Module: Paperclip::Storage::S3

Defined in:
lib/paperclip/storage/s3.rb

Overview

Amazon’s S3 file hosting service is a scalable, easy place to store files for distribution. You can find out more about it at aws.amazon.com/s3 There are a few S3-specific options for has_attached_file:

  • s3_credentials: Takes a path, a File, or a Hash. The path (or File) must point to a YAML file containing the access_key_id and secret_access_key that Amazon gives you. You can ‘environment-space’ this just like you do to your database.yml file, so different environments can use different accounts:

    development:
  access_key_id: 123...
  secret_access_key: 123...
test:
  access_key_id: abc...
  secret_access_key: abc...
production:
  access_key_id: 456...
  secret_access_key: 456...

    This is not required, however, and the file may simply look like this:

    access_key_id: 456...
secret_access_key: 456...

    In which case, those access keys will be used in all environments. You can also put your bucket name in this file, instead of adding it to the code directly. This is useful when you want the same account but a different bucket for development versus production.

  • s3_permissions: This is a String that should be one of the “canned” access policies that S3 provides (more information can be found here: docs.amazonwebservices.com/AmazonS3/2006-03-01/RESTAccessPolicy.html#RESTCannedAccessPolicies) The default for Paperclip is :public_read.

  • s3_protocol: The protocol for the URLs generated to your S3 assets. Can be either ‘http’ or ‘https’. Defaults to ‘http’ when your :s3_permissions are :public_read (the default), and ‘https’ when your :s3_permissions are anything else.

  • s3_headers: A hash of headers such as => 1.year.from_now.httpdate

  • bucket: This is the name of the S3 bucket that will store your files. Remember that the bucket must be unique across all of Amazon S3. If the bucket does not exist Paperclip will attempt to create it. The bucket name will not be interpolated. You can define the bucket as a Proc if you want to determine it’s name at runtime. Paperclip will call that Proc with attachment as the only argument.

  • s3_host_alias: The fully-qualified domain name (FQDN) that is the alias to the S3 domain of your bucket. Used with the :s3_alias_url url interpolation. See the link in the url entry for more information about S3 domains and buckets.

  • url: There are three options for the S3 url. You can choose to have the bucket’s name placed domain-style (bucket.s3.amazonaws.com) or path-style (s3.amazonaws.com/bucket). Lastly, you can specify a CNAME (which requires the CNAME to be specified as :s3_alias_url. You can read more about CNAMEs and S3 at docs.amazonwebservices.com/AmazonS3/latest/index.html?VirtualHosting.html Normally, this won’t matter in the slightest and you can leave the default (which is path-style, or :s3_path_url). But in some cases paths don’t work and you need to use the domain-style (:s3_domain_url). Anything else here will be treated like path-style. NOTE: If you use a CNAME for use with CloudFront, you can NOT specify https as your :s3_protocol; This is *not supported* by S3/CloudFront. Finally, when using the host alias, the :bucket parameter is ignored, as the hostname is used as the bucket name by S3.

  • path: This is the key under the bucket in which the file will be stored. The URL will be constructed from the bucket and the path. This is what you will want to interpolate. Keys should be unique, like filenames, and despite the fact that S3 (strictly speaking) does not support directories, you can still use a / to separate parts of your file name.

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.extended(base) ⇒ Object 



60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
 
# File 'lib/paperclip/storage/s3.rb', line 60

def self.extended base
  begin
    require 'aws/s3'
  rescue LoadError => e
    e.message << " (You may need to install the aws-s3 gem)"
    raise e
  end

