django-orchestra/orchestra/contrib/services/handlers.py

641 lines
28 KiB
Python

import calendar
import datetime
import decimal
import math
from functools import cmp_to_key
from dateutil import relativedelta
from django.contrib.contenttypes.models import ContentType
from django.core.exceptions import ValidationError
from django.utils import timezone, translation
from django.utils.translation import ugettext, ugettext_lazy as _
from orchestra import plugins
from orchestra.utils.humanize import text2int
from orchestra.utils.python import AttrDict, format_exception
from . import settings, helpers
class ServiceHandler(plugins.Plugin, metaclass=plugins.PluginMount):
"""
Separates all the logic of billing handling from the model allowing to better
customize its behaviout
Relax and enjoy the journey.
"""
_PLAN = 'plan'
_COMPENSATION = 'compensation'
_PREPAY = 'prepay'
model = None
def __init__(self, service):
self.service = service
def __getattr__(self, attr):
return getattr(self.service, attr)
@classmethod
def get_choices(cls):
choices = super(ServiceHandler, cls).get_choices()
return [('', _("Default"))] + choices
def validate_content_type(self, service):
pass
def validate_expression(self, service, method):
try:
obj = service.content_type.model_class().objects.all()[0]
except IndexError:
return
try:
bool(getattr(self, method)(obj))
except Exception as exc:
raise ValidationError(format_exception(exc))
def validate_match(self, service):
if not service.match:
service.match = 'True'
self.validate_expression(service, 'matches')
def validate_metric(self, service):
self.validate_expression(service, 'get_metric')
def validate_order_description(self, service):
self.validate_expression(service, 'get_order_description')
def get_content_type(self):
if not self.model:
return self.content_type
app_label, model = self.model.split('.')
return ContentType.objects.get_by_natural_key(app_label, model.lower())
def get_expression_context(self, instance):
return {
'instance': instance,
'obj': instance,
'ugettext': ugettext,
'handler': self,
'service': self.service,
instance._meta.model_name: instance,
'math': math,
'logsteps': lambda n, size=1: \
round(n/(decimal.Decimal(size*10**int(math.log10(max(n, 1))))))*size*10**int(math.log10(max(n, 1))),
'log10': math.log10,
'Decimal': decimal.Decimal,
}
def matches(self, instance):
if not self.match:
# Blank expressions always evaluate True
return True
safe_locals = self.get_expression_context(instance)
return eval(self.match, safe_locals)
def get_ignore_delta(self):
if self.ignore_period == self.NEVER:
return None
value, unit = self.ignore_period.split('_')
value = text2int(value)
if unit.lower().startswith('day'):
return datetime.timedelta(days=value)
if unit.lower().startswith('month'):
return datetime.timedelta(months=value)
else:
raise ValueError("Unknown unit %s" % unit)
def get_order_ignore(self, order):
""" service trial delta """
ignore_delta = self.get_ignore_delta()
if ignore_delta and (order.cancelled_on-ignore_delta).date() <= order.registered_on:
return True
return order.ignore
def get_ignore(self, instance):
if self.ignore_superusers:
account = getattr(instance, 'account', instance)
if account.type in settings.SERVICES_IGNORE_ACCOUNT_TYPE:
return True
if 'superuser' in settings.SERVICES_IGNORE_ACCOUNT_TYPE and account.is_superuser:
return True
return False
def get_metric(self, instance):
if self.metric:
safe_locals = self.get_expression_context(instance)
try:
return eval(self.metric, safe_locals)
except Exception as exc:
raise type(exc)("%s on '%s'" %(exc, self.service))
def get_order_description(self, instance):
safe_locals = self.get_expression_context(instance)
account = getattr(instance, 'account', instance)
with translation.override(account.language):
if not self.order_description:
return '%s: %s' % (ugettext(self.description), instance)
return eval(self.order_description, safe_locals)
def get_billing_point(self, order, bp=None, **options):
cachable = bool(self.billing_point == self.FIXED_DATE and not options.get('fixed_point'))
