How do I create an query-string authorized s3 URL?

Question

Apparently s3 supports urls in the form:

http://s3.amazonaws.com/bucket/file.txt?some_kind_of_auth_token

How do I generate a "secure" URL like this?

Answer 1

This is the official help which covers how to do this.

Look for the section called "Query String Request Authentication Alternative"

GET /photos/puppy.jpg?AWSAccessKeyId=AKIAIOSFODNN7EXAMPLE&
    Signature=rucSbH0yNEcP9oM2XNlouVI3BH4%3D&
    Expires=1175139620 HTTP/1.1

Here's a snip from the help page.

You can authenticate certain types of requests by passing the required information as query-string parameters instead of using the Authorization HTTP header. This is useful for enabling direct third-party browser access to your private Amazon S3 data, without proxying the request. The idea is to construct a "pre-signed" request and encode it as a URL that an end-user's browser can retrieve. Additionally, you can limit a pre-signed request by specifying an expiration time.