WIP revamped bill logic

This commit is contained in:
fnux 2020-02-29 09:08:30 +01:00
parent af1265003e
commit e319d1d151
7 changed files with 152 additions and 69 deletions

View file

@ -1,7 +1,10 @@
from functools import reduce
from datetime import datetime
from rest_framework import mixins
from rest_framework.viewsets import GenericViewSet
from .models import Bill, Payment, PaymentMethod
from django.db.models import Q
from .models import Bill, Payment, PaymentMethod, Order
from django.utils import timezone
def sum_amounts(entries):
return reduce(lambda acc, entry: acc + entry.amount, entries, 0)
@ -20,6 +23,52 @@ def get_payment_method_for(user):
return None
def beginning_of_month(date):
return datetime(year=date.year, date=now.month, day=0)
def generate_bills_for(year, month, user, allowed_delay):
# /!\ We exclusively work on the specified year and month.
# Default values for next bill (if any). Only saved at the end of
# this method, if relevant.
tz = timezone.get_current_timezone()
next_bill = Bill(owner=user,
starting_date=datetime(year=year, month=month, day=1, tzinfo=tz),
ending_date=datetime(year=year, month=month, day=28, tzinfo=tz),
creation_date=timezone.now(),
due_date=timezone.now() + allowed_delay)
# Select all orders active on the request period.
orders = Order.objects.filter(
Q(ending_date__gt=next_bill.starting_date) | Q(ending_date__isnull=True),
owner=user)
# Check if there is already a bill covering the order and period pair:
# * Get latest bill by ending_date: previous_bill.ending_date
# * If previous_bill.ending_date is before next_bill.ending_date, a new
# bill has to be generated.
unpaid_orders = []
for order in orders:
try:
previous_bill = order.bill.latest('-ending_date')
except ObjectDoesNotExist:
previous_bill = None
if previous_bill == None or previous_bill.ending_date < next_bill.ending_date:
unpaid_orders.append(order)
# Commit next_bill if it there are 'unpaid' orders.
if len(unpaid_orders) > 0:
next_bill.save()
# It is not possible to register many-to-many relationship before
# the two end-objects are saved in database.
for order in unpaid_orders:
order.bill.add(next_bill)
return next_bill
# Return None if no bill was created.
class ProductViewSet(mixins.CreateModelMixin,
mixins.RetrieveModelMixin,

View file

@ -1,67 +1,38 @@
import logging
from django.core.management.base import BaseCommand
from uncloud_auth.models import User
from uncloud_pay.models import Order, Bill
from django.core.exceptions import ObjectDoesNotExist
from datetime import timedelta
from datetime import timedelta, date
from django.utils import timezone
from uncloud_pay.helpers import generate_bills_for
BILL_PAYMENT_DELAY=timedelta(days=10)
logger = logging.getLogger(__name__)
class Command(BaseCommand):
help = 'Generate bills and charge customers if necessary.'
def add_arguments(self, parser):
pass
# TODO: use logger.*
def handle(self, *args, **options):
# Iterate over all 'active' users.
# TODO: filter out inactive users.
users = User.objects.all()
print("Processing {} users.".format(users.count()))
for user in users:
# Fetch all the orders of a customer.
orders = Order.objects.filter(owner=user)
# Default values for next bill (if any). Only saved at the end of
# this method, if relevant.
next_bill = Bill(owner=user,
starting_date=timezone.now(), # Will be set to oldest unpaid order (means unpaid starting date).
ending_date=timezone.now(), # Bill covers everything until today.
due_date=timezone.now() + BILL_PAYMENT_DELAY)
unpaid_orders = [] # Store orders in need of a payment.
for order in orders:
# Only bill if there is an 'unpaid period' on an active order.
# XXX: Assume everything before latest bill is paid. => might be dangerous.
try:
previous_bill = order.bill.latest('ending_date')
except ObjectDoesNotExist:
previous_bill = None
is_unpaid_period = True
if order.ending_date and previous_bill != None:
is_unpaid_period = previous_bill.ending_date < order.ending_date
if is_unpaid_period:
# Update bill starting date to match period.
if previous_bill == None:
next_bill.starting_date = order.starting_date
elif previous_bill.ending_date < next_bill.starting_date:
next_bill.starting_date = previous_bill.ending_date
# Add order to bill
unpaid_orders.append(order)
# Save next_bill if it contains any unpaid product.
if len(unpaid_orders) > 0:
next_bill.save()
# It is not possible to register many-to-many relationship before
# the two end-objects are saved in database.
for order in unpaid_orders:
order.bill.add(next_bill)
print("Created bill {} for user {}".format(next_bill.uuid, user.username))
now = timezone.now()
generate_bills_for(
year=now.year,
month=now.month,
user=user,
allowed_delay=BILL_PAYMENT_DELAY)
# We're done for this round :-)
print("=> Done.")