if not cachable or bp is None:
bp = options.get('billing_point') or timezone.now().date()
if not options.get('fixed_point'):
msg = ("Support for '%s' period and '%s' point is not implemented"
% (self.get_billing_period_display(), self.get_billing_point_display()))
if self.billing_period == self.MONTHLY:
date = bp
if self.payment_style == self.PREPAY:
date += relativedelta.relativedelta(months=1)
else:
date = timezone.now().date()
if self.billing_point == self.ON_REGISTER:
day = order.registered_on.day
elif self.billing_point == self.FIXED_DATE:
day = 1
else:
raise NotImplementedError(msg)
bp = datetime.date(year=date.year, month=date.month, day=day)
elif self.billing_period == self.ANUAL:
if self.billing_point == self.ON_REGISTER:
month = order.registered_on.month
day = order.registered_on.day
elif self.billing_point == self.FIXED_DATE:
month = settings.SERVICES_SERVICE_ANUAL_BILLING_MONTH
day = 1
else:
raise NotImplementedError(msg)
year = bp.year
if self.payment_style == self.POSTPAY:
year = bp.year - relativedelta.relativedelta(years=1)
if bp.month >= month:
year = bp.year + 1
bp = datetime.date(year=year, month=month, day=day)
elif self.billing_period == self.NEVER:
bp = order.registered_on
else:
raise NotImplementedError(msg)
if self.on_cancel != self.NOTHING and order.cancelled_on and order.cancelled_on < bp:
bp = order.cancelled_on
return bp
# def aligned(self, date):
# if self.granularity == self.DAILY:
# return date
# elif self.granularity == self.MONTHLY:
# return datetime.date(year=date.year, month=date.month, day=1)
# elif self.granularity == self.ANUAL:
# return datetime.date(year=date.year, month=1, day=1)
# raise NotImplementedError
def get_price_size(self, ini, end):
rdelta = relativedelta.relativedelta(end, ini)
anual_prepay_of_monthly_pricing = bool(
self.billing_period == self.ANUAL and
self.payment_style == self.PREPAY and
self.get_pricing_period() == self.MONTHLY)
if self.billing_period == self.MONTHLY or anual_prepay_of_monthly_pricing:
size = rdelta.years * 12
size += rdelta.months
days = calendar.monthrange(end.year, end.month)[1]
size += decimal.Decimal(str(rdelta.days))/days
elif self.billing_period == self.ANUAL:
size = rdelta.years
size += decimal.Decimal(str(rdelta.months))/12
days = 366 if calendar.isleap(end.year) else 365
size += decimal.Decimal(str(rdelta.days))/days
elif self.billing_period == self.NEVER:
size = 1
else:
raise NotImplementedError
size = round(size, 2)
return decimal.Decimal(str(size))
def get_pricing_slots(self, ini, end):
day = 1
month = settings.SERVICES_SERVICE_ANUAL_BILLING_MONTH
if self.billing_point == self.ON_REGISTER:
day = ini.day
month = ini.month
period = self.get_pricing_period()
rdelta = self.get_pricing_rdelta()
if period == self.MONTHLY:
ini = datetime.date(year=ini.year, month=ini.month, day=day)
elif period == self.ANUAL:
ini = datetime.date(year=ini.year, month=month, day=day)
elif period == self.NEVER:
yield ini, end
raise StopIteration
else:
raise NotImplementedError
while True:
next = ini + rdelta
yield ini, next
if next >= end:
break
ini = next
def get_pricing_rdelta(self):
period = self.get_pricing_period()
if period == self.MONTHLY:
return relativedelta.relativedelta(months=1)
elif period == self.ANUAL:
return relativedelta.relativedelta(years=1)
elif period == self.NEVER:
return None
def generate_discount(self, line, dtype, price):
line.discounts.append(AttrDict(**{
'type': dtype,
'total': price,
}))
def generate_line(self, order, price, *dates, metric=1, discounts=None, computed=False):
"""
discounts: extra discounts to apply
computed: price = price*size already performed
"""
if len(dates) == 2:
ini, end = dates
elif len(dates) == 1:
ini, end = dates[0], dates[0]
else:
raise AttributeError("WTF is '%s'?" % dates)
discounts = discounts or ()
size = self.get_price_size(ini, end)
if not computed:
price = price * size
subtotal = self.nominal_price * size * metric
line = AttrDict(**{
'order': order,
'subtotal': subtotal,
