我正在尝试解决“DoesNotExist错误”的问题,我已经尝试找到正确的方法来处理没有答案的结果,但是我仍然遇到了“DoesNotExist”或“Object hast not Attribute DoestNotExists”的问题。
from django.http import HttpResponse
from django.contrib.sites.models import Site
from django.utils import simplejson
from vehicles.models import *
from gpstracking.models import *
def request_statuses(request):
data = []
vehicles = Vehicle.objects.filter()
Vehicle.vehicledevice_
for vehicle in vehicles:
try:
vehicledevice = vehicle.vehicledevice_set.get(is_joined__exact = True)
imei = vehicledevice.device.imei
try:
lastposition = vehicledevice.device.devicetrack_set.latest('date_time_process')
altitude = lastposition.altitude
latitude = lastposition.latitude
longitude = lastposition.longitude
date_time_process = lastposition.date_time_process.strftime("%Y-%m-%d %H:%M:%S"),
date_time_created = lastposition.created.strftime("%Y-%m-%d %H:%M:%S")
except Vehicle.vehicledevice.device.DoesNotExist:
lastposition = None
altitude = None
latitude = None
longitude = None
date_time_process = None
date_time_created = None
except Vehicle.DoesNotExist:
vehicledevice = None
imei = ''
item = [
vehicle.vehicle_type.name,
imei,
altitude,
"Lat %s Lng %s" % (latitude, longitude),
date_time_process,
date_time_created,
'',
''
]
data.append(item)
statuses = {
"sEcho": 1,
"iTotalRecords": vehicles.count(),
"iTotalDisplayRecords": vehicles.count(),
"aaData": data
}
json = simplejson.dumps(statuses)
return HttpResponse(json, mimetype='application/json')