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ruby--ruby/lib/open-uri.rb

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Ruby

# frozen_string_literal: true
require 'uri'
require 'stringio'
require 'time'
module Kernel
private
alias open_uri_original_open open # :nodoc:
class << self
alias open_uri_original_open open # :nodoc:
end
def open(name, *rest, **kw, &block) # :nodoc:
if (name.respond_to?(:open) && !name.respond_to?(:to_path)) ||
(name.respond_to?(:to_str) &&
%r{\A[A-Za-z][A-Za-z0-9+\-\.]*://} =~ name &&
(uri = URI.parse(name)).respond_to?(:open))
warn('calling URI.open via Kernel#open is deprecated, call URI.open directly', uplevel: 1)
URI.open(name, *rest, **kw, &block)
else
open_uri_original_open(name, *rest, **kw, &block)
end
end
module_function :open
end
module URI
# Allows the opening of various resources including URIs.
#
# If the first argument responds to the 'open' method, 'open' is called on
# it with the rest of the arguments.
#
# If the first argument is a string that begins with <code>(protocol)://<code>, it is parsed by
# URI.parse. If the parsed object responds to the 'open' method,
# 'open' is called on it with the rest of the arguments.
#
# Otherwise, Kernel#open is called.
#
# OpenURI::OpenRead#open provides URI::HTTP#open, URI::HTTPS#open and
# URI::FTP#open, Kernel#open.
#
# We can accept URIs and strings that begin with http://, https:// and
# ftp://. In these cases, the opened file object is extended by OpenURI::Meta.
def self.open(name, *rest, &block)
if name.respond_to?(:open)
name.open(*rest, &block)
elsif name.respond_to?(:to_str) &&
%r{\A[A-Za-z][A-Za-z0-9+\-\.]*://} =~ name &&
(uri = URI.parse(name)).respond_to?(:open)
uri.open(*rest, &block)
else
open_uri_original_open(name, *rest, &block)
