Boto3: AttributeError: 'S3' object has no attribute 'download_fileobj'

[MattBlack85]

I'm trying to use the download_obj feature but it seems that is not injected correctly into the client. I tried with the example from the documentation and from tests but I had no luck. download_file works as expected

[JordonPhillips]

That is a currently unreleased feature. It will be available in the next minor version of boto3. Please check out the stable dos to only see features which have been pushed out in a release.

[Kartoshka548]

def download(self, filename, fileobj=None, bucket=settings.AWS_BUCKET):
    '''
    If fileobj is passed, use it to store data coming from AWS.
    Do not return (mutable object was already passed).
        - Exempli gratia,
            with BytesIO() as fileobj:
                <S3CONNECTION>.download(filename, fileobj)
    Otherwise, return new, in-memory filelike object and rely on gc
        - Exempli gratia,
        fileobj = <S3CONNECTION>.download(filename)

    from io import BytesIO
    f = fileobj or BytesIO()
    '''
    try:
        try:
            # inject the data into exiting or new, just created object
            self.download_fileobj(bucket, filename, f)
        except AttributeError:
            # download the data into temp file
            # copy downloaded content into fileobj
            # remove temp file
            _file = os.path.join(settings.FILE_LOCATION, filename)
            self.download_file(bucket, filename, _file)
            with open(_file, 'rb') as file_:
                f.write(file_.read())
            os.remove(_file)
    except exceptions.ClientError:
        raise CustomException("File not found")
    f.seek(0)
    if not fileobj: return f

[ns-cweber]

I'm seeing the same thing on 1.7.62 even though the docs say it should exist: https://boto3.readthedocs.io/en/latest/reference/services/s3.html#S3.Client.download_fileobj

>>> import boto3
>>> boto3.__version__
'1.7.62'
>>> s3 = boto3.resource("s3")
>>> s3.download_fileobj
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 's3.ServiceResource' object has no attribute 'download_fileobj'

[mandarvaze]

@ns-cweber change how you "create" s3 as follows :

s3 = boto3.client('s3')

You have created s3 as a 'resource' - hence the error.

[ns-cweber]

Ah, that's it. Thanks very much. 👍