如何从Python脚本上传Google Cloud Storage上的字节图像

Question

I want to upload an image on Google Cloud Storage from a python script. This is my code:

from oauth2client.service_account import ServiceAccountCredentials
from googleapiclient import discovery

scopes = ['https://www.googleapis.com/auth/devstorage.full_control']
credentials = ServiceAccountCredentials.from_json_keyfile_name('serviceAccount.json', scop
es)
service = discovery.build('storage','v1',credentials = credentials)

body = {'name':'my_image.jpg'}

req = service.objects().insert(
   bucket='my_bucket', body=body,
   media_body=googleapiclient.http.MediaIoBaseUpload(
      gcs_image, 'application/octet-stream'))

resp = req.execute()

if gcs_image = open('img.jpg', 'r') the code works and correctly save my image on Cloud Storage. How can I directly upload a bytes image? (for example from an OpenCV/Numpy array: gcs_image = cv2.imread('img.jpg') )

Answer 1

If you want to upload your image from file.

import os
from google.cloud import storage

def upload_file_to_gcs(bucket_name, local_path, local_file_name, target_key):
    try:
        client = storage.Client()
        bucket = client.bucket(bucket_name)
        full_file_path = os.path.join(local_path, local_file_name)
        bucket.blob(target_key).upload_from_filename(full_file_path)
        return bucket.blob(target_key).public_url

    except Exception as e:
        print(e)

    return None

but if you want to upload bytes directly:

import os
from google.cloud import storage

def upload_data_to_gcs(bucket_name, data, target_key):
    try:
        client = storage.Client()
        bucket = client.bucket(bucket_name)
        bucket.blob(target_key).upload_from_string(data)
        return bucket.blob(target_key).public_url

    except Exception as e:
        print(e)

    return None

note that target_key is prefix and the name of the uploaded file.

Answer 2

MediaIoBaseUpload expects an io.Base -like object and raises following error:

  'numpy.ndarray' object has no attribute 'seek'

upon receiving a ndarray object. To solve it I am using TemporaryFile and numpy.ndarray().tofile()

from oauth2client.service_account import ServiceAccountCredentials
from googleapiclient import discovery
import googleapiclient
import numpy as np
import cv2
from tempfile import TemporaryFile


scopes = ['https://www.googleapis.com/auth/devstorage.full_control']
credentials = ServiceAccountCredentials.from_json_keyfile_name('serviceAccount.json', scopes)
service = discovery.build('storage','v1',credentials = credentials)

body = {'name':'my_image.jpg'}
with TemporaryFile() as gcs_image:
    cv2.imread('img.jpg').tofile(gcs_image)
    req = service.objects().insert(
       bucket='my_bucket’, body=body,
       media_body=googleapiclient.http.MediaIoBaseUpload(
          gcs_image, 'application/octet-stream'))

    resp = req.execute()

Be aware that googleapiclient is non-idiomatic and maintenance only (it's not developed anymore). I would recommend using idiomatic one .

Answer 3

In my case, I wanted to upload a PDF document to Cloud Storage from bytes.

When I tried the below, it created a text file with my byte string in it.

blob.upload_from_string(bytedata)

In order to create an actual PDF file using the byte string I had to do:

blob.upload_from_string(bytedata, content_type='application/pdf')

My byte data was b64encoded, so I also had b64decode it first.