# After Kernel#open override is removed:
#super
end
end
end
# OpenURI is an easy-to-use wrapper for Net::HTTP, Net::HTTPS and Net::FTP.
#
# == Example
#
# It is possible to open an http, https or ftp URL as though it were a file:
#
# URI.open("http://www.ruby-lang.org/") {|f|
# f.each_line {|line| p line}
# }
#
# The opened file has several getter methods for its meta-information, as
# follows, since it is extended by OpenURI::Meta.
#
# URI.open("http://www.ruby-lang.org/en") {|f|
# f.each_line {|line| p line}
# p f.base_uri # <URI::HTTP:0x40e6ef2 URL:http://www.ruby-lang.org/en/>
# p f.content_type # "text/html"
# p f.charset # "iso-8859-1"
# p f.content_encoding # []
# p f.last_modified # Thu Dec 05 02:45:02 UTC 2002
# }
#
# Additional header fields can be specified by an optional hash argument.
#
# URI.open("http://www.ruby-lang.org/en/",
# "User-Agent" => "Ruby/#{RUBY_VERSION}",
# "From" => "foo@bar.invalid",
# "Referer" => "http://www.ruby-lang.org/") {|f|
# # ...
# }
#
# The environment variables such as http_proxy, https_proxy and ftp_proxy
# are in effect by default. Here we disable proxy:
#
# URI.open("http://www.ruby-lang.org/en/", :proxy => nil) {|f|
# # ...
# }
#
# See OpenURI::OpenRead.open and URI.open for more on available options.
#
# URI objects can be opened in a similar way.
#
# uri = URI.parse("http://www.ruby-lang.org/en/")
# uri.open {|f|
# # ...
# }
#
# URI objects can be read directly. The returned string is also extended by
# OpenURI::Meta.
#
# str = uri.read
# p str.base_uri
#
# Author:: Tanaka Akira <akr@m17n.org>
module OpenURI
Options = {
:proxy => true,
:proxy_http_basic_authentication => true,
:progress_proc => true,
:content_length_proc => true,
:http_basic_authentication => true,
:read_timeout => true,
:open_timeout => true,
:ssl_ca_cert => nil,
:ssl_verify_mode => nil,
:ftp_active_mode => false,
:redirect => true,
:encoding => nil,
}
def OpenURI.check_options(options) # :nodoc:
options.each {|k, v|
next unless Symbol === k
unless Options.include? k
raise ArgumentError, "unrecognized option: #{k}"
end
}
end
def OpenURI.scan_open_optional_arguments(*rest) # :nodoc:
if !rest.empty? && (String === rest.first || Integer === rest.first)
mode = rest.shift
if !rest.empty? && Integer === rest.first
perm = rest.shift
end
end
return mode, perm, rest
end
def OpenURI.open_uri(name, *rest) # :nodoc:
uri = URI::Generic === name ? name : URI.parse(name)
mode, _, rest = OpenURI.scan_open_optional_arguments(*rest)
options = rest.shift if !rest.empty? && Hash === rest.first
raise ArgumentError.new("extra arguments") if !rest.empty?
options ||= {}
OpenURI.check_options(options)
if /\Arb?(?:\Z|:([^:]+))/ =~ mode
encoding, = $1,Encoding.find($1) if $1
mode = nil
end
if options.has_key? :encoding
if !encoding.nil?
raise ArgumentError, "encoding specified twice"
end
encoding = Encoding.find(options[:encoding])
end
unless mode == nil ||
mode == 'r' || mode == 'rb' ||
mode == File::RDONLY
raise ArgumentError.new("invalid access mode #{mode} (#{uri.class} resource is read only.)")
end
io = open_loop(uri, options)
io.set_encoding(encoding) if encoding
if block_given?
begin
yield io
ensure
if io.respond_to? :close!
io.close! # Tempfile
else
io.close if !io.closed?
end
end
else
io
end
end
def OpenURI.open_loop(uri, options) # :nodoc:
proxy_opts = []
proxy_opts << :proxy_http_basic_authentication if options.include? :proxy_http_basic_authentication
proxy_opts << :proxy if options.include? :proxy
proxy_opts.compact!
if 1 < proxy_opts.length
raise ArgumentError, "multiple proxy options specified"
end
case proxy_opts.first
when :proxy_http_basic_authentication
opt_proxy, proxy_user, proxy_pass = options.fetch(:proxy_http_basic_authentication)
proxy_user = proxy_user.to_str
proxy_pass = proxy_pass.to_str
if opt_proxy == true
raise ArgumentError.new("Invalid authenticated proxy option: #{options[:proxy_http_basic_authentication].inspect}")
end
when :proxy
opt_proxy = options.fetch(:proxy)
proxy_user = nil
proxy_pass = nil
when nil
opt_proxy = true
proxy_user = nil
proxy_pass = nil
end
case opt_proxy
when true
find_proxy = lambda {|u| pxy = u.find_proxy; pxy ? [pxy, nil, nil] : nil}
when nil, false
find_proxy = lambda {|u| nil}
when String
opt_proxy = URI.parse(opt_proxy)
find_proxy = lambda {|u| [opt_proxy, proxy_user, proxy_pass]}
when URI::Generic
find_proxy = lambda {|u| [opt_proxy, proxy_user, proxy_pass]}
else
raise ArgumentError.new("Invalid proxy option: #{opt_proxy}")
end
uri_set = {}
buf = nil
while true
redirect = catch(:open_uri_redirect) {
buf = Buffer.new
uri.buffer_open(buf, find_proxy.call(uri), options)
nil
}
if redirect
if redirect.relative?
# Although it violates RFC2616, Location: field may have relative
# URI. It is converted to absolute URI using uri as a base URI.
redirect = uri + redirect
end
if !options.fetch(:redirect, true)
raise HTTPRedirect.new(buf.io.status.join(' '), buf.io, redirect)
end
unless OpenURI.redirectable?(uri, redirect)
raise "redirection forbidden: #{uri} -> #{redirect}"
end
if options.include? :http_basic_authentication
# send authentication only for the URI directly specified.
options = options.dup
options.delete :http_basic_authentication
end
uri = redirect
raise "HTTP redirection loop: #{uri}" if uri_set.include? uri.to_s
uri_set[uri.to_s] = true
else
break
end
end
io = buf.io
io.base_uri = uri
io
end
def OpenURI.redirectable?(uri1, uri2) # :nodoc:
