Module: Technoweenie::AttachmentFu::Backends::S3Backend
- Defined in:
- lib/technoweenie/attachment_fu/backends/s3_backend.rb
Overview
AWS::S3 Storage Backend
Enables use of Amazon’s Simple Storage Service as a storage mechanism
Requirements
Requires the aws-sdk-v1 gem.
Configuration
Configuration is done via #{Rails.root}/config/amazon_s3.yml
and is loaded according to the #{Rails.env}
. The minimum connection options that you must specify are a bucket name, your access key id and your secret access key. If you don’t already have your access keys, all you need to sign up for the S3 service is an account at Amazon. You can sign up for S3 and get access keys by visiting aws.amazon.com/s3.
If you wish to use Amazon CloudFront to serve the files, you can also specify a distibution domain for the bucket. To read more about CloudFront, visit aws.amazon.com/cloudfront
Example configuration (#Rails.root/config/amazon_s3.yml)
development:
bucket_name: appname_development
access_key_id: <your key>
secret_access_key: <your key>
distribution_domain: XXXX.cloudfront.net
test:
bucket_name: appname_test
access_key_id: <your key>
secret_access_key: <your key>
distribution_domain: XXXX.cloudfront.net
production:
bucket_name: appname
access_key_id: <your key>
secret_access_key: <your key>
distribution_domain: XXXX.cloudfront.net
You can change the location of the config path by passing a full path to the :s3_config_path option.
has_attachment :storage => :s3, :s3_config_path => (#{Rails.root} + '/config/s3.yml')
Required configuration parameters
-
:access_key_id
- The access key id for your S3 account. Provided by Amazon. -
:secret_access_key
- The secret access key for your S3 account. Provided by Amazon. -
:bucket_name
- A unique bucket name (think of the bucket_name as being like a database name).
If any of these required arguments is missing, a MissingAccessKey exception will be raised from AWS::S3.
About bucket names
Bucket names have to be globaly unique across the S3 system. And you can only have up to 100 of them, so it’s a good idea to think of a bucket as being like a database, hence the correspondance in this implementation to the development, test, and production environments.
The number of objects you can store in a bucket is, for all intents and purposes, unlimited.
Optional configuration parameters
-
:server
- The server to make requests to. Defaults tos3.amazonaws.com
. -
:port
- The port to the requests should be made on. Defaults to 80 or 443 if:use_ssl
is set. -
:use_ssl
- If set to true,:port
will be implicitly set to 443, unless specified otherwise. Defaults to false. -
:distribution_domain
- The CloudFront distribution domain for the bucket. This can either be the assigneddistribution domain (ie. XXX.cloudfront.net) or a chosen domain using a CNAME. See CloudFront for more details.
Usage
To specify S3 as the storage mechanism for a model, set the acts_as_attachment :storage
option to :s3
.
class Photo < ActiveRecord::Base
:storage => :s3
end
Customizing the path
By default, files are prefixed using a pseudo hierarchy in the form of :table_name/:id
, which results in S3 urls that look like: http(s)://:server/:bucket_name/:table_name/:id/:filename with :table_name representing the customizable portion of the path. You can customize this prefix using the :path_prefix
option:
class Photo < ActiveRecord::Base
:storage => :s3, :path_prefix => 'my/custom/path'
end
Which would result in URLs like http(s)://:server/:bucket_name/my/custom/path/:id/:filename.
Using different bucket names on different models
By default the bucket name that the file will be stored to is the one specified by the :bucket_name
key in the amazon_s3.yml file. You can use the :bucket_key
option to overide this behavior on a per model basis. For instance if you want a bucket that will hold only Photos you can do this:
class Photo < ActiveRecord::Base
:storage => :s3, :bucket_key => :photo_bucket_name
end
And then your amazon_s3.yml file needs to look like this.
development:
bucket_name: appname_development
access_key_id: <your key>
secret_access_key: <your key>
test:
bucket_name: appname_test
access_key_id: <your key>
secret_access_key: <your key>
production:
bucket_name: appname
photo_bucket_name: appname_photos
access_key_id: <your key>
secret_access_key: <your key>
If the bucket_key you specify is not there in a certain environment then attachment_fu will
default to the <tt>bucket_name</tt> key. This way you only have to create special buckets
this can be helpful if you only need special buckets in certain environments.
Permissions
By default, files are stored on S3 with public access permissions. You can customize this using the :s3_access
option to has_attachment
. Available values are :private
, :public_read_write
, and :authenticated_read
.
