Make recurring_period an Enum, VMProduct a Product, initial wire for

order

uncloud/uncloud_pay/models.py

@@ -1,12 +1,23 @@
 from django.db import models
 from django.contrib.auth import get_user_model
 from django.core.validators import MinValueValidator
+from django.utils.translation import gettext_lazy as _
 
 import uuid
 
 AMOUNT_MAX_DIGITS=10
 AMOUNT_DECIMALS=2
 
+# See https://docs.djangoproject.com/en/dev/ref/models/fields/#field-choices-enum-types
+class RecurringPeriod(models.TextChoices):
+    ONE_TIME   = 'ONCE', _('Onetime')
+    PER_YEAR   = 'YEAR', _('Per Year')
+    PER_MONTH  = 'MONTH', _('Per Month')
+    PER_MINUTE = 'MINUTE', _('Per Minute')
+    PER_DAY    = 'DAY', _('Per Day')
+    PER_HOUR   = 'HOUR', _('Per Hour')
+    PER_SECOND = 'SECOND', _('Per Second')
+
 class Bill(models.Model):
     owner = models.ForeignKey(get_user_model(),
             on_delete=models.CASCADE)
@@ -31,7 +42,7 @@ class Order(models.Model):
                               on_delete=models.CASCADE,
                               editable=False)
 
-    creation_date = models.DateTimeField()
+    creation_date = models.DateTimeField(auto_now_add=True)
     starting_date = models.DateTimeField()
     ending_date = models.DateTimeField(blank=True,
                                        null=True)
@@ -46,19 +57,8 @@ class Order(models.Model):
     one_time_price = models.FloatField(editable=False)
 
     recurring_period = models.CharField(max_length=32,
-                              choices = (
-                                  ('onetime', 'Onetime'),
-                                  ('per_year', 'Per Year'),
-                                  ('per_month', 'Per Month'),
-                                  ('per_week', 'Per Week'),
-                                  ('per_day', 'Per Day'),
-                                  ('per_hour', 'Per Hour'),
-                                  ('per_minute', 'Per Minute'),
-                                  ('per_second', 'Per Second'),
-                              ),
-                              default='onetime'
-
-    )
+                              choices = RecurringPeriod.choices,
+                              default = RecurringPeriod.PER_MONTH)
 
     # def amount(self):
     #     amount = recurring_price
@@ -133,7 +133,12 @@ class Product(models.Model):
 
     order = models.ForeignKey(Order,
                               on_delete=models.CASCADE,
-                              editable=False)
+                              editable=False,
+                              null=True)
+
+    @property
+    def recurring_price(self, recurring_period=RecurringPeriod.PER_MONTH):
+        pass # To be implemented in child.
 
     class Meta:
         abstract = True