'ini': ini,
'end': end,
'size': size,
'metric': metric,
'discounts': [],
})
if subtotal > price:
plan_discount = price-subtotal
self.generate_discount(line, self._PLAN, plan_discount)
subtotal += plan_discount
for dtype, dprice in discounts:
subtotal += dprice
# Prevent compensations/prepays to refund money
if dtype in (self._COMPENSATION, self._PREPAY) and subtotal < 0:
dprice -= subtotal
if dprice:
self.generate_discount(line, dtype, dprice)
return line
def assign_compensations(self, givers, receivers, **options):
compensations = []
for order in givers:
if order.billed_until and order.cancelled_on and order.cancelled_on < order.billed_until:
interval = helpers.Interval(order.cancelled_on, order.billed_until, order)
compensations.append(interval)
for order in receivers:
if not order.billed_until or order.billed_until < order.new_billed_until:
# receiver
ini = order.billed_until or order.registered_on
end = order.cancelled_on or datetime.date.max
interval = helpers.Interval(ini, end)
compensations, used_compensations = helpers.compensate(interval, compensations)
order._compensations = used_compensations
for comp in used_compensations:
comp.order.new_billed_until = min(comp.order.billed_until, comp.ini,
getattr(comp.order, 'new_billed_until', datetime.date.max))
if options.get('commit', True):
for order in givers:
if hasattr(order, 'new_billed_until'):
order.billed_until = order.new_billed_until
order.save(update_fields=['billed_until'])
def apply_compensations(self, order, only_beyond=False):
dsize = 0
ini = order.billed_until or order.registered_on
end = order.new_billed_until
beyond = end
cend = None
for comp in getattr(order, '_compensations', []):
intersect = comp.intersect(helpers.Interval(ini=ini, end=end))
if intersect:
cini, cend = intersect.ini, intersect.end
if comp.end > beyond:
cend = comp.end
if only_beyond:
cini = beyond
elif only_beyond:
continue
dsize += self.get_price_size(cini, cend)
# Extend billing point a little bit to benefit from a substantial discount
elif comp.end > beyond and (comp.end-comp.ini).days > 3*(comp.ini-beyond).days:
cend = comp.end
dsize += self.get_price_size(comp.ini, cend)
return dsize, cend
def get_register_or_renew_events(self, porders, ini, end):
counter = 0
for order in porders:
bu = getattr(order, 'new_billed_until', order.billed_until)
if bu:
registered = order.registered_on
if registered > ini and registered <= end:
counter += 1
if registered != bu and bu > ini and bu <= end:
counter += 1
if order.billed_until and order.billed_until != bu:
if registered != order.billed_until and order.billed_until > ini and order.billed_until <= end:
counter += 1
return counter
def bill_concurrent_orders(self, account, porders, rates, ini, end):
# Concurrent
# Get pricing orders
priced = {}
for ini, end, orders in helpers.get_chunks(porders, ini, end):
size = self.get_price_size(ini, end)
metric = len(orders)
interval = helpers.Interval(ini=ini, end=end)
for position, order in enumerate(orders, start=1):
csize = 0
compensations = getattr(order, '_compensations', [])
# Compensations < new_billed_until
for comp in compensations:
intersect = comp.intersect(interval)
if intersect:
csize += self.get_price_size(intersect.ini, intersect.end)
price = self.get_price(account, metric, position=position, rates=rates)
cprice = price * csize
price = price * size
if order in priced:
priced[order][0] += price
priced[order][1] += cprice
else:
priced[order] = [price, cprice]
lines = []
for order, prices in priced.items():
if hasattr(order, 'new_billed_until'):
discounts = ()
# Generate lines and discounts from order.nominal_price
price, cprice = prices
a = order.id
# Compensations > new_billed_until
dsize, new_end = self.apply_compensations(order, only_beyond=True)
cprice += dsize*price
if cprice:
discounts = (
(self._COMPENSATION, -cprice),
)
if new_end:
size = self.get_price_size(order.new_billed_until, new_end)
price += price*size
order.new_billed_until = new_end
line = self.generate_line(