# This test is intended to forbid a redirection from http://... to
# file:///etc/passwd, file:///dev/zero, etc. CVE-2011-1521
# https to http redirect is also forbidden intentionally.
# It avoids sending secure cookie or referer by non-secure HTTP protocol.
# (RFC 2109 4.3.1, RFC 2965 3.3, RFC 2616 15.1.3)
# However this is ad hoc. It should be extensible/configurable.
uri1.scheme.downcase == uri2.scheme.downcase ||
(/\A(?:http|ftp)\z/i =~ uri1.scheme && /\A(?:https?|ftp)\z/i =~ uri2.scheme)
end
def OpenURI.open_http(buf, target, proxy, options) # :nodoc:
if proxy
proxy_uri, proxy_user, proxy_pass = proxy
raise "Non-HTTP proxy URI: #{proxy_uri}" if proxy_uri.class != URI::HTTP
end
if target.userinfo
raise ArgumentError, "userinfo not supported. [RFC3986]"
end
header = {}
options.each {|k, v| header[k] = v if String === k }
require 'net/http'
klass = Net::HTTP
if URI::HTTP === target
# HTTP or HTTPS
if proxy
unless proxy_user && proxy_pass
proxy_user, proxy_pass = proxy_uri.userinfo.split(':') if proxy_uri.userinfo
end
if proxy_user && proxy_pass
klass = Net::HTTP::Proxy(proxy_uri.hostname, proxy_uri.port, proxy_user, proxy_pass)
else
klass = Net::HTTP::Proxy(proxy_uri.hostname, proxy_uri.port)
end
end
target_host = target.hostname
target_port = target.port
request_uri = target.request_uri
else
# FTP over HTTP proxy
target_host = proxy_uri.hostname
target_port = proxy_uri.port
request_uri = target.to_s
if proxy_user && proxy_pass
header["Proxy-Authorization"] =
'Basic ' + ["#{proxy_user}:#{proxy_pass}"].pack('m0')
end
end
http = proxy ? klass.new(target_host, target_port) : klass.new(target_host, target_port, nil)
if target.class == URI::HTTPS
require 'net/https'
http.use_ssl = true
http.verify_mode = options[:ssl_verify_mode] || OpenSSL::SSL::VERIFY_PEER
store = OpenSSL::X509::Store.new
if options[:ssl_ca_cert]
Array(options[:ssl_ca_cert]).each do |cert|
if File.directory? cert
store.add_path cert
else
store.add_file cert
end
end
else
store.set_default_paths
end
http.cert_store = store
end
if options.include? :read_timeout
http.read_timeout = options[:read_timeout]
end
if options.include? :open_timeout
http.open_timeout = options[:open_timeout]
end
resp = nil
http.start {
req = Net::HTTP::Get.new(request_uri, header)
if options.include? :http_basic_authentication
user, pass = options[:http_basic_authentication]
req.basic_auth user, pass
end
http.request(req) {|response|
resp = response
if options[:content_length_proc] && Net::HTTPSuccess === resp
if resp.key?('Content-Length')
options[:content_length_proc].call(resp['Content-Length'].to_i)
else
options[:content_length_proc].call(nil)
end
end
resp.read_body {|str|
buf << str
if options[:progress_proc] && Net::HTTPSuccess === resp
options[:progress_proc].call(buf.size)
end
str.clear
}
}
}
io = buf.io
io.rewind
io.status = [resp.code, resp.message]
resp.each_name {|name| buf.io.meta_add_field2 name, resp.get_fields(name) }
case resp
when Net::HTTPSuccess
when Net::HTTPMovedPermanently, # 301
Net::HTTPFound, # 302
Net::HTTPSeeOther, # 303
Net::HTTPTemporaryRedirect # 307
begin
loc_uri = URI.parse(resp['location'])
rescue URI::InvalidURIError
raise OpenURI::HTTPError.new(io.status.join(' ') + ' (Invalid Location URI)', io)
end
throw :open_uri_redirect, loc_uri
else
raise OpenURI::HTTPError.new(io.status.join(' '), io)
end
end
class HTTPError < StandardError
def initialize(message, io)
super(message)
@io = io
end
attr_reader :io
end
# Raised on redirection,
# only occurs when +redirect+ option for HTTP is +false+.
class HTTPRedirect < HTTPError
def initialize(message, io, uri)
super(message, io)
@uri = uri
end
attr_reader :uri
end
class Buffer # :nodoc: all
def initialize
@io = StringIO.new
@size = 0
end
attr_reader :size
StringMax = 10240
def <<(str)
@io << str
@size += str.length
if StringIO === @io && StringMax < @size
require 'tempfile'
io = Tempfile.new('open-uri')
io.binmode
Meta.init io, @io if Meta === @io
io << @io.string
@io = io
end
end
def io
Meta.init @io unless Meta === @io
@io
end
end
# Mixin for holding meta-information.
module Meta
def Meta.init(obj, src=nil) # :nodoc:
obj.extend Meta
obj.instance_eval {
@base_uri = nil
@meta = {} # name to string. legacy.
