the erb way

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binding

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binding¤ò»ØÄê¤¹¤ë¤³¤È¤Ç¡¢Ç¤°Õ¤Î¥¹¥³¡¼¥×¤ÇeRuby¥¹¥¯¥ê¥×¥È¤ò¼Â¹Ô¤Ç¤¡¢ eRuby¤ÎÉôÉÊ²½¤òÍÆ°×¤Ë¤·¤Þ¤¹¡£

binding¤òÍøÍÑ¤·¤¿Îã¤ò¼¨¤·¤Þ¤¹¡£

require 'erb'

class Foo
  SCRIPT = <<EOS
<h1><%= @name %></h1>
<ul>
<% ary.each do |x|%>
<li><%= x %></li>
<% end %>
</ul>
EOS
  def initialize(name)
    @name = name
    @erb = ERB.new(SCRIPT)
  end

  def foo(ary)
    @erb.result(binding)
  end
end

it = Foo.new('foo')
puts it.foo([1,2,'<dia>'])

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ERB::Util

ERB::Util¤Ïhtml¤ÎÀ¸À®¤Ê¤É¤ÇÊØÍø¤ÊÆó¤Ä¤Î¥á¥½¥Ã¥É¤òÄêµÁ¤·¤Æ¤¢¤ë¥â¥¸¥å¡¼¥ë¤Ç¤¹¡£ include¤·¤Æ»ÈÍÑ¤·¤Þ¤¹¡£

ERB::Util.html_escape(s)
ERB::Util.h(s): HTML¤Î &"<> ¤ò¥¨¥¹¥±¡¼¥×¤¹¤ë¡£
ERB::Util.url_encode(s)
ERB::Util.u(s): Ê¸»úÎó¤òURL¥¨¥ó¥³¡¼¥É¤¹¤ë¡£

Àè¤Û¤É¤Î¥¹¥¯¥ê¥×¥È¤Ë¤ÏÌäÂê¤¬¤¢¤Ã¤Æ¡¢@name¤äary¤ÎÆâÍÆ¤Ë Ãí°Õ¤òÊ§¤Ã¤Æ¤¤¤Þ¤»¤ó¡£HTML¥¨¥¹¥±¡¼¥×¤ò¤·¤Ê¤¬¤é½ÐÎÏ¤¹¤ë¤è¤¦¤Ë ÊÑ¹¹¤·¤Æ¤ß¤Þ¤·¤ç¤¦¡£

require 'erb'

class Foo
  include ERB::Util

  SCRIPT = <<EOS
<h1><%=h @name %></h1>
<ul>
<% ary.each do |x|%>
<li><%=h x %></li>
<% end %>
</ul>
EOS
  def initialize(name)
    @name = name
    @erb = ERB.new(SCRIPT)
  end

  def foo(ary)
    @erb.result(binding)
  end
end

it = Foo.new('foo')
puts it.foo([1,2,'<dia>'])

<%=h @name %>¤ä<%=h x %>¤¬HTML¥¨¥¹¥±¡¼¥×¤·¤Æ¤¤¤ëÉôÊ¬¤Ç¤¹¡£

<%=h ... %>

<%= h(...) %>

def_method

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ERB¤ò·«¤êÊÖ¤·¼Â¹Ô¤¹¤ë¾ì¹ç¤Ê¤É¡¢eval()¤Î¹Ô¤Ê¤¦¥¹¥¯¥ê¥×¥È¤Î¥Ñ¡¼¥º½èÍý¤Î ¥³¥¹¥È¤òÀáÌó¤Ç¤¤ë¤«¤â¤·¤ì¤Þ¤»¤ó¡£

ERB#def_method(mod, methodname, fname='(ERB)')

ÊÑ´¹¤·¤¿Ruby¥¹¥¯¥ê¥×¥È¤ò¥á¥½¥Ã¥É¤È¤·¤ÆÄêµÁ¤¹¤ë¡£ ÄêµÁÀè¤Î¥â¥¸¥å¡¼¥ë¤Ïmod¤Ç»ØÄê¤·¡¢¥á¥½¥Ã¥ÉÌ¾¤Ïmethodname¤Ç»ØÄê¤¹¤ë¡£ fname¤Ï¥¹¥¯¥ê¥×¥È¤òÄêµÁ¤¹¤ëºÝ¤Î¥Õ¥¡¥¤¥ëÌ¾¤Ç¤¢¤ë¡£¼ç¤Ë¥¨¥é¡¼»þ¤Ë³èÌö¤¹¤ë¡£

erb = ERB.new(script)
erb.def_method(MyClass, 'foo(bar)', 'foo.erb')

