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|
module Bundler
class Settings
# Class used to build the mirror set and then find a mirror for a given URI
#
# @param prober [Prober object, nil] by default a TCPSocketProbe, this object
# will be used to probe the mirror address to validate that the mirror replies.
class Mirrors
def initialize(prober = nil)
@all = Mirror.new
@prober = prober || TCPSocketProbe.new
@mirrors = {}
end
# Returns a mirror for the given uri.
#
# Depending on the uri having a valid mirror or not, it may be a
# mirror that points to the provided uri
def for(uri)
if @all.validate!(@prober).valid?
@all
else
fetch_valid_mirror_for(Settings.normalize_uri(uri))
end
end
def each
@mirrors.each do |k, v|
yield k, v.uri.to_s
end
end
def parse(key, value)
config = MirrorConfig.new(key, value)
if config.all?
mirror = @all
else
mirror = (@mirrors[config.uri] = @mirrors[config.uri] || Mirror.new)
end
config.update_mirror(mirror)
end
private
def fetch_valid_mirror_for(uri)
mirror = (@mirrors[URI(uri.to_s.downcase)] || Mirror.new(uri)).validate!(@prober)
mirror = Mirror.new(uri) unless mirror.valid?
mirror
end
end
# A mirror
#
# Contains both the uri that should be used as a mirror and the
# fallback timeout which will be used for probing if the mirror
# replies on time or not.
class Mirror
DEFAULT_FALLBACK_TIMEOUT = 0.1
attr_reader :uri, :fallback_timeout
def initialize(uri = nil, fallback_timeout = 0)
self.uri = uri
self.fallback_timeout = fallback_timeout
@valid = nil
end
def uri=(uri)
@uri = if uri.nil?
nil
else
URI(uri.to_s)
end
@valid = nil
end
def fallback_timeout=(timeout)
case timeout
when true, "true"
@fallback_timeout = DEFAULT_FALLBACK_TIMEOUT
when false, "false"
@fallback_timeout = 0
else
@fallback_timeout = timeout.to_i
end
@valid = nil
end
def ==(other)
!other.nil? && uri == other.uri && fallback_timeout == other.fallback_timeout
end
def valid?
return false if @uri.nil?
return @valid unless @valid.nil?
false
end
def validate!(probe = nil)
@valid = false if uri.nil?
if @valid.nil?
@valid = fallback_timeout == 0 || (probe || TCPSocketProbe.new).replies?(self)
end
self
end
end
# Class used to parse one configuration line
#
# Gets the configuration line and the value.
# This object provides a `update_mirror` method
# used to setup the given mirror value.
class MirrorConfig
attr_accessor :uri, :value
def initialize(config_line, value)
uri, fallback =
config_line.match(%r{^mirror\.(all|.+?)(\.fallback_timeout)?\/?$}).captures
@fallback = !fallback.nil?
@all = false
if uri == "all"
@all = true
else
@uri = Settings.normalize_uri(uri)
end
@value = value
end
def all?
@all
end
def update_mirror(mirror)
if @fallback
mirror.fallback_timeout = @value
else
mirror.uri = Settings.normalize_uri(@value)
end
end
end
# Class used for probing TCP availability for a given mirror.
class TCPSocketProbe
def replies?(mirror)
MirrorSockets.new(mirror).any? do |socket, address, timeout|
begin
socket.connect_nonblock(address)
rescue Errno::EINPROGRESS
wait_for_writtable_socket(socket, address, timeout)
rescue # Connection failed somehow, again
false
end
end
end
private
def wait_for_writtable_socket(socket, address, timeout)
if IO.select(nil, [socket], nil, timeout)
probe_writtable_socket(socket, address)
else # TCP Handshake timed out, or there is something dropping packets
false
end
end
def probe_writtable_socket(socket, address)
socket.connect_nonblock(address)
rescue Errno::EISCONN
true
rescue # Connection failed
false
end
end
end
# Class used to build the list of sockets that correspond to
# a given mirror.
#
# One mirror may correspond to many different addresses, both
# because of it having many dns entries or just because
# the network interface is both ipv4 and ipv5
class MirrorSockets
def initialize(mirror)
@timeout = mirror.fallback_timeout
@addresses = Socket.getaddrinfo(mirror.uri.host, mirror.uri.port).map do |address|
SocketAddress.new(address[0], address[3], address[1])
end
end
def any?
@addresses.any? do |address|
socket = Socket.new(Socket.const_get(address.type), Socket::SOCK_STREAM, 0)
socket.setsockopt(Socket::IPPROTO_TCP, Socket::TCP_NODELAY, 1)
value = yield socket, address.to_socket_address, @timeout
socket.close unless socket.closed?
value
end
end
end
# Socket address builder.
#
# Given a socket type, a host and a port,
# provides a method to build sockaddr string
class SocketAddress
attr_reader :type, :host, :port
def initialize(type, host, port)
@type = type
@host = host
@port = port
end
def to_socket_address
Socket.pack_sockaddr_in(@port, @host)
end
end
end
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