@metas = {} # name to array of strings.
}
if src
obj.status = src.status
obj.base_uri = src.base_uri
src.metas.each {|name, values|
obj.meta_add_field2(name, values)
}
end
end
# returns an Array that consists of status code and message.
attr_accessor :status
# returns a URI that is the base of relative URIs in the data.
# It may differ from the URI supplied by a user due to redirection.
attr_accessor :base_uri
# returns a Hash that represents header fields.
# The Hash keys are downcased for canonicalization.
# The Hash values are a field body.
# If there are multiple field with same field name,
# the field values are concatenated with a comma.
attr_reader :meta
# returns a Hash that represents header fields.
# The Hash keys are downcased for canonicalization.
# The Hash value are an array of field values.
attr_reader :metas
def meta_setup_encoding # :nodoc:
charset = self.charset
enc = nil
if charset
begin
enc = Encoding.find(charset)
rescue ArgumentError
end
end
enc = Encoding::ASCII_8BIT unless enc
if self.respond_to? :force_encoding
self.force_encoding(enc)
elsif self.respond_to? :string
self.string.force_encoding(enc)
else # Tempfile
self.set_encoding enc
end
end
def meta_add_field2(name, values) # :nodoc:
name = name.downcase
@metas[name] = values
@meta[name] = values.join(', ')
meta_setup_encoding if name == 'content-type'
end
def meta_add_field(name, value) # :nodoc:
meta_add_field2(name, [value])
end
# returns a Time that represents the Last-Modified field.
def last_modified
if vs = @metas['last-modified']
v = vs.join(', ')
Time.httpdate(v)
else
nil
end
end
# :stopdoc:
RE_LWS = /[\r\n\t ]+/n
RE_TOKEN = %r{[^\x00- ()<>@,;:\\"/\[\]?={}\x7f]+}n
RE_QUOTED_STRING = %r{"(?:[\r\n\t !#-\[\]-~\x80-\xff]|\\[\x00-\x7f])*"}n
RE_PARAMETERS = %r{(?:;#{RE_LWS}?#{RE_TOKEN}#{RE_LWS}?=#{RE_LWS}?(?:#{RE_TOKEN}|#{RE_QUOTED_STRING})#{RE_LWS}?)*}n
# :startdoc:
def content_type_parse # :nodoc:
vs = @metas['content-type']
# The last (?:;#{RE_LWS}?)? matches extra ";" which violates RFC2045.
if vs && %r{\A#{RE_LWS}?(#{RE_TOKEN})#{RE_LWS}?/(#{RE_TOKEN})#{RE_LWS}?(#{RE_PARAMETERS})(?:;#{RE_LWS}?)?\z}no =~ vs.join(', ')
type = $1.downcase
subtype = $2.downcase
parameters = []
$3.scan(/;#{RE_LWS}?(#{RE_TOKEN})#{RE_LWS}?=#{RE_LWS}?(?:(#{RE_TOKEN})|(#{RE_QUOTED_STRING}))/no) {|att, val, qval|
if qval
val = qval[1...-1].gsub(/[\r\n\t !#-\[\]-~\x80-\xff]+|(\\[\x00-\x7f])/n) { $1 ? $1[1,1] : $& }
end
parameters << [att.downcase, val]
}
["#{type}/#{subtype}", *parameters]
else
nil
end
end
# returns "type/subtype" which is MIME Content-Type.
# It is downcased for canonicalization.
# Content-Type parameters are stripped.
def content_type
type, *_ = content_type_parse
type || 'application/octet-stream'
end
# returns a charset parameter in Content-Type field.
# It is downcased for canonicalization.
#
# If charset parameter is not given but a block is given,
# the block is called and its result is returned.
# It can be used to guess charset.
#
# If charset parameter and block is not given,
# nil is returned except text type.
# In that case, "utf-8" is returned as defined by RFC6838 4.2.1
def charset
type, *parameters = content_type_parse
if pair = parameters.assoc('charset')
pair.last.downcase
elsif block_given?
