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Diffstat (limited to 'procurement/migrations/0002_add_representative.py')
-rw-r--r-- | procurement/migrations/0002_add_representative.py | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/procurement/migrations/0002_add_representative.py b/procurement/migrations/0002_add_representative.py new file mode 100644 index 0000000..86a2f38 --- /dev/null +++ b/procurement/migrations/0002_add_representative.py @@ -0,0 +1,80 @@ +# Generated by Django 2.1.2 on 2018-10-18 02:18 + +from django.db import migrations, models +import django.db.models.deletion +import warnings + +def copy_reps_forward(apps, editor): + Supplier = apps.get_model("procurement", "Supplier") + Representative = apps.get_model("procurement", "Representative") + suppliers = Supplier.objects.all() + for sup in suppliers: + name = sup.representative_name + email = sup.representative_email + rep = Representative(name=name, email=email, supplier=sup) + rep.save() + +class ReverseMigrationDataLossWarning(UserWarning): + def __init__(self, supplier, kept_rep, lost_reps): + self.supplier = supplier + self.kept_rep = kept_rep + self.lost_reps = lost_reps + + @staticmethod + def format_rep(rep): + return '{} <{}>'.format(rep.name, rep.email) + + def __str__(self): + return "Supplier {} has multiple representatives, only keeping {}. {} will be lost".format(self.supplier.name, self.format_rep(self.kept_rep), [self.format_rep(rep) for rep in self.lost_reps]) + +def copy_reps_rev(apps, editor): + warnings.filterwarnings("always", category=ReverseMigrationDataLossWarning) + Supplier = apps.get_model("procurement", "Supplier") + Representative = apps.get_model("procurement", "Representative") + suppliers = Supplier.objects.all() + for sup in suppliers: + reps = sup.representatives.all() + if reps: + keep = reps[0] + if len(reps) > 1: + lost = reps[1:] + warnings.warn(ReverseMigrationDataLossWarning(sup, keep, lost)) + sup.representative_name = keep.name + sup.representative_email = keep.email + sup.save() + +class Migration(migrations.Migration): + + dependencies = [ + ('procurement', '0001_initial'), + ] + + operations = [ + migrations.CreateModel( + name='Representative', + fields=[ + ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')), + ('created', models.DateTimeField(auto_now_add=True)), + ('updated', models.DateTimeField(auto_now=True)), + ('name', models.CharField(max_length=255)), + ('email', models.CharField(max_length=255)), + ], + options={ + 'abstract': False, + }, + ), + migrations.AddField( + model_name='representative', + name='supplier', + field=models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.CASCADE, related_name='representatives', to='procurement.Supplier'), + ), + migrations.RunPython(copy_reps_forward, copy_reps_rev), + migrations.RemoveField( + model_name='supplier', + name='representative_email', + ), + migrations.RemoveField( + model_name='supplier', + name='representative_name', + ), + ] |