ERB::DefMethod.def_erb_method(methodname, erb)

self¤Ëerb¤Î¥¹¥¯¥ê¥×¥È¤ò¥á¥½¥Ã¥É¤Æ¤·¤ÆÄêµÁ¤¹¤ë¡£¥á¥½¥Ã¥ÉÌ¾¤Ïmethodname¤Ç»ØÄê¤¹¤ë¡£ self¤¬Ê¸»úÎó¤Î»þ¡¢¤½¤Î¥Õ¥¡¥¤¥ë¤òÆÉ¤ß¹þ¤ßERB¤ÇÊÑ´¹¤·¤¿¤Î¤Á¡¢¥á¥½¥Ã¥É¤È¤·¤ÆÄêµÁ¤¹¤ë¡£

class Writer
  extend ERB::DefMethod
  def_erb_method('to_html', 'writer.erb')
  ...
end
...
puts writer.to_html

require 'erb'

class Foo
  include ERB::Util

  SCRIPT = <<EOS
<h1><%=h @name %></h1>
<ul>
<% ary.each do |x|%>
<li><%=h x %></li>
<% end %>
</ul>
EOS

  ERB.new(SCRIPT).def_method(self, 'foo(ary)')

  def initialize(name)
    @name = name
  end
end

it = Foo.new('foo')
puts it.foo([1,2,'<dia>'])

¥á¥½¥Ã¥Éfoo¤ÎÄêµÁ¤Ê¤¯¤Ê¤ê¡¢Âå¤ï¤ê¤Ëdef_method(self, 'foo(ary)')¤È¤Ê¤ê¤Þ¤·¤¿¡£

¤µ¤é¤ËRuby¥¹¥¯¥ê¥×¥È¤ÈeRuby¥¹¥¯¥ê¥×¥È¤Î¥Õ¥¡¥¤¥ë¤òÊ¬³ä¤·¤Æ¤ß¤Þ¤¹¡£

¤Þ¤ºeRuby¥¹¥¯¥ê¥×¥È(foo.erb)¤ò¼¨¤·¤Þ¤¹¡£ Äê¿ôFoo::SCRIPT¤¬¤½¤Î¤Þ¤ÞÆþ¤Ã¤Æ¤¤¤Þ¤¹¡£

<h1><%=h @name %></h1>
<ul>
<% ary.each do |x|%>
<li><%=h x %></li>
<% end %>
</ul>

¼¡¤ËRuby¥¹¥¯¥ê¥×¥È¤ò¼¨¤·¤Þ¤¹¡£

require 'erb'

class Foo
  include ERB::Util
  extend ERB::DefMethod

  def_erb_method('foo(ary)', 'foo.erb')

  def initialize(name)
    @name = name
  end
end

it = Foo.new('foo')
puts it.foo([1,2,'<dia>'])

¤Ï¤¸¤á¤Ë¡¢ERB::DefMethod¤òextend¤·¤ÆFoo¥¯¥é¥¹¤Çdef_erb_method ¤Ç¤¤ë¤è¤¦¤Ë¤·¤Þ¤¹¡£

extend ERB::DefMethod

¤Ä¤Å¤¤¤Æ def_erb_method ¤Ç¥á¥½¥Ã¥É¤òÄêµÁ¤·¤Þ¤¹¡£ ºÇ½é¤Î°ú¿ô¤Ï¥á¥½¥Ã¥ÉÌ¾¤È²¾°ú¿ô¤Ç¤¹¡£ ÆóÈÖÌÜ¤Î¥á¥½¥Ã¥É¤ÏeRuby¥¹¥¯¥ê¥×¥È¤Î¥Õ¥¡¥¤¥ëÌ¾¤Ç¤¹¡£

Play with dRuby

dRuby¤ò»È¤Ã¤¿¥µ¡¼¥Ð¤ÈCGI¤Î¹½À®¤ÇERb¤ò»È¤Ã¤Æ¤ß¤Þ¤·¤ç¤¦¡£

¤´¤¯´ÊÃ±¤ÊWeb¥Á¥ã¥Ã¥ÈÉ÷¤Ê¤â¤Î
È¯¸À¤È°ì½ï¤Ë¥¯¥é¥¤¥¢¥ó¥È¤ÎIP¥¢¥É¥ì¥¹¤È»þ¹ï¤òÉ½¼¨¤¹¤ë
120ÉÃ¤¿¤Ã¤¿È¯¸À¤Ï¾Ã¤¨¤Æ¤·¤Þ¤¦
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dRuby¤Ë¤è¤ë¥µ¡¼¥Ðknock_s.rb¤ÈCGI¥¤¥ó¥¿¡¼¥Õ¥§¥¤¥¹knock.rb¤Ç¹½À®¤¹¤ë