yield
elsif type && %r{\Atext/} =~ type
"utf-8" # RFC6838 4.2.1
else
nil
end
end
# Returns a list of encodings in Content-Encoding field as an array of
# strings.
#
# The encodings are downcased for canonicalization.
def content_encoding
vs = @metas['content-encoding']
if vs && %r{\A#{RE_LWS}?#{RE_TOKEN}#{RE_LWS}?(?:,#{RE_LWS}?#{RE_TOKEN}#{RE_LWS}?)*}o =~ (v = vs.join(', '))
v.scan(RE_TOKEN).map {|content_coding| content_coding.downcase}
else
[]
end
end
end
# Mixin for HTTP and FTP URIs.
module OpenRead
# OpenURI::OpenRead#open provides `open' for URI::HTTP and URI::FTP.
#
# OpenURI::OpenRead#open takes optional 3 arguments as:
#
# OpenURI::OpenRead#open([mode [, perm]] [, options]) [{|io| ... }]
#
# OpenURI::OpenRead#open returns an IO-like object if block is not given.
# Otherwise it yields the IO object and return the value of the block.
# The IO object is extended with OpenURI::Meta.
#
# +mode+ and +perm+ are the same as Kernel#open.
#
# However, +mode+ must be read mode because OpenURI::OpenRead#open doesn't
# support write mode (yet).
# Also +perm+ is ignored because it is meaningful only for file creation.
#
# +options+ must be a hash.
#
# Each option with a string key specifies an extra header field for HTTP.
# I.e., it is ignored for FTP without HTTP proxy.
#
# The hash may include other options, where keys are symbols:
#
# [:proxy]
# Synopsis:
# :proxy => "http://proxy.foo.com:8000/"
# :proxy => URI.parse("http://proxy.foo.com:8000/")
# :proxy => true
# :proxy => false
# :proxy => nil
#
# If :proxy option is specified, the value should be String, URI,
# boolean or nil.
#
# When String or URI is given, it is treated as proxy URI.
#
# When true is given or the option itself is not specified,
# environment variable `scheme_proxy' is examined.
# `scheme' is replaced by `http', `https' or `ftp'.
#
# When false or nil is given, the environment variables are ignored and
# connection will be made to a server directly.
#
# [:proxy_http_basic_authentication]
# Synopsis:
# :proxy_http_basic_authentication =>
# ["http://proxy.foo.com:8000/", "proxy-user", "proxy-password"]
# :proxy_http_basic_authentication =>
# [URI.parse("http://proxy.foo.com:8000/"),
# "proxy-user", "proxy-password"]
#
# If :proxy option is specified, the value should be an Array with 3
# elements. It should contain a proxy URI, a proxy user name and a proxy
# password. The proxy URI should be a String, an URI or nil. The proxy
# user name and password should be a String.
#
# If nil is given for the proxy URI, this option is just ignored.
#
# If :proxy and :proxy_http_basic_authentication is specified,
# ArgumentError is raised.
#
# [:http_basic_authentication]
# Synopsis:
# :http_basic_authentication=>[user, password]
#
# If :http_basic_authentication is specified,
# the value should be an array which contains 2 strings:
# username and password.
# It is used for HTTP Basic authentication defined by RFC 2617.
#
# [:content_length_proc]
# Synopsis:
# :content_length_proc => lambda {|content_length| ... }
#
# If :content_length_proc option is specified, the option value procedure
# is called before actual transfer is started.
# It takes one argument, which is expected content length in bytes.
#
# If two or more transfers are performed by HTTP redirection, the
# procedure is called only once for the last transfer.
#
# When expected content length is unknown, the procedure is called with
# nil. This happens when the HTTP response has no Content-Length header.
#
# [:progress_proc]
# Synopsis:
# :progress_proc => lambda {|size| ...}
#
# If :progress_proc option is specified, the proc is called with one
# argument each time when `open' gets content fragment from network.
# The argument +size+ is the accumulated transferred size in bytes.