order, price, ini, new_end or end, discounts=discounts, computed=True)
lines.append(line)
return lines
def bill_registered_or_renew_events(self, account, porders, rates):
# Before registration
lines = []
rdelta = self.get_pricing_rdelta()
if not rdelta:
raise NotImplementedError
for position, order in enumerate(porders, start=1):
if hasattr(order, 'new_billed_until'):
pend = order.billed_until or order.registered_on
pini = pend - rdelta
metric = self.get_register_or_renew_events(porders, pini, pend)
position = min(position, metric)
price = self.get_price(account, metric, position=position, rates=rates)
ini = order.billed_until or order.registered_on
end = order.new_billed_until
discounts = ()
dsize, new_end = self.apply_compensations(order)
if dsize:
discounts=(
(self._COMPENSATION, -dsize*price),
)
if new_end:
order.new_billed_until = new_end
end = new_end
line = self.generate_line(order, price, ini, end, discounts=discounts)
lines.append(line)
return lines
def bill_with_orders(self, orders, account, **options):
# For the "boundary conditions" just think that:
# date(2011, 1, 1) is equivalent to datetime(2011, 1, 1, 0, 0, 0)
# In most cases:
# ini >= registered_date, end < registered_date
# boundary lookup and exclude cancelled and billed
orders_ = []
bp = None
ini = datetime.date.max
end = datetime.date.min
for order in orders:
cini = order.registered_on
if order.billed_until:
# exclude cancelled and billed
if self.on_cancel != self.REFUND:
if order.cancelled_on and order.billed_until > order.cancelled_on:
continue
cini = order.billed_until
bp = self.get_billing_point(order, bp=bp, **options)
if order.billed_until and order.billed_until >= bp:
continue
order.new_billed_until = bp
ini = min(ini, cini)
end = max(end, bp)
orders_.append(order)
orders = orders_
# Compensation
related_orders = account.orders.filter(service=self.service)
if self.payment_style == self.PREPAY and self.on_cancel == self.COMPENSATE:
# Get orders pending for compensation
givers = list(related_orders.givers(ini, end))
givers = sorted(givers, key=cmp_to_key(helpers.cmp_billed_until_or_registered_on))
orders = sorted(orders, key=cmp_to_key(helpers.cmp_billed_until_or_registered_on))
self.assign_compensations(givers, orders, **options)
rates = self.get_rates(account)
has_billing_period = self.billing_period != self.NEVER
has_pricing_period = self.get_pricing_period() != self.NEVER
if rates and (has_billing_period or has_pricing_period):
concurrent = has_billing_period and not has_pricing_period
if not concurrent:
rdelta = self.get_pricing_rdelta()
ini -= rdelta
porders = related_orders.pricing_orders(ini, end)
porders = list(set(orders).union(set(porders)))
porders = sorted(porders, key=cmp_to_key(helpers.cmp_billed_until_or_registered_on))
if concurrent:
# Periodic billing with no pricing period
lines = self.bill_concurrent_orders(account, porders, rates, ini, end)
else:
# Periodic and one-time billing with pricing period
lines = self.bill_registered_or_renew_events(account, porders, rates)
else:
# No rates optimization or one-time billing without pricing period
lines = []
price = self.nominal_price
# Calculate nominal price
for order in orders:
ini = order.billed_until or order.registered_on
end = order.new_billed_until
discounts = ()
dsize, new_end = self.apply_compensations(order)
if dsize:
discounts=(
(self._COMPENSATION, -dsize*price),
)
if new_end:
order.new_billed_until = new_end
end = new_end
line = self.generate_line(order, price, ini, end, discounts=discounts)
lines.append(line)
return lines
def bill_with_metric(self, orders, account, **options):
lines = []
bp = None
for order in orders:
prepay_discount = 0
bp = self.get_billing_point(order, bp=bp, **options)
if (self.billing_period != self.NEVER and
self.get_pricing_period() == self.NEVER and
self.payment_style == self.PREPAY and order.billed_on):
# Recharge
if self.payment_style == self.PREPAY and order.billed_on:
recharges = []
rini = order.billed_on
rend = min(bp, order.billed_until)
bmetric = order.billed_metric