¤Þ¤º¡¢¼ç½èÍý¤Ç¤¢¤ëknock_s.rb¤ò¸«¤Æ¤ß¤Þ¤¹¡£ KnockPage¤È¤¤¤¦Äê¿ô¤ÇeRuby¥¹¥¯¥ê¥×¥È¤òÄêµÁ¤·¤Æ¤¤¤Þ¤¹¡£ KnockWriter¤¬¥Ú¡¼¥¸¤òÀ¸À®¤¹¤ë¥¯¥é¥¹¤Ç¡¢KnockPage¤«¤é¼¡¤Î¤è¤¦¤Ë¥á¥½¥Ã¥É¤òÄêµÁ¤·¤Æ¤¤¤Þ¤¹¡£

ERB.new(KnockPage).def_method(self, "to_html")

knock_s.rb¤ÎÁ´ÂÎ¤ÎÎ®¤ì¤Ï¤è¤¯¸«¤«¤±¤ëdRuby¤Î¥×¥í¥°¥é¥à¤Ê¤Î¤Ç²òÀâ¤Ï¾ÊÎ¬¤·¤Þ¤¹¡£

CGI¤ò¼Â¹Ô¤¹¤ëÁ°¤Ë¡¢knock_s.rb¤òµ¯Æ°¤·¤Æ¤ª¤«¤Ê¤¯¤Æ¤Ï¤Ê¤ê¤Þ¤»¤ó¡£

% cat knock_s.rb
require 'drb/drb'
require 'erb'
require 'monitor'

class Knock
  def initialize(host, str)
    @host = host
    @str = str
    @time = Time.now
  end
  attr_reader :host, :str, :time
end

class KnockHistory
  include MonitorMixin

  def initialize(expire=120)
    super()
    @history = []
    @expire = expire
    @keeper = make_keeper
  end

  def add(host, str)
    synchronize do
      @history.push(Knock.new(host, str))
    end
    true
  end

  def each(&block)
    synchronize do
      @history.each(&block)
    end
  end

  private
  def forget
    time = Time.now - @expire
    synchronize do
      while (knock = @history[0])
        return if knock.time > time
        @history.shift
      end
    end
  end

  def make_keeper
    Thread.new do 
      loop do
	       sleep 5
        forget
      end
    end
  end
end

KnockPage = <<EOP
<ul>
<% @history.each do |k| %>
<li>
<%=h k.host %>(<%= k.time.strftime("%H:%M:%S") %>): <%=h k.str %>
</li>
<% end %>
</ul>
<form action="knock.rb" method="post">
<input type="text" name="knock" />
<input type="submit" name="send" value="send" />
</form>
EOP

class KnockWriter
  include DRbUndumped
  include ERB::Util

  def initialize(history)
    @history = history
  end

  def add(host, str)
    @history.add(host, str)
  end

  ERB.new(KnockPage).def_method(self, "to_html")
end

knock = KnockHistory.new
writer = KnockWriter.new(knock)

DRb.start_service('druby://localhost:8411', writer)
gets

¼¡¤ÏCGI¥¤¥ó¥¿¡¼¥Õ¥§¥¤¥¹¤Îknock.rb¤Ç¤¹¡£ ´Î¿´¤Ê½èÍý¤òknock_s.rb¤Î¥×¥í¥»¥¹¤ËÇ¤¤»¤Æ¤¤¤ë¤Î¤Ç »Å»ö¤¬¤¢¤Þ¤ê¤¢¤ê¤Þ¤»¤ó¡£

CGI¤Î¥ê¥¯¥¨¥¹¥È¤«¤éREMOTE_HOST¤ÈÈ¯¸À¤ò¼è¤ê½Ð¤·¤Æ knock¥µ¡¼¥Ð¤ØÁ÷¤ê¤Þ¤¹¡£ ¤½¤Î¸å¡¢knock.to_html¤Ë¤è¤Ã¤Æ¥Ú¡¼¥¸ËÜÂÎ¤Îbody¤ò¼èÆÀ¤·¤Æ¥Ú¡¼¥¸¤òÁÈ¤ßÎ©¤Æ¤Þ¤¹¡£

% cat knock.rb
#!/usr/local/bin/ruby
require 'drb/drb'
require 'cgi'

cgi = CGI.new('html3')

DRb.start_service
knock = DRbObject.new(nil, 'druby://localhost:8411')

str ,= cgi['knock']

if str && str.size > 0
  host = cgi.remote_host || cgi.remote_addr || 'unknown'
  knock.add(host, str) 
end

cgi.out {
  cgi.html() {
    cgi.head { 
      cgi.title { 'Knock' } +
      '<meta http-equiv="refresh" content="15; url=knock.rb" />'
    } + cgi.body { knock.to_html }
  }
}