Allow to select billing period when registering VM

uncloud/uncloud_pay/models.py

@@ -299,5 +299,9 @@ class Product(models.Model):
     def setup_fee(self):
         return 0
 
+    @property
+    def recurring_period(self):
+        return self.order.recurring_period
+
     class Meta:
         abstract = True

uncloud/uncloud_vm/models.py

@@ -47,9 +47,11 @@ class VMProduct(Product):
     ram_in_gb = models.FloatField()
 
     def recurring_price(self, recurring_period=RecurringPeriod.PER_MONTH):
+        # TODO: move magic numbers in variables
         if recurring_period == RecurringPeriod.PER_MONTH:
-            # TODO: move magic numbers in variables
             return self.cores * 3 + self.ram_in_gb * 2
+        elif recurring_period == RecurringPeriod.PER_HOUR:
+            return self.cores * 4.0/(30 * 24) + self.ram_in_gb * 3.0/(30* 24)
         else:
             raise Exception('Invalid recurring period for VM Product pricing.')
 

uncloud/uncloud_vm/serializers.py

@@ -2,6 +2,7 @@ from django.contrib.auth import get_user_model
 
 from rest_framework import serializers
 from .models import VMHost, VMProduct, VMSnapshotProduct
+from uncloud_pay.models import RecurringPeriod
 
 class VMHostSerializer(serializers.HyperlinkedModelSerializer):
     class Meta:
@@ -10,10 +11,19 @@ class VMHostSerializer(serializers.HyperlinkedModelSerializer):
 
 
 class VMProductSerializer(serializers.HyperlinkedModelSerializer):
+    # TODO: move this to VMProduct.
+    allowed_recurring_periods=list(filter(
+        lambda pair: pair[0] in [RecurringPeriod.PER_MONTH, RecurringPeriod.PER_HOUR],
+        RecurringPeriod.choices))
+
+    # Custom field used at creation (= ordering) only.
+    recurring_period = serializers.ChoiceField(
+            choices=allowed_recurring_periods)
+
     class Meta:
         model = VMProduct
         fields = ['uuid', 'order', 'owner', 'status', 'name', \
-                'cores', 'ram_in_gb']
+                'cores', 'ram_in_gb', 'recurring_period']
         read_only_fields = ['uuid', 'order', 'owner', 'status']
 
 class VMSnapshotProductSerializer(serializers.ModelSerializer):

uncloud/uncloud_vm/views.py

@@ -32,19 +32,23 @@ class VMProductViewSet(ProductViewSet):
     # if something goes wrong.
     @transaction.atomic
     def create(self, request):
+        # Extract serializer data.
+        serializer = VMProductSerializer(data=request.data, context={'request': request})
+        serializer.is_valid(raise_exception=True)
+        order_recurring_period = serializer.validated_data.pop("recurring_period")
+
         # Create base order.
         order = Order.objects.create(
-                recurring_period=RecurringPeriod.PER_MONTH,
+                recurring_period=order_recurring_period,
                 owner=request.user
                 )
         order.save()
 
         # Create VM.
-        serializer = VMProductSerializer(data=request.data, context={'request': request})
-        serializer.is_valid(raise_exception=True)
         vm = serializer.save(owner=request.user, order=order)
 
         # Add Product record to order (VM is mutable, allows to keep history in order).
+        # XXX: Move this to some kind of on_create hook in parent Product class?
         order.add_record(vm.setup_fee,
                 vm.recurring_price(order.recurring_period), vm.description)