Other options
Of course, all the usual configuration options apply, such as content_type and thumbnails:
class Photo < ActiveRecord::Base
:storage => :s3, :content_type => ['application/pdf', :image], :resize_to => 'x50'
:storage => :s3, :thumbnails => { :thumb => [50, 50], :geometry => 'x50' }
end
Accessing S3 URLs
You can get an object’s URL using the s3_url accessor. For example, assuming that for your postcard app you had a bucket name like ‘postcard_world_development’, and an attachment model called Photo:
@postcard.s3_url # => http(s)://s3.amazonaws.com/postcard_world_development/photos/1/mexico.jpg
The resulting url is in the form: http(s)://:server/:bucket_name/:table_name/:id/:file. The optional thumbnail argument will output the thumbnail’s filename (if any).
Additionally, you can get an object’s base path relative to the bucket root using base_path
:
@photo.file_base_path # => photos/1
And the full path (including the filename) using full_filename
:
@photo.full_filename # => photos/
Niether base_path
or full_filename
include the bucket name as part of the path. You can retrieve the bucket name using the bucket_name
method.
Accessing CloudFront URLs
You can get an object’s CloudFront URL using the cloudfront_url accessor. Using the example from above: The resulting url is in the form: :distribution_domain/:table_name/:id/:file
If you set :cloudfront to true in your model, the public_filename will be the CloudFront URL, not the S3 URL.
Defined Under Namespace
Modules: ClassMethods Classes: ConfigFileNotFoundError, RequiredLibraryNotFoundError
Class Method Summary collapse
- .distribution_domain ⇒ Object
- .hostname ⇒ Object
-
.included(base) ⇒ Object
:nodoc:.
- .port_string ⇒ Object
- .protocol ⇒ Object
Instance Method Summary collapse
-
#attachment_path_id ⇒ Object
The attachment ID used in the full path of a file.
-
#authenticated_s3_url(*args) ⇒ Object
All private objects are accessible via an authenticated GET request to the S3 servers.
-
#base_path(thumbnail = nil) ⇒ Object
The pseudo hierarchy containing the file relative to the bucket name Example:
:table_name/:id
. - #cloudfront_distribution_domain ⇒ Object
-
#cloudfront_url(thumbnail = nil) ⇒ Object
All public objects are accessible via a GET request to CloudFront.
- #create_temp_file ⇒ Object
- #current_data ⇒ Object
-
#filename=(value) ⇒ Object
Overwrites the base filename writer in order to store the old filename.
-
#full_filename(thumbnail = nil) ⇒ Object
The full path to the file relative to the bucket name Example:
:table_name/:id/:filename
. - #public_filename(*args) ⇒ Object
- #s3_hostname ⇒ Object
- #s3_port_string ⇒ Object
- #s3_protocol ⇒ Object
-
#s3_url(thumbnail = nil) ⇒ Object
All public objects are accessible via a GET request to the S3 servers.
Class Method Details
.distribution_domain ⇒ Object
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 219 def self.distribution_domain @distribution_domain = s3_config[:distribution_domain] end |
.hostname ⇒ Object
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 211 def self.hostname @hostname ||= s3_config[:server] || 's3.amazonaws.com' end |
.included(base) ⇒ Object
:nodoc:
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 174 def self.included(base) #:nodoc: mattr_reader :bucket_name, :s3_config, :s3_conn, :bucket begin require 'aws-sdk-v1' rescue LoadError raise RequiredLibraryNotFoundError.new('aws-sdk-v1 could not be loaded. Make sure the gem is installed.') end begin @@s3_config_path = base.[:s3_config_path] || File.join(Rails.root, 'config', 'amazon_s3.yml') @@s3_config = @@s3_config = YAML.load(ERB.new(File.read(@@s3_config_path)).result)[Rails.env].symbolize_keys #rescue # raise ConfigFileNotFoundError.new('File %s not found' % @@s3_config_path) end bucket_key = base.[:bucket_key] if bucket_key and s3_config[bucket_key.to_sym] eval_string = "def bucket_name()\n \"#{s3_config[bucket_key.to_sym]}\"\nend" else eval_string = "def bucket_name()\n \"#{s3_config[:bucket_name]}\"\nend" end base.class_eval(eval_string, __FILE__, __LINE__) @@s3_conn = AWS::S3.new(s3_config.slice(:access_key_id, :secret_access_key)) @@bucket = s3_conn.buckets[s3_config[:bucket_name]] #Base.establish_connection!(s3_config.slice(:access_key_id, :secret_access_key, :server, :port, :use_ssl, :persistent, :proxy)) base.before_update :rename_file end |
.port_string ⇒ Object
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 215 def self.port_string @port_string ||= (s3_config[:port].nil? || s3_config[:port] == (s3_config[:use_ssl] ? 443 : 80)) ? '' : ":#{s3_config[:port]}" end |
.protocol ⇒ Object
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 207 def self.protocol @protocol ||= s3_config[:use_ssl] ? 'https://' : 'http://' end |
Instance Method Details
#attachment_path_id ⇒ Object
The attachment ID used in the full path of a file
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 248 def ((respond_to?(:parent_id) && parent_id) || id).to_s end |
#authenticated_s3_url(*args) ⇒ Object
All private objects are accessible via an authenticated GET request to the S3 servers. You can generate an authenticated url for an object like this:
@photo.authenticated_s3_url
By default authenticated urls expire 5 minutes after they were generated.
