django-orchestra/orchestra/apps/resources/helpers.py
2014-10-27 13:29:02 +00:00

65 lines
2.8 KiB
Python

import datetime
from django.contrib.contenttypes.models import ContentType
from django.db.models.loading import get_model
from django.utils import timezone
from orchestra.models.utils import get_model_field_path
from .backends import ServiceMonitor
def compute_resource_usage(data):
""" Computes MonitorData.used based on related monitors """
from .models import MonitorData
resource = data.resource
today = timezone.now()
result = 0
has_result = False
for monitor in resource.monitors:
# Get related dataset
resource_model = data.content_type.model_class()
monitor_model = get_model(ServiceMonitor.get_backend(monitor).model)
if resource_model == monitor_model:
dataset = MonitorData.objects.filter(monitor=monitor,
content_type=data.content_type_id, object_id=data.object_id)
else:
path = get_model_field_path(monitor_model, resource_model)
fields = '__'.join(path)
objects = monitor_model.objects.filter(**{fields: data.object_id})
pks = objects.values_list('id', flat=True)
ct = ContentType.objects.get_for_model(monitor_model)
dataset = MonitorData.objects.filter(monitor=monitor, content_type=ct, object_id__in=pks)
# Process dataset according to resource.period
if resource.period == resource.MONTHLY_AVG:
try:
last = dataset.latest()
except MonitorData.DoesNotExist:
continue
has_result = True
epoch = datetime(year=today.year, month=today.month, day=1, tzinfo=timezone.utc)
total = (last.created_at-epoch).total_seconds()
dataset = dataset.filter(created_at__year=today.year, created_at__month=today.month)
ini = epoch
for data in dataset:
slot = (data.created_at-ini).total_seconds()
result += data.value * slot/total
ini = data.created_at
elif resource.period == resource.MONTHLY_SUM:
dataset = dataset.filter(created_at__year=today.year, created_at__month=today.month)
# FIXME Aggregation of 0s returns None! django bug?
# value = dataset.aggregate(models.Sum('value'))['value__sum']
values = dataset.values_list('value', flat=True)
if values:
has_result = True
result += sum(values)
elif resource.period == resource.LAST:
try:
result += dataset.latest().value
except MonitorData.DoesNotExist:
continue
has_result = True
else:
raise NotImplementedError("%s support not implemented" % data.period)
return float(result)/resource.get_scale() if has_result else None