The methods provided by the AWS SDK for Python to download files are similar to those provided to upload files.
The download_file method accepts the names of the bucket and object to download and the filename to save the file to.
import boto3
s3 = boto3.client('s3')
s3.download_file('BUCKET_NAME', 'OBJECT_NAME', 'FILE_NAME')
The download_fileobj method accepts a writeable file-like object. The file object must be opened in binary mode, not text mode.
s3 = boto3.client('s3')
with open('FILE_NAME', 'wb') as f:
s3.download_fileobj('BUCKET_NAME', 'OBJECT_NAME', f)
Like their upload cousins, the download methods are provided by the S3 Client, Bucket, and Object classes, and each class provides identical functionality. Use whichever class is convenient.
Also like the upload methods, the download methods support the optional ExtraArgs and Callback parameters.
The list of valid ExtraArgs settings for the download methods is specified in the ALLOWED_DOWNLOAD_ARGS attribute of the S3Transfer object at boto3.s3.transfer.S3Transfer.ALLOWED_DOWNLOAD_ARGS.
The download method's Callback parameter is used for the same purpose as the upload method's. The upload and download methods can both invoke the same Callback class.