+ def get_booking_utilization(self, weeks):
+ """
+ Return a dictionary containing the count of booked and free seconds for a resource in the
+ range [now,now + weeks] if weeks is positive,
+ or [now-weeks, now] if weeks is negative
+ """
+
+ length = timedelta(weeks=abs(weeks))
+ now = timezone.now()
+
+ start = now
+ end = now + length
+ if weeks < 0:
+ start = now - length
+ end = now
+
+ bookings = self.booking_set.filter(start__lt=start + length, end__gt=start)
+
+ booked_seconds = 0
+ for booking in bookings:
+ booking_start = booking.start
+ booking_end = booking.end
+ if booking_start < start:
+ booking_start = start
+ if booking_end > end:
+ booking_end = start + length
+ total = booking_end - booking_start
+ booked_seconds += total.total_seconds()
+
+ return {'booked_seconds': booked_seconds,
+ 'available_seconds': length.total_seconds() - booked_seconds}
+