Cloud Web Apps - Amazon S3 Lab

Amazon S3 is short for Simple Storage Service, which is an object storage service of AWS. This lab introduces the common features of S3.

Official Links

QwikLab: Intro to S3

Operations

1. Create a bucket in Amazon S3

In the AWS Management Console, click S3 on the Services menu to open S3 console.

• Click Create bucket button

  • Name the bucket as mybucket{some random number}, duplicate names are not allowed
  • Leave Region to default value, objects will be only stored to the designated region, explicit transfer to another region is possible

• In the Configure options dialog box

  • Check Keep all versions of an object in the same bucket
  • Leave other options to default value (e.g. no public read access to bucket)

• Finish by clicking Create bucket button

  • If an error concerning the bucket name occurs, go back and change the bucket name until it works

2. Add an object to bucket

An object can be any kind of file: text, image, video and etc.

• Download the Sheep.jpg to your computer

• Select the bucket just created in S3 Management Console

  • Click Upload button
  • Click Add files button
  • Select the image file then click Upload button
  • Once uploaded, the file will be displayed in bucket

3. Manage access permissions on an object

By default, uploaded objects are private, not publicly accessible.

• Click on the S3 link for the image file

  • A XML based Access Denied error will be displayed

• Make the file public

  • Click on the file in console
  • Under Permissions tab, Public access section, select Everyone
  • Select Read object and save
  • Open the S3 link again, the image will be shown

4. Create a Bucket Policy

Grant access to the entire bucket by setting up a policy.

• Find ARN (Amazon Resource Name) of bucket in the Permissions tab,

• Generate Policy

  • Click the Policy generator link
  • Set Select Type of Policy to S3 Bucket Policy, Principal to *
  • Set Actions to GetObject so that anyone will be able to access
  • Append /* to ARN to allow the policy to apply to all objects within the bucket
  • Click Add Statement and then Generate Policy
  • Copy and paste the generated JSON object to Bucket policy editor
  • Save and test by accessing any object

5. Use bucket versioning

• Create a different version of object

  • Upload a different image file with the same as an existing file in bucket
  • Test the S3 link, it will point to the latest version
  • Previous versions could be found by clicking on Latest version
  • By default, the previous version is not accessible via the S3 link, grant access to previous version by appending field s3:GetObjectVersion to policy
  • Save and the policy takes effect

Written by Warren who studies distributed systems at George Washington University. You might wanna follow him on Github