Google Cloud authorization keeps failing with Python 3 - Type is None, expected one of ('authorized_user', 'service_account') - google-cloud-storage

Question

I am trying to download a file for the first time from Google Cloud Storage.
I set the path to the googstruct.json service account key file that I downloaded from https://cloud.google.com/storage/docs/reference/libraries#client-libraries-usage-python
Do need to set the authorization to Google Cloud outside the code somehow? Or is there a better "How to use Google Cloud Storage" then the one on the google site?
It seems like I am passing the wrong type to the storage_client = storage.Client()
the exception string is below.
Exception has occurred: google.auth.exceptions.DefaultCredentialsError
The file C:\Users\Cary\Documents\Programming\Python\QGIS\GoogleCloud\googstruct.json does not have a valid type.
Type is None, expected one of ('authorized_user', 'service_account').
MY PYTHON 3.7 CODE
from google.cloud import storage
import os
os.environ["GOOGLE_APPLICATION_CREDENTIALS"]="C:\\GoogleCloud\\googstruct.json"
# Instantiates a client
storage_client = storage.Client()
bucket_name = 'structure_ssi'
destination_file_name = "C:\\Users\\18809_PIPEM.shp"
source_blob_name = '18809_PIPEM.shp'
download_blob(bucket_name, source_blob_name, destination_file_name)
def download_blob(bucket_name, source_blob_name, destination_file_name):
"""Downloads a blob from the bucket."""
storage_client = storage.Client()
bucket = storage_client.get_bucket(bucket_name)
blob = bucket.blob(source_blob_name)
blob.download_to_filename(destination_file_name)
print('Blob {} downloaded to {}.'.format(
source_blob_name,
destination_file_name
)
)
I did look at this but I cannot tell if this is my issue. I have tried both.
('Unexpected credentials type', None, 'Expected', 'service_account') with oauth2client (Python)

Answer 1

This error means that the Json Service Account Credentials that you are trying to use C:\\GoogleCloud\\googstruct.json are corrupt or the wrong type.
The first (or second) line in the file googstruct.json should be "type": "service_account".
Another few items to improve your code:
You do not need to use \\, just use / to make your code easier
and cleaner to read.
Load your credentials directly and do not modify environment
variables:
storage_client = storage.Client.from_service_account_json('C:/GoogleCloud/googstruct.json')
Wrap API calls in try / except. Stack traces do not impress customers. It is better to have clear, simple, easy to read error messages.