Class: Rack::File

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

Overview

Rack::File serves files below the root directory given, according to the path info of the Rack request. e.g. when Rack::File.new(“/etc”) is used, you can access ‘passwd’ file as localhost:9292/passwd

Handlers can detect if bodies are a Rack::File, and use mechanisms like sendfile on the path.

Defined Under Namespace

Classes: Iterator

Constant Summary collapse

ALLOWED_VERBS = 
%w[GET HEAD OPTIONS]
ALLOW_HEADER = 
ALLOWED_VERBS.join(', ')

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(root, headers = {}, default_mime = 'text/plain') ⇒ File

Returns a new instance of File.



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# File 'lib/rack/file.rb', line 22

def initialize(root, headers={}, default_mime = 'text/plain')
  @root = root
  @headers = headers
  @default_mime = default_mime
  @head = Rack::Head.new(lambda { |env| get env })
end

Instance Attribute Details

#root ⇒ Object (readonly)

Returns the value of attribute root.



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# File 'lib/rack/file.rb', line 20

def root
  @root
end

Instance Method Details

#call(env) ⇒ Object 



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# File 'lib/rack/file.rb', line 29

def call(env)
  # HEAD requests drop the response body, including 4xx error messages.
  @head.call env
end

#get(env) ⇒ Object 



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# File 'lib/rack/file.rb', line 34

def get(env)
  request = Rack::Request.new env
  unless ALLOWED_VERBS.include? request.request_method
    return fail(405, "Method Not Allowed", {'Allow' => ALLOW_HEADER})
  end

  path_info = Utils.unescape_path request.path_info
  return fail(400, "Bad Request") unless Utils.valid_path?(path_info)

  clean_path_info = Utils.clean_path_info(path_info)
  path = ::File.join(@root, clean_path_info)

  available = begin
    ::File.file?(path) && ::File.readable?(path)
  rescue SystemCallError
    false
  end

  if available
    serving(request, path)
  else
    fail(404, "File not found: #{path_info}")
  end
end

#serving(request, path) ⇒ Object 



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# File 'lib/rack/file.rb', line 59

def serving(request, path)
  if request.options?
    return [200, {'Allow' => ALLOW_HEADER, CONTENT_LENGTH => '0'}, []]
  end
  last_modified = ::File.mtime(path).httpdate
  return [304, {}, []] if request.get_header('HTTP_IF_MODIFIED_SINCE') == last_modified

  headers = { "Last-Modified" => last_modified }
  mime_type = mime_type path, @default_mime
  headers[CONTENT_TYPE] = mime_type if mime_type

  # Set custom headers
  @headers.each { |field, content| headers[field] = content } if @headers

  response = [ 200, headers ]

  size = filesize path

  range = nil
  ranges = Rack::Utils.get_byte_ranges(request.get_header('HTTP_RANGE'), size)
  if ranges.nil? || ranges.length > 1
    # No ranges, or multiple ranges (which we don't support):
    # TODO: Support multiple byte-ranges
    response[0] = 200
    range = 0..size-1
  elsif ranges.empty?
    # Unsatisfiable. Return error, and file size:
    response = fail(416, "Byte range unsatisfiable")
    response[1]["Content-Range"] = "bytes */#{size}"
    return response
  else
    # Partial content:
    range = ranges[0]
    response[0] = 206
    response[1]["Content-Range"] = "bytes #{range.begin}-#{range.end}/#{size}"
    size = range.end - range.begin + 1
  end

  response[2] = [response_body] unless response_body.nil?

  response[1][CONTENT_LENGTH] = size.to_s
  response[2] = make_body request, path, range
  response
end