if bmetric is None:
bmetric = order.get_metric(order.billed_on)
bsize = self.get_price_size(rini, order.billed_until)
prepay_discount = self.get_price(account, bmetric) * bsize
prepay_discount = round(prepay_discount, 2)
for cini, cend, metric in order.get_metric(rini, rend, changes=True):
size = self.get_price_size(cini, cend)
price = self.get_price(account, metric) * size
discounts = ()
discount = min(price, max(prepay_discount, 0))
prepay_discount -= price
if discount > 0:
price -= discount
discounts = (
(self._PREPAY, -discount),
)
# Don't overdload bills with lots of lines
if price > 0:
recharges.append((order, price, cini, cend, metric, discounts))
if prepay_discount < 0:
# User has prepaid less than the actual consumption
for order, price, cini, cend, metric, discounts in recharges:
if discounts:
price -= discounts[0][1]
line = self.generate_line(order, price, cini, cend, metric=metric,
computed=True, discounts=discounts)
lines.append(line)
if order.billed_until and order.cancelled_on and order.cancelled_on >= order.billed_until:
# Cancelled order
continue
if self.billing_period != self.NEVER:
ini = order.billed_until or order.registered_on
# Periodic billing
if bp <= ini:
# Already billed
continue
order.new_billed_until = bp
if self.get_pricing_period() == self.NEVER:
# Changes (Mailbox disk-like)
for cini, cend, metric in order.get_metric(ini, bp, changes=True):
price = self.get_price(account, metric)
discounts = ()
# Since the current datamodel can't guarantee to retrieve the exact
# state for calculating prepay_discount (service price could have change)
# maybe is it better not to discount anything.
# discount = min(price, max(prepay_discount, 0))
# if discount > 0:
# price -= discount
# prepay_discount -= discount
# discounts = (
# (self._PREPAY', -discount),
# )
if metric > 0:
line = self.generate_line(order, price, cini, cend, metric=metric,
discounts=discounts)
lines.append(line)
elif self.get_pricing_period() == self.billing_period:
# pricing_slots (Traffic-like)
if self.payment_style == self.PREPAY:
raise NotImplementedError
for cini, cend in self.get_pricing_slots(ini, bp):
metric = order.get_metric(cini, cend)
price = self.get_price(account, metric)
discounts = ()
# discount = min(price, max(prepay_discount, 0))
# if discount > 0:
# price -= discount
# prepay_discount -= discount
# discounts = (
# (self._PREPAY, -discount),
# )
if metric > 0:
line = self.generate_line(order, price, cini, cend, metric=metric,
discounts=discounts)
lines.append(line)
elif self.get_pricing_period() in (self.MONTHLY, self.ANUAL):
if self.payment_style == self.PREPAY:
# Traffic Prepay
metric = order.get_metric(timezone.now().date())
if metric > 0:
price = self.get_price(account, metric)
for cini, cend in self.get_pricing_slots(ini, bp):
line = self.generate_line(order, price, cini, cend, metric=metric)
lines.append(line)
else:
raise NotImplementedError
else:
raise NotImplementedError
else:
# One-time billing
if order.billed_until:
continue
date = timezone.now().date()
order.new_billed_until = date
if self.get_pricing_period() == self.NEVER:
# get metric (Job-like)
metric = order.get_metric(date)
price = self.get_price(account, metric)
line = self.generate_line(order, price, date, metric=metric)
lines.append(line)
else:
raise NotImplementedError
# Last processed metric for futrue recharges
order.new_billed_metric = metric
return lines
def generate_bill_lines(self, orders, account, **options):
if options.get('proforma', False):
options['commit'] = False
if not self.metric:
lines = self.bill_with_orders(orders, account, **options)
else:
lines = self.bill_with_metric(orders, account, **options)
if options.get('commit', True):
now = timezone.now().date()
for line in lines:
order = line.order
order.billed_on = now
order.billed_metric = getattr(order, 'new_billed_metric', order.billed_metric)
order.billed_until = getattr(order, 'new_billed_until', order.billed_until)
order.save(update_fields=('billed_on', 'billed_until', 'billed_metric'))
return lines