<p><strong>This post is linked to from the <a href="/aws.html">AWS: Deep Dive Project</a></strong></p>
<hr>
<p>This post covers how to upload and download files from Amazon's S3 using
Python. Setup is done from the web UI.</p>
<h1 id="create-a-bucket">Create a Bucket</h1>
<p>Go to the <a href="https://s3.console.aws.amazon.com">AWS S3 page</a>.</p>
<p>Click on "+ Create Bucket" and fill out the form. For access, choose
Block all public access. For the rest of the options, the defaults are fine.</p>
<hr>
<h1 id="create-iam-credentials">Create IAM Credentials</h1>
<p>IAM stands for Identity and Access Management.</p>
<h2 id="create-a-policy">Create a Policy</h2>
<p>From the left nav-bar, go to policies. The default policies don't grant
programmatic access, so you need to make a new one.</p>
<p>For admin rights, I just used the visual policy builder and granted it
access to everything. I'll come back and update this guide with how to lock
that down later.</p>
<hr>
<h1 id="add-the-policy-to-a-group">Add the policy to a group</h1>
<p>Go to the groups on the left. Either make a new one or edit an existing one.
Under Permissions, click Attach Policy. If you want, you can also add
<code>AmazonS3FullAccess</code> to see the difference between the two.</p>
<h2 id="createedit-a-user">Create/Edit a User</h2>
<p>On the left nav-bar, go to Users > Add User. Or edit a user that exists.
Fill in the wizard and assign the group.</p>
<hr>
<h1 id="use-python-to-interact-with-s3">Use Python to interact with S3</h1>
<h2 id="install-boto3">Install Boto3</h2>
<p>Python needs boto3 installed to interact with AWS.</p>
<pre><code class="language-bash">pip install boto3
</code></pre>
<h2 id="uploading-and-downloading-files">Uploading and Downloading Files</h2>
<pre><code class="language-python">import boto3

# Fill in the key and key id, or read them from stdin/file/whatever
key_id = ''
key = ''

# Create the authenticated s3 client
session = boto3.Session(aws_access_key_id=key_id, aws_secret_access_key=key)
client = session.client('s3')

# Define the file/object
filename = '/example/file/path'
bucket_name = 'my_bucket'
key = 'my_key'

# Upload Example
client.upload_file(filename, bucket_name, key)

# Download Example
client.download_file(bucket_name, object_name, path)
</code></pre>


Kyle Pericak

Using AWS S3 from Python