ERROR: blob.download_to_filename, return an empty file and raise error - google-cloud-storage

Question

I'm trying to download the *.tflite model on Google Cloud Storage to my Rapberry Pi 3B+ using the code as follows:
export_metadata = response.metadata
export_directory = export_metadata.export_model_details.output_info.gcs_output_directory
model_dir_remote = export_directory + remote_model_filename # file path on Google Cloud Storage
model_dir = os.path.join("models", model_filename) # file path supposed to store locally
blob = bucket.blob(model_dir_remote)
blob.download_to_filename(model_dir)
However, this returns an empty file in my target directory locally, and meanwhile, raise an error:
# ERROR: google.resumable_media.common.InvalidResponse: ('Request failed with status code', 404,
# 'Expected one of', <HTTPStatus.OK: 200>, <HTTPStatus.PARTIAL_CONTENT: 206>)
# ERROR: google.api_core.exceptions.NotFound: 404
# GET https://storage.googleapis.com/download/storage/v1/b/ao-example/o/
# gs%3A%2F%2Fao-example%2Fmodel-export%2Ficn%2Fedgetpu_tflite-Test_Model12-2020-11-16T07%3A54%3A27.187Z%2Fedgetpu_model.tflite?alt=media:
# ('Request failed with status code', 404, 'Expected one of', <HTTPStatus.OK: 200>, <HTTPStatus.PARTIAL_CONTENT: 206>)
I guaranteed the corresponding authority to the service account. What confuses me is that when I use gsutil command, it works:
gsutil cp gs://ao-example/model-export/icn/edgetpu_model.tflite models/
Is anyone encountering the same problem? Is there any error in my code? Your help will be greatly appreciated!
I used the following code:
from google.cloud import storage
from google.cloud import automl
from google.cloud.storage import Blob
client = storage.Client(project="semesterproject-294707")
bucket_name = 'ao-example'
bucket = client.get_bucket(bucket_name)
model_dir_remote = "gs://ao-example/model-export/icn/edgetpu_tflite-Test_Model13-2020-11-18T15:03:42.620Z/edgetpu_model.tflite"
blob = Blob(model_dir_remote, bucket)
with open("models/edgetpu_model13.tflite", "wb") as file_obj:
blob.download_to_file(file_obj)
This raises the same error, and return an empty file also... Still, I can use gsutil cp command to download the file...
(Edited on 06/12/2020)
The info of model generated:
export_model_details {
output_info {
gcs_output_directory: "gs://ao-example/model-export/icn/edgetpu_tflite-gc14-2020-12-06T14:43:18.772911Z/"
}
}
model_gcs_path: 'gs://ao-example/model-export/icn/edgetpu_tflite-gc14-2020-12-06T14:43:18.772911Z/edgetpu_model.tflite'
model_local_path: 'models/edgetpu_model.tflite'
It still encounters the error:
google.api_core.exceptions.NotFound: 404 GET https://storage.googleapis.com/download/storage/v1/b/ao-example/o/gs%3A%2F%2Fao-example%2Fmodel-export%2Ficn%2Fedgetpu_tflite-gc14-2020-12-06T14%3A43%3A18.772911Z%2Fedgetpu_model.tflite?alt=media: ('Request failed with status code', 404, 'Expected one of', <HTTPStatus.OK: 200>, <HTTPStatus.PARTIAL_CONTENT: 206>)
Still, when I use gsutil cp command, it works:
gsutil cp model_gcs_path model_local_path
Edited on 12/12/2020
Soni Sol's method works! Thanks!!

Answer 1

I believe you should use something like this:
from google.cloud.storage import Blob
client = storage.Client(project="my-project")
bucket = client.get_bucket("my-bucket")
blob = Blob("file_on_gcs", bucket)
with open("/tmp/file_on_premise", "wb") as file_obj:
blob.download_to_file(file_obj)
Blobs / Objects

Answer 2

When using the client libraries the gs:// is not needed, also the name of the bucket is being passed twice on This Question they had a similar issue and got corrected.
please try with the following code:
from google.cloud import storage
from google.cloud import automl
from google.cloud.storage import Blob
client = storage.Client(project="semesterproject-294707")
bucket_name = 'ao-example'
bucket = client.get_bucket(bucket_name)
model_dir_remote = "model-export/icn/edgetpu_tflite-Test_Model13-2020-11-18T15:03:42.620Z/edgetpu_model.tflite"
blob = Blob(model_dir_remote, bucket)
with open("models/edgetpu_model13.tflite", "wb") as file_obj:
blob.download_to_file(file_obj)