  base.instance_eval do
    @s3_credentials = parse_credentials(@options[:s3_credentials])
    @bucket         = @options[:bucket]         || @s3_credentials[:bucket]
    @bucket         = @bucket.call(self) if @bucket.is_a?(Proc)
    @s3_options     = @options[:s3_options]     || {}
    @s3_permissions = @options[:s3_permissions] || :public_read
    @s3_protocol    = @options[:s3_protocol]    || (@s3_permissions == :public_read ? 'http' : 'https')
    @s3_headers     = @options[:s3_headers]     || {}
    @s3_host_alias  = @options[:s3_host_alias]
    unless @url.to_s.match(/^:s3.*url$/)
      @path          = @path.gsub(/:url/, @url)
      @url           = ":s3_path_url"
    end
    AWS::S3::Base.establish_connection!( @s3_options.merge(
      :access_key_id => @s3_credentials[:access_key_id],
      :secret_access_key => @s3_credentials[:secret_access_key]
    ))
  end
  Paperclip.interpolates(:s3_alias_url) do |attachment, style|
    "#{attachment.s3_protocol}://#{attachment.s3_host_alias}/#{attachment.path(style).gsub(%r{^/}, "")}"
  end
  Paperclip.interpolates(:s3_path_url) do |attachment, style|
    "#{attachment.s3_protocol}://s3.amazonaws.com/#{attachment.bucket_name}/#{attachment.path(style).gsub(%r{^/}, "")}"
  end
  Paperclip.interpolates(:s3_domain_url) do |attachment, style|
    "#{attachment.s3_protocol}://#{attachment.bucket_name}.s3.amazonaws.com/#{attachment.path(style).gsub(%r{^/}, "")}"
  end
end

Instance Method Details

#bucket_name ⇒ Object 



101
102
103
 
# File 'lib/paperclip/storage/s3.rb', line 101

def bucket_name
  @bucket
end

#create_bucket ⇒ Object 



140
141
142
 
# File 'lib/paperclip/storage/s3.rb', line 140

def create_bucket
  AWS::S3::Bucket.create(bucket_name)
end

#exists?(style = default_style) ⇒ Boolean

Returns:

  • (Boolean) 


114
115
116
117
118
119
120
 
# File 'lib/paperclip/storage/s3.rb', line 114

def exists?(style = default_style)
  if original_filename
    AWS::S3::S3Object.exists?(path(style), bucket_name)
  else
    false
  end
end

#expiring_url(time = 3600) ⇒ Object 



97
98
99
 
# File 'lib/paperclip/storage/s3.rb', line 97

def expiring_url(time = 3600)
  AWS::S3::S3Object.url_for(path, bucket_name, :expires_in => time )
end

#flush_deletes ⇒ Object

:nodoc:



164
165
166
167
168
169
170
171
172
173
174
 
# File 'lib/paperclip/storage/s3.rb', line 164

def flush_deletes #:nodoc:
  @queued_for_delete.each do |path|
    begin
      log("deleting #{path}")
      AWS::S3::S3Object.delete(path, bucket_name)
    rescue AWS::S3::ResponseError
      # Ignore this.
    end
  end
  @queued_for_delete = []
end

#flush_writes ⇒ Object

:nodoc:



144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
 
# File 'lib/paperclip/storage/s3.rb', line 144

def flush_writes #:nodoc:
  @queued_for_write.each do |style, file|
    begin
      log("saving #{path(style)}")
      AWS::S3::S3Object.store(path(style),
                              file,
                              bucket_name,
                              {:content_type => instance_read(:content_type),
                               :access => @s3_permissions,
                              }.merge(@s3_headers))
    rescue AWS::S3::NoSuchBucket => e
      create_bucket
      retry
    rescue AWS::S3::ResponseError => e
      raise
    end
  end
  @queued_for_write = {}
end

#parse_credentials(creds) ⇒ Object 



109
110
111
112
 
# File 'lib/paperclip/storage/s3.rb', line 109

def parse_credentials creds
  creds = find_credentials(creds).stringify_keys
  (creds[Rails.env] || creds).symbolize_keys
end

#s3_host_alias ⇒ Object 



105
106
107
 
# File 'lib/paperclip/storage/s3.rb', line 105

def s3_host_alias
  @s3_host_alias
end

#s3_protocol ⇒ Object 



122
123
124
 
# File 'lib/paperclip/storage/s3.rb', line 122

def s3_protocol
  @s3_protocol
end

#to_file(style = default_style) ⇒ Object

Returns representation of the data of the file assigned to the given style, in the format most representative of the current storage.



128
129
130
131
132
133
134
135
136
137
138
 
# File 'lib/paperclip/storage/s3.rb', line 128

def to_file style = default_style
  return @queued_for_write[style] if @queued_for_write[style]
  filename = path(style)
  extname  = File.extname(filename)
  basename = File.basename(filename, extname)
  file = Tempfile.new([basename, extname])
  file.binmode
  file.write(AWS::S3::S3Object.value(path(style), bucket_name))
  file.rewind
  return file
end