View file

@ -2,6 +2,7 @@ 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 _
from django.utils import timezone
import uuid
@ -31,16 +32,49 @@ class Bill(models.Model):
valid = models.BooleanField(default=True)
@property
def amount(self):
orders = Order.objects.filter(bill=self)
amount = 0
for order in orders:
amount += order.recurring_price
return amount
def entries(self):
# TODO: return list of Bill entries, extract from linked order
# for each related order
# for each product
# build BillEntry
return []
@property
def total(self):
#return helpers.sum_amounts(self.entries)
pass
class BillEntry():
start_date = timezone.now()
end_date = timezone.now()
recurring_period = RecurringPeriod.PER_MONTH
recurring_price = 0
amount = 0
description = ""
# /!\ BIG FAT WARNING /!\ #
#
# Order are assumed IMMUTABLE and used as SOURCE OF TRUST for generating
# bills. Do **NOT** mutate then!
#
# Why? We need to store the state somewhere since product are mutable (e.g.
# adding RAM to VM, changing price of 1GB of RAM, ...). An alternative could
# have been to only store the state in bills but would have been more
# confusing: the order is a 'contract' with the customer, were both parts
# agree on deal => That's what we want to keep archived.
#
# SOON:
#
# We'll need to add some kind of OrderEntry table (each order might have
# multiple entries) storing: recurring_price, recurring_period, setup_fee, description
#
# FOR NOW:
#
# We dynamically get pricing from linked product, as they are not updated in
# this stage of development.
#
# /!\ BIG FAT WARNING /!\ #
class Order(models.Model):
uuid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
owner = models.ForeignKey(get_user_model(),
@ -56,22 +90,11 @@ class Order(models.Model):
editable=False,
blank=True)
recurring_price = models.DecimalField(
max_digits=AMOUNT_MAX_DIGITS,
decimal_places=AMOUNT_DECIMALS,
validators=[MinValueValidator(0)],
editable=False)
one_time_price = models.DecimalField(
max_digits=AMOUNT_MAX_DIGITS,
decimal_places=AMOUNT_DECIMALS,
validators=[MinValueValidator(0)],
editable=False)
recurring_period = models.CharField(max_length=32,
choices = RecurringPeriod.choices,
default = RecurringPeriod.PER_MONTH)
# def amount(self):
# amount = recurring_price
# if recurring and first_month:
@ -133,9 +156,6 @@ class Payment(models.Model):
default='unknown')
timestamp = models.DateTimeField(editable=False, auto_now_add=True)
class Product(models.Model):
uuid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
owner = models.ForeignKey(get_user_model(),

View file

@ -0,0 +1,18 @@
# Generated by Django 3.0.3 on 2020-02-28 14:16
from django.db import migrations, models
class Migration(migrations.Migration):
dependencies = [
('uncloud_vm', '0008_vmproduct_name'),
]
operations = [
migrations.AlterField(
model_name='vmproduct',
name='name',
field=models.CharField(max_length=32),
),
]

View file

@ -0,0 +1,18 @@
# Generated by Django 3.0.3 on 2020-02-28 14:16
from django.db import migrations, models
class Migration(migrations.Migration):
dependencies = [
('ungleich_service', '0001_initial'),
]
operations = [
migrations.AddField(
model_name='matrixserviceproduct',
name='domain',
field=models.CharField(default='domain.tld', max_length=255),
),
]

View file

@ -1,6 +1,7 @@
from rest_framework import serializers
from .models import MatrixServiceProduct
from uncloud_vm.serializers import VMProductSerializer
from uncloud_vm.models import VMProduct
class MatrixServiceProductSerializer(serializers.ModelSerializer):
vm = VMProductSerializer()
@ -9,3 +10,9 @@ class MatrixServiceProductSerializer(serializers.ModelSerializer):
model = MatrixServiceProduct
fields = ['uuid', 'order', 'owner', 'status', 'vm', 'domain']
read_only_fields = ['uuid', 'order', 'owner', 'status']
def create(self, validated_data):
# Create VM
vm_data = validated_data.pop('vm')
vm = VMProduct.objects.create(**vm_data)
return MatrixServiceProduct.create(vm=vm, **validated_data)

View file

@ -13,5 +13,5 @@ class MatrixServiceProductViewSet(ProductViewSet):
return MatrixServiceProduct.objects.filter(owner=self.request.user)
def create(self, request):
# TODO
pass
# TODO: create order, register service
return Response('{"HIT!"}')