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# 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',
),
]
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