aboutsummaryrefslogtreecommitdiffstats
path: root/actionpack/lib/action_controller/metal/data_streaming.rb
blob: 0670a58d979505b62868876bfde9652e372e251a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
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
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
require 'active_support/core_ext/file/path'
require 'action_controller/metal/exceptions'

module ActionController #:nodoc:
  # Methods for sending arbitrary data and for streaming files to the browser,
  # instead of rendering.
  module DataStreaming
    extend ActiveSupport::Concern

    include ActionController::Rendering

    DEFAULT_SEND_FILE_OPTIONS = {
      :type         => 'application/octet-stream'.freeze,
      :disposition  => 'attachment'.freeze,
    }.freeze

    protected
      # Sends the file. This uses a server-appropriate method (such as X-Sendfile)
      # via the Rack::Sendfile middleware. The header to use is set via
      # config.action_dispatch.x_sendfile_header.
      # Your server can also configure this for you by setting the X-Sendfile-Type header.
      #
      # Be careful to sanitize the path parameter if it is coming from a web
      # page. <tt>send_file(params[:path])</tt> allows a malicious user to
      # download any file on your server.
      #
      # Options:
      # * <tt>:filename</tt> - suggests a filename for the browser to use.
      #   Defaults to <tt>File.basename(path)</tt>.
      # * <tt>:type</tt> - specifies an HTTP content type.
      #   You can specify either a string or a symbol for a registered type register with
      #   <tt>Mime::Type.register</tt>, for example :json
      #   If omitted, type will be guessed from the file extension specified in <tt>:filename</tt>.
      #   If no content type is registered for the extension, default type 'application/octet-stream' will be used.
      # * <tt>:disposition</tt> - specifies whether the file will be shown inline or downloaded.
      #   Valid values are 'inline' and 'attachment' (default).
      # * <tt>:status</tt> - specifies the status code to send with the response. Defaults to 200.
      # * <tt>:url_based_filename</tt> - set to +true+ if you want the browser guess the filename from
      #   the URL, which is necessary for i18n filenames on certain browsers
      #   (setting <tt>:filename</tt> overrides this option).
      #
      # The default Content-Type and Content-Disposition headers are
      # set to download arbitrary binary files in as many browsers as
      # possible. IE versions 4, 5, 5.5, and 6 are all known to have
      # a variety of quirks (especially when downloading over SSL).
      #
      # Simple download:
      #
      #   send_file '/path/to.zip'
      #
      # Show a JPEG in the browser:
      #
      #   send_file '/path/to.jpeg', :type => 'image/jpeg', :disposition => 'inline'
      #
      # Show a 404 page in the browser:
      #
      #   send_file '/path/to/404.html', :type => 'text/html; charset=utf-8', :status => 404
      #
      # Read about the other Content-* HTTP headers if you'd like to
      # provide the user with more information (such as Content-Description) in
      # http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.11.
      #
      # Also be aware that the document may be cached by proxies and browsers.
      # The Pragma and Cache-Control headers declare how the file may be cached
      # by intermediaries. They default to require clients to validate with
      # the server before releasing cached responses. See
      # http://www.mnot.net/cache_docs/ for an overview of web caching and
      # http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9
      # for the Cache-Control header spec.
      def send_file(path, options = {}) #:doc:
        raise MissingFile, "Cannot read file #{path}" unless File.file?(path) and File.readable?(path)

        options[:filename] ||= File.basename(path) unless options[:url_based_filename]
        send_file_headers! options

        self.status = options[:status] || 200
        self.content_type = options[:content_type] if options.key?(:content_type)
        self.response_body = File.open(path, "rb")
      end

      # Sends the given binary data to the browser. This method is similar to
      # <tt>render :text => data</tt>, but also allows you to specify whether
      # the browser should display the response as a file attachment (i.e. in a
      # download dialog) or as inline data. You may also set the content type,
      # the apparent file name, and other things.
      #
      # Options:
      # * <tt>:filename</tt> - suggests a filename for the browser to use.
      # * <tt>:type</tt> - specifies an HTTP content type. Defaults to 'application/octet-stream'. You can specify
      #   either a string or a symbol for a registered type register with <tt>Mime::Type.register</tt>, for example :json
      #   If omitted, type will be guessed from the file extension specified in <tt>:filename</tt>.
      #   If no content type is registered for the extension, default type 'application/octet-stream' will be used.
      # * <tt>:disposition</tt> - specifies whether the file will be shown inline or downloaded.
      #   Valid values are 'inline' and 'attachment' (default).
      # * <tt>:status</tt> - specifies the status code to send with the response. Defaults to 200.
      #
      # Generic data download:
      #
      #   send_data buffer
      #
      # Download a dynamically-generated tarball:
      #
      #   send_data generate_tgz('dir'), :filename => 'dir.tgz'
      #
      # Display an image Active Record in the browser:
      #
      #   send_data image.data, :type => image.content_type, :disposition => 'inline'
      #
      # See +send_file+ for more information on HTTP Content-* headers and caching.
      def send_data(data, options = {}) #:doc:
        send_file_headers! options.dup
        render options.slice(:status, :content_type).merge(:text => data)
      end

    private
      def send_file_headers!(options)
        type_provided = options.has_key?(:type)
        
        options.update(DEFAULT_SEND_FILE_OPTIONS.merge(options))
        [:type, :disposition].each do |arg|
          raise ArgumentError, ":#{arg} option required" if options[arg].nil?
        end

        disposition = options[:disposition]
        disposition += %(; filename="#{options[:filename]}") if options[:filename]

        content_type = options[:type]

        if content_type.is_a?(Symbol)
          extension = Mime[content_type]
          raise ArgumentError, "Unknown MIME type #{options[:type]}" unless extension
          self.content_type = extension
        else
          if !type_provided && options[:filename]
            # If type wasn't provided, try guessing from file extension.
            content_type = Mime::Type.lookup_by_extension(File.extname(options[:filename]).downcase.tr('.','')) || content_type
          end
          self.content_type = content_type
        end

        headers.merge!(
          'Content-Disposition'       => disposition,
          'Content-Transfer-Encoding' => 'binary'
        )

        response.sending_file = true

        # Fix a problem with IE 6.0 on opening downloaded files:
        # If Cache-Control: no-cache is set (which Rails does by default),
        # IE removes the file it just downloaded from its cache immediately
        # after it displays the "open/save" dialog, which means that if you
        # hit "open" the file isn't there anymore when the application that
        # is called for handling the download is run, so let's workaround that
        response.cache_control[:public] ||= false
      end
  end
end