Agrego migración de borrado de periodicities duplicadas

series_tiempo_ar_api/apps/management/migrations/delete_duplicated_metadata.py

@@ -0,0 +1,33 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.6 on 2019-02-08 18:09
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+from series_tiempo_ar_api.apps.management import meta_keys
+
+
+def delete_all_but_last_periodicity(apps, schema_editor):
+    Metadata = apps.get_model('django_datajsonar', 'Metadata')
+    db_alias = schema_editor.connection.alias
+
+    found_distributions = set()
+    periodicites= Metadata.objects.using(db_alias).filter(key=meta_keys.PERIODICITY).order_by('-id')
+
+    for metadata in periodicites:
+        distribution = metadata.object_id
+        if distribution in found_distributions:
+            metadata.delete()
+
+        found_distributions.add(distribution)
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('management', '0006_auto_20190208_1509'),
+    ]
+
+    operations = [
+        migrations.RunPython(delete_all_but_last_periodicity)
+    ]