def AssignDrink(self, drink, user):
"""Assigns, or re-assigns, a previously-recorded Drink.
Statistics and session data will be recomputed as a side-effect
of any change to user assignment. (If the drink is already assigned
to the given user, this method is a no-op).
Args:
drink: The Drink object (or drink id) to assign.
user: The User object (or username) to set as the owner,
or None for anonymous.
Returns:
The drink.
"""
drink = get_drink(drink)
if drink.user == user:
return drink
stats.invalidate(drink)
drink.user = user
drink.save()
stats.generate(drink)
self.cache.update_generation()
return drink
def SetDrinkVolume(self, drink, volume_ml):
"""Updates the drink volume."""
if volume_ml == drink.volume_ml:
return
drink.volume_ml = volume_ml
drink.save()
stats.invalidate(drink)
drink.session.Rebuild()
stats.generate(drink)
def handle(self, **options):
stats.invalidate_all()
drinks = models.Drink.objects.all().order_by('id')
num_drinks = len(drinks)
pos = 0
for d in drinks:
pos += 1
progbar('regenerating stats', pos, num_drinks)
stats.generate(d, invalidate_first=False)
print ''
print 'done!'
def handle(self, **options):
stats.invalidate(None)
drinks = models.Drink.objects.all().order_by('id')
num_drinks = len(drinks)
pos = 0
for d in drinks:
pos += 1
progbar('regenerating stats', pos, num_drinks)
stats.generate(d, invalidate_first=False)
print ''
print 'done!'
def CancelDrink(self, drink, spilled=False):
"""Permanently deletes a Drink from the system.
Associated data, such as SystemEvent, PourPicture, and other data, will
be destroyed along with the drink. Statistics and session data will be
recomputed after the drink is destroyed.
Args:
drink_id: The Drink, or id of the Drink, to cancel.
spilled: If True, after canceling the Drink, the drink's volume will
be added to its Keg's "spilled" total. This is is typically useful
for removing test pours from the system while still accounting for
the lost volume.
Returns:
The deleted drink.
"""
if not isinstance(drink, models.Drink):
drink = models.Drink.objects.get(id=drink)
session = drink.session
drink_id = drink.id
keg = drink.keg
volume_ml = drink.volume_ml
keg_update_fields = ['served_volume_ml']
keg.served_volume_ml -= volume_ml
# Transfer volume to spillage if requested.
if spilled and volume_ml and drink.keg:
keg.spilled_ml += volume_ml
keg_update_fields.append('spilled_ml')
keg.save(update_fields=keg_update_fields)
# Invalidate all statistics.
stats.invalidate(drink)
# Delete the drink, including any objects related to it.
drink.delete()
session.Rebuild()
# Regenerate stats for any drinks following the just-deleted one.
for drink in models.Drink.objects.filter(
id__gt=drink_id).order_by('id'):
stats.generate(drink)
self.cache.update_generation()
return drink
def cancel_drink(self, drink, spilled=False):
"""Permanently deletes a Drink from the system.
Associated data, such as SystemEvent, PourPicture, and other data, will
be destroyed along with the drink. Statistics and session data will be
recomputed after the drink is destroyed.
Args:
drink_id: The Drink, or id of the Drink, to cancel.
spilled: If True, after canceling the Drink, the drink's volume will
be added to its Keg's "spilled" total. This is is typically useful
for removing test pours from the system while still accounting for
the lost volume.
Returns:
The deleted drink.
"""
if not isinstance(drink, models.Drink):
drink = models.Drink.objects.get(id=drink)
session = drink.session
drink_id = drink.id
keg = drink.keg
volume_ml = drink.volume_ml
keg_update_fields = ['served_volume_ml']
keg.served_volume_ml -= volume_ml
# Transfer volume to spillage if requested.
if spilled and volume_ml and drink.keg:
keg.spilled_ml += volume_ml
keg_update_fields.append('spilled_ml')
keg.save(update_fields=keg_update_fields)
# Invalidate all statistics.
stats.invalidate(drink)
# Delete the drink, including any objects related to it.
drink.delete()
session.Rebuild()
# Regenerate stats for any drinks following the just-deleted one.
for drink in models.Drink.objects.filter(id__gt=drink_id).order_by('id'):
stats.generate(drink)
self.cache.update_generation()
return drink
def set_drink_volume(self, drink, volume_ml):
"""Updates the drink volume."""
if volume_ml == drink.volume_ml:
return
difference = volume_ml - drink.volume_ml
drink.volume_ml = volume_ml
drink.save(update_fields=['volume_ml'])
keg = drink.keg
keg.served_volume_ml += difference
keg.save(update_fields=['served_volume_ml'])
stats.invalidate(drink)
drink.session.Rebuild()
# Regenerate stats for this drink and all subsequent.
for drink in models.Drink.objects.filter(id__gte=drink.id).order_by('id'):
stats.generate(drink)
self.cache.update_generation()
def SetDrinkVolume(self, drink, volume_ml):
"""Updates the drink volume."""
if volume_ml == drink.volume_ml:
return
difference = volume_ml - drink.volume_ml
drink.volume_ml = volume_ml
drink.save(update_fields=['volume_ml'])
keg = drink.keg
keg.served_volume_ml += difference
keg.save(update_fields=['served_volume_ml'])
stats.invalidate(drink)
drink.session.Rebuild()
# Regenerate stats for this drink and all subsequent.
for drink in models.Drink.objects.filter(
id__gte=drink.id).order_by('id'):
stats.generate(drink)
self.cache.update_generation()
def AssignDrink(self, drink, user):
"""Assigns, or re-assigns, a previously-recorded Drink.
