Amazon S3

  1. Amazon S3
    1. Warning
    2. Description
    3. Author
    4. Requirements
    5. List of user configurable parameters
      1. access-key
      2. secret-key
      3. https
    6. List of Procedures
      1. list-buckets
      2. bucket-exists?
      3. create-bucket!
      4. delete-bucket!
      5. list-objects
      6. put-object!
      7. put-string!
      8. put-sexp!
      9. put-file!
      10. get-file
      11. get-object
      12. get-string
      13. get-sexp
      14. delete-object!
    7. List of macros
      1. with-bucket
    8. Version History
      1. 0.8
      2. 4

Warning

This API will change. More S3 features are being added and the API is being changed to be more flexible and easier to use.

Description

A simple API to use the Amazon S3 service. The current version does not come close to supporting all of S3 or AWS. If there is something in the API that you need, that isn't currently there, let me know at t@thintz.com.

Author

Thomas Hintz

Contact me at t@thintz.com.

Requirements

List of user configurable parameters

access-key

[parameter] (access-key [string])

This needs to be set before you can access S3. This is your AWS access key.

secret-key

[parameter] (secret-key [string])

This needs to be set before you can access S3. This is your AWS secret key.

https

[parameter] (https [boolean])

If set to #t Amazon S3 will be accessed via https. Defaults to #f.

List of Procedures

All procedures return three values. The first will be the return value for the procedure. The second is the request-uri. The third is the response object. See http-client's call-with-input-request (Amazon S3 uses this and returns the same values).

Errors are unspecified and will occur if you do anything that results in an error. Such as: not setting up your AWS access or secret keys correctly, trying to access something you don't have permissions to, trying to create a bucket that already exists, etc. This is subject to change.

list-buckets

[procedure] (list-buckets)

Returns a list of your buckets.

bucket-exists?

[procedure] (bucket-exists? bucket)

Returns #t when the specified bucket exists, #f otherwise.

create-bucket!

[procedure] (create-bucket! bucket)

Creates a bucket. If the bucket already exists, you will most likely get an error. The result of this call is unspecified.

delete-bucket!

[procedure] (delete-bucket! bucket)

Attempts to delete the specified bucket. If the bucket doesn't exist or can't be deleted, you will get an unspecified error.

list-objects

[procedure] (list-objects bucket)

Returns a list of all the objects in the specified bucket.

put-object!

[procedure] (put-object! bucket key object-thunk object-length object-type)

This is the basic/raw way of putting an object on S3. It is recommended to use either put-string! or put-sexp!, if you can. Takes a bucket, a key (string) for identifying the object, a thunk that returns the object, the length of the object, and the object type.

If the key already specifies an object on S3, the object will be replaced.

As an example, put-string! is implemented like this: (put-object! bucket key (lambda () string) (string-length string) "text/plain").

The return is unspecified.

put-string!

[procedure] (put-string! bucket key string)

Simply takes a bucket, key (string) to identify the string, and the string to put on S3; and pushes the string to S3.

If the key already specifies an string on S3, the string will be replaced.

The return is unspecified.

put-sexp!

[procedure] (put-sexp! bucket key sexp)

Simply takes a bucket, key (string) to identify the sexp, and a quoted s-expression to put on S3; and pushes the s-expression to S3.

If the key already specifies a s-exp on S3, the s-exp will be replaced.

The return is unspecified.

put-file!

[procedure] (put-file! bucket key file-path)

Upload a file.

get-file

[procedure] (get-file bucket key file-path)

Retrieve arbitrary item and write it to file-path.

get-object

[procedure] (get-object bucket key)

Takes a bucket and an object key and returns the object identified by the key. Note that all procedures that call to S3 also return request response.

get-string

[procedure] (get-string bucket key)

Takes a bucket and an object key and returns the string identified by the key.

get-sexp

[procedure] (get-sexp bucket key)

Takes a bucket and an object key and returns the s-expression identified by the key. Note that a returned s-expression must be evaled before it can be treated as code.

delete-object!

[procedure] (delete-object! bucket key)

Takes a bucket and an object key and attempts to delete the object identified by the key. If the object can't be deleted, an unspecified error will occur.

List of macros

with-bucket

[syntax] (with-bucket bucket ...)

All amazon-s3 operations in the body will use the specified bucket without requiring it to be explicitly set.

WARNING! DEPRECATED This is broken and only works with calls that start with bucket. The next version of this lib will make this pattern obsolete.

(with-bucket "foo"
  (put-file! "foo-file" "~/foo")
  (get-file "foo-file" "~/foo2"))

(with-bucket "foo"
  (+ 1 2 3)) ; this will not work!

Version History

0.8

4

Initial release.