GCP ADC Check

check_gcp_adc_status.py

"""
GCP ADC ( Application Default Credentials ) Authentication Check Module

This module handles the checking responsibility
    of weather ADC is setup for the project or not .
   
Test:
    python3 -m gcp_authenticate
"""
import os
import google.auth
from google.auth.exceptions import DefaultCredentialsError
from typing import Optional, Callable

def check_gcp_adc_status(logger: Optional[Callable]=None, log_console: bool=False):
    """Checks if Application Default Credentials are available and valid.
    
    args:
        logger (Optional[Callable]) : a callback that does the logging according to you .
        log_console (bool) : if print on stdot/console needed .
    """
    try:
        # Attempt to find the default credentials
        credentials, project = google.auth.default()

        _msg1 = f"""ADC found.
        Project ID: {project}
        """
        def do_logging(msg: str, level: str = 'info'):
            if logger:
                logger(msg, level=level)
            if log_console:
                print(msg)
        
        do_logging(_msg1)

        # Optional: You can check details about the credentials found
        if hasattr(credentials, "service_account_email"):
            _msg2=f"ADC Credential type: Service Account ({credentials.service_account_email})"
            do_logging(_msg2)
            
        elif hasattr(credentials, "quota_project"):
            _msg2=f"ADC Credential type: User Account (Quota Project: {credentials.quota_project})"
            do_logging(_msg2)
        else:
            _msg2="ADC Credential type: Unknown/Other"
            do_logging(_msg2)
            
        return True

    except DefaultCredentialsError as e:
        _msg3="ADC is not configured"
        do_logging(_msg3)
        return False
    except Exception as e:
        do_logging(f"An unexpected error occurred while checking ADC: {e}", 'debug')
        return False

if __name__ == '__main__':
    # Run the check
    if check_gcp_adc_status() or 'GOOGLE_APPLICATION_CREDENTIALS' in os.environ:
        # You can now confidently use other GCP client libraries
        print("\nProceeding with GCP client library operations.")
    else:
        print("\nPlease run `gcloud auth application-default login` or set the GOOGLE_APPLICATION_CREDENTIALS environment variable.")

sample_usage.py

# entrypoint of your project
"""
This is the sample of using in your project.

- If ADC is not set , fallback to service account .
"""
import os

PATH_TO_SERVICE_ACCOUNT_FILE = 'mounted/location/of/service/account/file/in/your/machine/file.json'
if check_gcp_adc_status(logger = lambda msg, **kwargs: log.info(msg)) or 'GOOGLE_APPLICATION_CREDENTIALS' in os.environ:
    # You can now confidently use other GCP client libraries
    log.info("GCP Autentication Found . Proceed with GCP client library operations.")
elif os.path.exists(PATH_TO_SERVICE_ACCOUNT_FILE):
    os.environ["GOOGLE_APPLICATION_CREDENTIALS"] = str(PATH_TO_SERVICE_ACCOUNT_FILE)
    log.info("GCP Service Account File Set . Proceed with GCP client library operations.")
else:
    raise Exception("Please run `gcloud auth application-default login` or set the GOOGLE_APPLICATION_CREDENTIALS environment variable.")