#
# If two or more transfer is done by HTTP redirection, the procedure
# is called only one for a last transfer.
#
# :progress_proc and :content_length_proc are intended to be used for
# progress bar.
# For example, it can be implemented as follows using Ruby/ProgressBar.
#
# pbar = nil
# open("http://...",
# :content_length_proc => lambda {|t|
# if t && 0 < t
# pbar = ProgressBar.new("...", t)
# pbar.file_transfer_mode
# end
# },
# :progress_proc => lambda {|s|
# pbar.set s if pbar
# }) {|f| ... }
#
# [:read_timeout]
# Synopsis:
# :read_timeout=>nil (no timeout)
# :read_timeout=>10 (10 second)
#
# :read_timeout option specifies a timeout of read for http connections.
#
# [:open_timeout]
# Synopsis:
# :open_timeout=>nil (no timeout)
# :open_timeout=>10 (10 second)
#
# :open_timeout option specifies a timeout of open for http connections.
#
# [:ssl_ca_cert]
# Synopsis:
# :ssl_ca_cert=>filename or an Array of filenames
#
# :ssl_ca_cert is used to specify CA certificate for SSL.
# If it is given, default certificates are not used.
#
# [:ssl_verify_mode]
# Synopsis:
# :ssl_verify_mode=>mode
#
# :ssl_verify_mode is used to specify openssl verify mode.
#
# [:ftp_active_mode]
# Synopsis:
# :ftp_active_mode=>bool
#
# <tt>:ftp_active_mode => true</tt> is used to make ftp active mode.
# Ruby 1.9 uses passive mode by default.
# Note that the active mode is default in Ruby 1.8 or prior.
#
# [:redirect]
# Synopsis:
# :redirect=>bool
#
# +:redirect+ is true by default. <tt>:redirect => false</tt> is used to
# disable all HTTP redirects.
#
# OpenURI::HTTPRedirect exception raised on redirection.
# Using +true+ also means that redirections between http and ftp are
# permitted.
#
def open(*rest, &block)
OpenURI.open_uri(self, *rest, &block)
end
# OpenURI::OpenRead#read([options]) reads a content referenced by self and
# returns the content as string.
# The string is extended with OpenURI::Meta.
# The argument +options+ is same as OpenURI::OpenRead#open.
def read(options={})
self.open(options) {|f|
str = f.read
Meta.init str, f
str
}
end
end
end
module URI
class HTTP
def buffer_open(buf, proxy, options) # :nodoc:
OpenURI.open_http(buf, self, proxy, options)
end
include OpenURI::OpenRead
end
class FTP
def buffer_open(buf, proxy, options) # :nodoc:
if proxy
OpenURI.open_http(buf, self, proxy, options)
return
end
require 'net/ftp'
path = self.path
path = path.sub(%r{\A/}, '%2F') # re-encode the beginning slash because uri library decodes it.
directories = path.split(%r{/}, -1)
directories.each {|d|
d.gsub!(/%([0-9A-Fa-f][0-9A-Fa-f])/) { [$1].pack("H2") }
}
unless filename = directories.pop
raise ArgumentError, "no filename: #{self.inspect}"
end
directories.each {|d|
if /[\r\n]/ =~ d
raise ArgumentError, "invalid directory: #{d.inspect}"
end
}
if /[\r\n]/ =~ filename
raise ArgumentError, "invalid filename: #{filename.inspect}"
end
typecode = self.typecode
if typecode && /\A[aid]\z/ !~ typecode
raise ArgumentError, "invalid typecode: #{typecode.inspect}"
end
# The access sequence is defined by RFC 1738
ftp = Net::FTP.new
ftp.connect(self.hostname, self.port)
ftp.passive = !options[:ftp_active_mode]
# todo: extract user/passwd from .netrc.
user = 'anonymous'
passwd = nil
user, passwd = self.userinfo.split(/:/) if self.userinfo
ftp.login(user, passwd)
directories.each {|cwd|
ftp.voidcmd("CWD #{cwd}")
}
if typecode
# xxx: typecode D is not handled.
ftp.voidcmd("TYPE #{typecode.upcase}")
end
if options[:content_length_proc]
options[:content_length_proc].call(ftp.size(filename))
end
ftp.retrbinary("RETR #{filename}", 4096) { |str|
buf << str
options[:progress_proc].call(buf.size) if options[:progress_proc]
}
ftp.close
buf.io.rewind
end
include OpenURI::OpenRead
end
end