper(*args, **kwargs):
+        if is_postgres_db():
+            return func(*args, **kwargs)
+        else:
+            return
+
+    return wrapper