def start_download(self, device, request, done):
"""
This is called to request downloading a specified image into
the standby partition of a device based on a NBI call.
:param device: A Voltha.Device object.
:param request: A Voltha.ImageDownload object.
:param done: (Deferred) Deferred to fire when done
:return: (Deferred) Shall be fired to acknowledge the download.
"""
log.info('image_download', request=request)
try:
if request.name in self._downloads:
raise Exception("Download request with name '{}' already exists".
format(request.name))
try:
download = Download.create(self, request, self._download_protocols)
except Exception:
request.additional_info = 'Download request creation failed due to exception'
raise
try:
self._downloads[download.name] = download
self._update_download_status(request, download)
done.callback('started')
return done
except Exception:
request.additional_info = 'Download request startup failed due to exception'
del self._downloads[download.name]
download.cancel_download(request)
raise
except Exception as e:
self.log.exception('create', e=e)
request.reason = ImageDownload.UNKNOWN_ERROR
request.state = ImageDownload.DOWNLOAD_FAILED
if not request.additional_info:
request.additional_info = e.message
self.adapter_agent.update_image_download(request)
# restore admin state to enabled
device.admin_state = AdminState.ENABLED
self.adapter_agent.update_device(device)
raise
