Re: Changing Resolv::DNS
From:
"Daniel Hobe" <daniel@...>
Date:
2004-05-05 20:41:21 UTC
List:
ruby-core #2847
I like this. Creates a more unified Resolv class.
> In article <200405011554.53670.daniel@nightrunner.com>,
> Daniel Hobe <daniel@nightrunner.com> writes:
>
>> Resolv::DNS.new('/etc/foo')
>> -or-
>> Resolv::DNS.new({nameserver=>['192.168.10.1','192.168.10.2'],
>> search=>['ruby-lang.org','ruby-doc.org'],
>> ndots => 2})
>
> I feel this initialization style is good enough.
>
> However I'd like to just change Config instead of defining a subclass.
>
> Index: lib/resolv.rb
> ===================================================================
> RCS file: /src/ruby/lib/resolv.rb,v
> retrieving revision 1.19
> diff -u -r1.19 resolv.rb
> --- lib/resolv.rb 23 Apr 2004 05:22:24 -0000 1.19
> +++ lib/resolv.rb 4 May 2004 07:26:35 -0000
> @@ -10,9 +10,10 @@
> Resolv.getaddress("www.ruby-lang.org")
> Resolv.getname("210.251.121.214")
>
> - dns = Resolv::DNS.new
> - dns.getresources("www.ruby-lang.org",
> Resolv::DNS::Resource::IN::A).collect {|r| r.address}
> - dns.getresources("ruby-lang.org",
> Resolv::DNS::Resource::IN::MX).collect {|r| [r.exchange.to_s,
> r.preference]}
> + Resolv::DNS.open {|dns|
> + dns.getresources("www.ruby-lang.org",
> Resolv::DNS::Resource::IN::A).collect {|r| r.address}
> + dns.getresources("ruby-lang.org",
> Resolv::DNS::Resource::IN::MX).collect {|r| [r.exchange.to_s,
> r.preference]}
> + }
>
> == Resolv class
>
> @@ -57,10 +58,17 @@
> DNS stub resolver.
>
> === class methods
> ---- Resolv::DNS.new(resolv_conf='/etc/resolv.conf')
> +--- Resolv::DNS.new(config_info=nil)
>
> ---- Resolv::DNS.open(resolv_conf='/etc/resolv.conf')
> ---- Resolv::DNS.open(resolv_conf='/etc/resolv.conf') {|dns| ...}
> + ((|config_info|)) should be nil, a string or a hash.
> + If nil is given, /etc/resolv.conf and platform specific information
> is used.
> + If a string is given, it should be a filename which format is same as
> /etc/resolv.conf.
> + If a hash is given, it may contains information for nameserver,
> search and ndots as follows.
> +
> + Resolv::DNS.new({:nameserver=>["210.251.121.21"],
> :search=>["ruby-lang.org"], :ndots=>1})
> +
> +--- Resolv::DNS.open(config_info=nil)
> +--- Resolv::DNS.open(config_info=nil) {|dns| ...}
>
> === methods
> --- Resolv::DNS#close
> @@ -369,9 +377,9 @@
> end
> end
>
> - def initialize(config="/etc/resolv.conf")
> + def initialize(config_info=nil)
> @mutex = Mutex.new
> - @config = Config.new(config)
> + @config = Config.new(config_info)
> @initialized = nil
> end
>
> @@ -704,47 +712,81 @@
> end
>
> class Config
> - def initialize(filename="/etc/resolv.conf")
> + def initialize(config_info=nil)
> @mutex = Mutex.new
> - @filename = filename
> + @config_info = config_info
> @initialized = nil
> end
>
> + def Config.parse_resolv_conf(filename)
> + nameserver = []
> + search = nil
> + ndots = 1
> + open(filename) {|f|
> + f.each {|line|
> + line.sub!(/[#;].*/, '')
> + keyword, *args = line.split(/\s+/)
> + args.each { |arg|
> + arg.untaint
> + }
> + next unless keyword
> + case keyword
> + when 'nameserver'
> + nameserver += args
> + when 'domain'
> + search = [args[0]]
> + when 'search'
> + search = args
> + end
> + }
> + }
> + return { :nameserver => nameserver, :search => search, :ndots =>
> ndots }
> + end
> +
> + def Config.default_config_hash(filename="/etc/resolv.conf")
> + if File.exist? filename
> + config_hash = Config.parse_resolv_conf(filename)
> + else
> + if /mswin32|cygwin|mingw|bccwin/ =~ RUBY_PLATFORM
> + search, nameserver = Win32::Resolv.get_resolv_info
> + config_hash = {}
> + config_hash[:nameserver] = nameserver if nameserver
> + config_hash[:search] = [search] if search
> + end
> + end
> + config_hash
> + end
> +
> def lazy_initialize
> @mutex.synchronize {
> unless @initialized
> @nameserver = []
> @search = nil
> @ndots = 1
> - begin
> - open(@filename) {|f|
> - f.each {|line|
> - line.sub!(/[#;].*/, '')
> - keyword, *args = line.split(/\s+/)
> - args.each { |arg|
> - arg.untaint
> - }
> - next unless keyword
> - case keyword
> - when 'nameserver'
> - @nameserver += args
> - when 'domain'
> - @search = [Label.split(args[0])]
> - when 'search'
> - @search = args.map {|arg| Label.split(arg)}
> - end
> - }
> - }
> - rescue Errno::ENOENT
> - if /mswin32|cygwin|mingw|bccwin/ =~ RUBY_PLATFORM
> - search, nameserver = Win32::Resolv.get_resolv_info
> - @search = [search] if search
> - @nameserver = nameserver if nameserver
> + case @config_info
> + when nil
> + config_hash = Config.default_config_hash
> + when String
> + config_hash = Config.parse_resolv_conf(@config_info)
> + when Hash
> + config_hash = @config_info.dup
> + if String === config_hash[:nameserver]
> + config_hash[:nameserver] = [config_hash[:nameserver]]
> end
> + if String === config_hash[:search]
> + config_hash[:search] = [config_hash[:search]]
> + end
> + else
> + raise ArgumentError.new("invalid resolv configuration:
> #{@config_info.inspect}")
> end
> + @nameserver = config_hash[:nameserver] if
> config_hash.include? :nameserver
> + @search = config_hash[:search] if config_hash.include?
> :search
> + @ndots = config_hash[:ndots] if config_hash.include? :ndots
>
> @nameserver = ['0.0.0.0'] if @nameserver.empty?
> - unless @search
> + if @search
> + @search = @search.map {|arg| Label.split(arg) }
> + else
> hostname = Socket.gethostname
> if /\./ =~ hostname
> @search = [Label.split($')]
> @@ -752,6 +794,21 @@
> @search = [[]]
> end
> end
> +
> + if !@nameserver.kind_of?(Array) ||
> + !@nameserver.all? {|ns| String === ns }
> + raise ArgumentError.new("invalid nameserver config:
> #{@nameserver.inspect}")
> + end
> +
> + if !@search.kind_of?(Array) ||
> + !@search.all? {|ls| ls.all? {|l| Label::Str === l } }
> + raise ArgumentError.new("invalid search config:
> #{@search.inspect}")
> + end
> +
> + if !@ndots.kind_of?(Integer)
> + raise ArgumentError.new("invalid ndots config:
> #{@ndots.inspect}")
> + end
> +
> @initialized = true
> end
> }
> --
> Tanaka Akira
>
>
>
--
Daniel Hobe <daniel@nightrunner.com>