Python S3 Examples

Creating a Connection

This creates a connection so that you can interact with the server.

import boto
import boto.s3.connection
access_key = 'put your access key here!'
secret_key = 'put your secret key here!'

conn = boto.connect_s3(
        aws_access_key_id = access_key,
        aws_secret_access_key = secret_key,
        host = '',
        #is_secure=False,               # uncomment if you are not using ssl
        calling_format = boto.s3.connection.OrdinaryCallingFormat(),

Listing Owned Buckets

This gets a list of Buckets that you own. This also prints out the bucket name and creation date of each bucket.

for bucket in conn.get_all_buckets():
                name =,
                created = bucket.creation_date,

The output will look something like this:

mahbuckat1   2011-04-21T18:05:39.000Z
mahbuckat2   2011-04-21T18:05:48.000Z
mahbuckat3   2011-04-21T18:07:18.000Z

Creating a Bucket

This creates a new bucket called my-new-bucket

bucket = conn.create_bucket('my-new-bucket')

Listing a Bucket’s Content

This gets a list of objects in the bucket. This also prints out each object’s name, the file size, and last modified date.

for key in bucket.list():
                name =,
                size = key.size,
                modified = key.last_modified,

The output will look something like this:

myphoto1.jpg 251262  2011-08-08T21:35:48.000Z
myphoto2.jpg 262518  2011-08-08T21:38:01.000Z

Deleting a Bucket


The Bucket must be empty! Otherwise it won’t work!


Forced Delete for Non-empty Buckets


not available in python

Creating an Object

This creates a file hello.txt with the string "Hello World!"

key = bucket.new_key('hello.txt')
key.set_contents_from_string('Hello World!')

Uploading an Object or a File

This creates a file logo.png with the contents from the file "logo.png"

key = bucket.new_key('logo.png')

Change an Object’s ACL

This makes the object hello.txt to be publicly readable, and secret_plans.txt to be private.

hello_key = bucket.get_key('hello.txt')
plans_key = bucket.get_key('secret_plans.txt')

Download an Object (to a file)

This downloads the object perl_poetry.pdf and saves it in /home/larry/documents/

key = bucket.get_key('perl_poetry.pdf')

Delete an Object

This deletes the object goodbye.txt


Generate Object Download URLs (signed and unsigned)

This generates an unsigned download URL for hello.txt. This works because we made hello.txt public by setting the ACL above. This then generates a signed download URL for secret_plans.txt that will work for 1 hour. Signed download URLs will work for the time period even if the object is private (when the time period is up, the URL will stop working).

hello_key = bucket.get_key('hello.txt')
hello_url = hello_key.generate_url(0, query_auth=False, force_http=True)

plans_key = bucket.get_key('secret_plans.txt')
plans_url = plans_key.generate_url(3600, query_auth=True, force_http=True)

The output of this will look something like:

Using S3 API Extensions

To use the boto3 client to tests the RadosGW extensions to the S3 API, the extensions file should be placed under: ~/.aws/models/s3/2006-03-01/ directory. For example, unordered list of objects could be fetched using:

print(conn.list_objects(Bucket='my-new-bucket', AllowUnordered=True))

Without the extensions file, in the above example, boto3 would complain that the AllowUnordered argument is invalid.