Class: Rack::Multipart::Parser

Inherits:
Object
  • Object
show all
Defined in:
lib/rack/multipart/parser.rb

Overview

Rack::Multipart::Parser handles parsing of multipart/form-data requests.

File Parameter Contents

When processing file uploads, the parser returns a hash containing information about uploaded files. For file parameters, the hash includes:

  • :filename - The original filename, already URL decoded by the parser

  • :type - The content type of the uploaded file

  • :name - The parameter name from the form

  • :tempfile - A Tempfile object containing the uploaded data

  • :head - The raw header content for this part

Defined Under Namespace

Classes: BoundedIO, Collector, MultipartInfo

Constant Summary collapse

BUFSIZE = 
1_048_576
TEXT_PLAIN = 
"text/plain"
TEMPFILE_FACTORY = 
lambda { |filename, content_type|
  extension = ::File.extname(filename.gsub("\0", '%00'))[0, 129]

  Tempfile.new(["RackMultipart", extension])
}
EMPTY = 
MultipartInfo.new(nil, [])

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(boundary, tempfile, bufsize, query_parser) ⇒ Parser

Returns a new instance of Parser.



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# File 'lib/rack/multipart/parser.rb', line 214

def initialize(boundary, tempfile, bufsize, query_parser)
  @query_parser   = query_parser
  @params         = query_parser.make_params
  @bufsize        = bufsize

  @state = :FAST_FORWARD
  @mime_index = 0
  @collector = Collector.new tempfile

  @sbuf = StringScanner.new("".dup)
  @body_regex = /(?:#{EOL}|\A)--#{Regexp.quote(boundary)}(?:#{EOL}|--)/m
  @body_regex_at_end = /#{@body_regex}\z/m
  @end_boundary_size = boundary.bytesize + 4 # (-- at start, -- at finish)
  @rx_max_size = boundary.bytesize + 6 # (\r\n-- at start, either \r\n or -- at finish)
  @head_regex = /(.*?#{EOL})#{EOL}/m
end

Instance Attribute Details

#state ⇒ Object (readonly)

Returns the value of attribute state.



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# File 'lib/rack/multipart/parser.rb', line 212

def state
  @state
end

Class Method Details

.parse(io, content_length, content_type, tmpfile, bufsize, qp) ⇒ Object 



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# File 'lib/rack/multipart/parser.rb', line 101

def self.parse(io, content_length, content_type, tmpfile, bufsize, qp)
  return EMPTY if 0 == content_length

  boundary = parse_boundary content_type
  return EMPTY unless boundary

  if boundary.length > 70
    # RFC 1521 Section 7.2.1 imposes a 70 character maximum for the boundary.
    # Most clients use no more than 55 characters.
    raise BoundaryTooLongError, "multipart boundary size too large (#{boundary.length} characters)"
  end

  io = BoundedIO.new(io, content_length) if content_length

  parser = new(boundary, tmpfile, bufsize, qp)
  parser.parse(io)

  parser.result
end

.parse_boundary(content_type) ⇒ Object 



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# File 'lib/rack/multipart/parser.rb', line 94

def self.parse_boundary(content_type)
  return unless content_type
  data = content_type.match(MULTIPART)
  return unless data
  data[1]
end

Instance Method Details

#parse(io) ⇒ Object 



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# File 'lib/rack/multipart/parser.rb', line 231

def parse(io)
  outbuf = String.new
  read_data(io, outbuf)

  loop do
    status =
      case @state
      when :FAST_FORWARD
        handle_fast_forward
      when :CONSUME_TOKEN
        handle_consume_token
      when :MIME_HEAD
        handle_mime_head
      when :MIME_BODY
        handle_mime_body
      else # when :DONE
        return
      end

    read_data(io, outbuf) if status == :want_read
  end
end

#result ⇒ Object 



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# File 'lib/rack/multipart/parser.rb', line 254

def result
  @collector.each do |part|
    part.get_data do |data|
      tag_multipart_encoding(part.filename, part.content_type, part.name, data)
      name, data = handle_dummy_encoding(part.name, data)
      @query_parser.normalize_params(@params, name, data)
    end
  end
  MultipartInfo.new @params.to_params_hash, @collector.find_all(&:file?).map(&:body)
end