Expiration options can be specified either with an absolute time using the :expires
option, or with a number of seconds relative to now with the :expires_in
option:
# Absolute expiration date (October 13th, 2025)
@photo.authenticated_s3_url(:expires => Time.mktime(2025,10,13).to_i)
# Expiration in five hours from now
@photo.authenticated_s3_url(:expires_in => 5.hours)
You can specify whether the url should go over SSL with the :use_ssl
option. By default, the ssl settings for the current connection will be used:
@photo.authenticated_s3_url(:use_ssl => true)
Finally, the optional thumbnail argument will output the thumbnail’s filename (if any):
@photo.authenticated_s3_url('thumbnail', :expires_in => 5.hours, :use_ssl => true)
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 324 def authenticated_s3_url(*args) = args. [:expires] = [:expires_in].to_i if [:expires_in] [:secure] = [:use_ssl] if [:use_ssl] .delete(:expires_in) if [:expires_in] .delete(:use_ssl) if [:use_ssl] thumbnail = args.shift bucket.objects[full_filename(thumbnail)].url_for(:read, ).to_s end |
#base_path(thumbnail = nil) ⇒ Object
The pseudo hierarchy containing the file relative to the bucket name Example: :table_name/:id
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 254 def base_path(thumbnail = nil) file_system_path = (thumbnail ? thumbnail_class : self).[:path_prefix] File.join(file_system_path, ) end |
#cloudfront_distribution_domain ⇒ Object
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 358 def cloudfront_distribution_domain Technoweenie::AttachmentFu::Backends::S3Backend.distribution_domain end |
#cloudfront_url(thumbnail = nil) ⇒ Object
All public objects are accessible via a GET request to CloudFront. You can generate a url for an object using the cloudfront_url method.
@photo.cloudfront_url
The resulting url is in the form: http://:distribution_domain/:table_name/:id/:file
using the :distribution_domain
variable set in the configuration parameters in #{Rails.root}/config/amazon_s3.yml
.
The optional thumbnail argument will output the thumbnail’s filename (if any).
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 288 def cloudfront_url(thumbnail = nil) s3_protocol + cloudfront_distribution_domain + "/" + full_filename(thumbnail) end |
#create_temp_file ⇒ Object
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 334 def create_temp_file write_to_temp_file current_data end |
#current_data ⇒ Object
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 338 def current_data if [:encrypted_storage] && self.respond_to?(:encryption_key) && self.encryption_key != nil EncryptedData.decrypt_data(bucket.objects[full_filename].read, self.encryption_key) else bucket.objects[full_filename].read end end |
#filename=(value) ⇒ Object
Overwrites the base filename writer in order to store the old filename
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 242 def filename=(value) @old_filename = filename unless filename.nil? || @old_filename write_attribute :filename, sanitize_filename(value) end |
#full_filename(thumbnail = nil) ⇒ Object
The full path to the file relative to the bucket name Example: :table_name/:id/:filename
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 261 def full_filename(thumbnail = nil) File.join(base_path(thumbnail), thumbnail_name_for(thumbnail)) end |
#public_filename(*args) ⇒ Object
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 292 def public_filename(*args) if [:cloudfront] cloudfront_url(*args) else s3_url(*args) end end |
#s3_hostname ⇒ Object
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 350 def s3_hostname Technoweenie::AttachmentFu::Backends::S3Backend.hostname end |
#s3_port_string ⇒ Object
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 354 def s3_port_string Technoweenie::AttachmentFu::Backends::S3Backend.port_string end |
#s3_protocol ⇒ Object
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 346 def s3_protocol Technoweenie::AttachmentFu::Backends::S3Backend.protocol end |
#s3_url(thumbnail = nil) ⇒ Object
All public objects are accessible via a GET request to the S3 servers. You can generate a url for an object using the s3_url method.
@photo.s3_url
The resulting url is in the form: http(s)://:server/:bucket_name/:table_name/:id/:file
where the :server
variable defaults to AWS::S3 URL::DEFAULT_HOST
(s3.amazonaws.com) and can be set using the configuration parameters in #{Rails.root}/config/amazon_s3.yml
.
The optional thumbnail argument will output the thumbnail’s filename (if any).
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# File 'lib/technoweenie/attachment_fu/backends/s3_backend.rb', line 275 def s3_url(thumbnail = nil) File.join(s3_protocol + s3_hostname + s3_port_string, bucket_name, full_filename(thumbnail)) end |