Statistics and session data will be recomputed as a side-effect
of any change to user assignment. (If the drink is already assigned
to the given user, this method is a no-op).
Args:
drink: The Drink object (or drink id) to assign.
user: The User object (or username) to set as the owner,
or None for anonymous.
Returns:
The drink.
"""
drink = get_drink(drink)
user = get_user(user)
if drink.user == user:
return drink
drink.user = user
drink.save()
stats.invalidate(drink)
for e in drink.events.all():
e.user = user
e.save()
for p in drink.pictures.all():
p.user = user
p.save()
drink.session.Rebuild()
stats.generate(drink)
self.cache.update_generation()
return drink
class KegbotBackend:
"""Provides high-level operations against the Kegbot system."""
def __init__(self):
self._logger = logging.getLogger('backend')
self.cache = KegbotCache()
@transaction.commit_on_success
def CreateNewUser(self, username):
"""Creates and returns a User for the given username."""
return models.User.objects.create(username=username)
@transaction.commit_on_success
def CreateTap(self, name, meter_name, relay_name=None, ml_per_tick=None):
"""Creates and returns a new KegTap.
Args:
name: The human-meaningful name for the tap, for instance, "Main Tap".
meter_name: The unique sensor name for the tap, for instance,
"kegboard.flow0".
relay_name: If the tap is connected to a relay, this specifies its
name, for instance, "kegboard.relay0".
ml_per_tick: The number of milliliters per flow meter tick on this
tap's meter.
Returns:
The new KegTap instance.
"""
tap = models.KegTap.objects.create(name=name,
meter_name=meter_name,
relay_name=relay_name,
ml_per_tick=ml_per_tick)
tap.save()
return tap
@transaction.commit_on_success
def CreateAuthToken(self, auth_device, token_value, username=None):
"""Creates a new AuthenticationToken.
The combination of (auth_device, token_value) must be unique within the
system.
Args:
auth_device: The name of the authentication device, for instance,
"core.rfid".
token_value: The opaque string value of the token, which is typically
unique within the `auth_device` namespace.
username: The User with which to associate this Token.
Returns:
The newly-created AuthenticationToken.
"""
token = models.AuthenticationToken.objects.create(
auth_device=auth_device, token_value=token_value)
if username:
user = get_user(username)
token.user = user
token.save()
return token
@transaction.commit_on_success
def RecordDrink(self,
tap_name,
ticks,
volume_ml=None,
username=None,
pour_time=None,
duration=0,
shout='',
tick_time_series='',
do_postprocess=True):
"""Records a new drink against a given tap.
The tap must have a Keg assigned to it (KegTap.current_keg), and the keg
must be active.
Args:
tap_name: The tap's meter_name.
ticks: The number of ticks observed by the flow sensor for this drink.
volume_ml: The volume, in milliliters, of the pour. If specifed, this
value is saved as the Drink's actual value. If not specified, a
volume is computed based on `ticks` and the KegTap's
`ml_per_tick` setting.
username: The username with which to associate this Drink, or None for
an anonymous Drink.
pour_time: The datetime of the drink. If not supplied, the current
date and time will be used.
duration: Number of seconds it took to pour this Drink. This is
optional information not critical to the record.
shout: A short comment left by the user about this Drink. Optional.
tick_time_series: Vector of flow update data, used for diagnostic
purposes.
do_postprocess: Set to False during bulk inserts.
Returns:
The newly-created Drink instance.
"""
tap = self._GetTapFromName(tap_name)
if not tap:
raise BackendError("Tap unknown")
if not tap.is_active or not tap.current_keg:
raise BackendError("No active keg at this tap")
if volume_ml is None:
volume_ml = float(ticks) * tap.ml_per_tick
user = None
if username:
user = get_user(username)
else:
user = models.SiteSettings.get().default_user
if not pour_time:
pour_time = timezone.now()
keg = tap.current_keg
if tick_time_series:
try:
# Validate the time series by parsing it; canonicalize it by generating
# it again. If malformed, just junk it; it's non-essential information.
tick_time_series = time_series.to_string(
time_series.from_string(tick_time_series))
except ValueError, e:
self._logger.warning(
'Time series invalid, ignoring. Error was: %s' % e)
tick_time_series = ''
d = models.Drink(ticks=ticks,
keg=keg,
user=user,
volume_ml=volume_ml,
time=pour_time,
duration=duration,
shout=shout,
tick_time_series=tick_time_series)
models.DrinkingSession.AssignSessionForDrink(d)
d.save()
keg.served_volume_ml += volume_ml
keg.save(update_fields=['served_volume_ml'])
self.cache.update_generation()
if do_postprocess:
stats.generate(d)
events = models.SystemEvent.ProcessDrink(d)
tasks.schedule_tasks(events)
return d
