Amazon AWS S3 data store for use with the Dragonfly gem.

NOTE: version 1.2 saves files into a different directory structure, e.g. '2015/08/03/5bccfdd8-0de2-4efc-b3f3-f4e96bcc4afa/file.png' rather than '2015/08/03/12/03/24/492/file.png'.

However this does not affect any functionality and won't break any of your old content! It's just more robust.


gem 'dragonfly-s3_data_store'


Configuration (remember the require)

require 'dragonfly/s3_data_store'

Dragonfly.app.configure do
  # ...

  datastore :s3,
    bucket_name: 'my-bucket',
    access_key_id: 'blahblahblah',
    secret_access_key: 'blublublublu'

  # ...

Available configuration options

:region               # default 'us-east-1', see Dragonfly::S3DataStore::REGIONS for options
:storage_headers      # defaults to {'x-amz-acl' => 'public-read'}, can be overridden per-write - see below
:url_scheme           # defaults to "http"
:url_host             # defaults to "<bucket-name>.s3.amazonaws.com", or "s3.amazonaws.com/<bucket-name>" if not a valid subdomain
:use_iam_profile      # boolean - if true, no need for access_key_id or secret_access_key
:root_path            # store all content under a subdirectory - uids will be relative to this - defaults to nil
:fog_storage_options  # hash for passing any extra options to Fog::Storage.new, e.g. {path_style: true}

Per-storage options

Dragonfly.app.store(some_file, {'some' => 'metadata'}, path: 'some/path.txt', headers: {'x-amz-acl' => 'public-read-write'})


class MyModel
  dragonfly_accessor :photo do
    storage_options do |attachment|
        path: "some/path/#{some_instance_method}/#{rand(100)}",
        headers: {"x-amz-acl" => "public-read-write"}

BEWARE!!!! you must make sure the path (which will become the uid for the content) is unique and changes each time the content is changed, otherwise you could have caching problems, as the generated urls will be the same for the same uid.

Serving directly from S3

You can get the S3 url using




or with an expiring url:

my_model.attachment.remote_url(expires: 3.days.from_now)

or with an https url:

my_model.attachment.remote_url(scheme: 'https')   # also configurable for all urls with 'url_scheme'

or with a custom host:

my_model.attachment.remote_url(host: 'custom.domain')   # also configurable for all urls with 'url_host'

or with other query parameters (needs an expiry):

my_model.attachment.remote_url(expires: 3.days.from_now, query: {'response-content-disposition' => 'attachment'})  # URL that downloads the file