GCP Presigned URL bucket

README.md

GCS Signed URL Generator

This Python script generates a signed URL for downloading a blob from Google Cloud Storage (GCS). The signed URL allows users to access the blob without requiring authentication.

Prerequisites

• Python >= 3.10.x
• Google Service Account

How to Use

$ export GOOGLE_APPLICATION_CREDENTIALS="/path/to/your/service-account-file.json"
$ python3 gcs-sign.py -h
usage: gcs-sign.py [-h] -b BUCKET_NAME -o BLOB_NAME -e EXPIRATION

Generate a signed URL for a Google Cloud Storage blob.

options:
  -h, --help            show this help message and exit
  -b BUCKET_NAME, --bucket-name BUCKET_NAME
                        The name of the GCS bucket
  -o BLOB_NAME, --blob-name BLOB_NAME
                        The name of the blob in the bucket
  -e EXPIRATION, --expiration EXPIRATION
                        The expiration time in minutes for the signed URL

gcs-sign.py

import datetime
import argparse
import logging

from google.cloud import storage

# Set up logging
logging.basicConfig(level=logging.INFO)

def generate_download_signed_url_v4(bucket_name: str, blob_name: str, expiration_minutes: int) -> str:
    """Generates a v4 signed URL for downloading a blob."""
    try:
        storage_client = storage.Client()
        bucket = storage_client.bucket(bucket_name)
        blob = bucket.blob(blob_name)

        url = blob.generate_signed_url(
            version="v4",
            expiration=datetime.timedelta(minutes=expiration_minutes),
            method="GET",
        )

        logging.info("Generated GET signed URL: %s", url)
        return url
    except Exception as e:
        logging.error("Error generating signed URL: %s", e)
        raise

if __name__ == "__main__":
    parser = argparse.ArgumentParser(description='Generate a signed URL for a Google Cloud Storage blob.')
    parser.add_argument('-b', '--bucket-name', type=str, required=True, help='The name of the GCS bucket')
    parser.add_argument('-o', '--blob-name', type=str, required=True, help='The name of the blob in the bucket')
    parser.add_argument('-e', '--expiration', type=int, required=True, help='The expiration time in minutes for the signed URL')
    
    args = parser.parse_args()

    # Set logging level based on the verbose flag or log-level flag
    if args.verbose:
        logging.basicConfig(level=logging.DEBUG)
    else:
        logging.basicConfig(level=args.log_level)

    url = generate_download_signed_url_v4(args.bucket_name, args.blob_name, args.expiration)

    print(url)
    

requirements.txt

google-cloud-storage==2.19.0