library xmlrpc/server

要約

XML-RPC サーバのためのライブラリです。

CGI-based Server

There are also two ways to define handler, the first is like C/PHP, the second like Java, of course both ways can be mixed:

C/PHP-like (handler functions)

require "xmlrpc/server"

s = XMLRPC::CGIServer.new

s.add_handler("sample.sumAndDifference") do |a,b|
  { "sum" => a + b, "difference" => a - b }
end

s.serve

Java-like (handler classes)

require "xmlrpc/server"

s = XMLRPC::CGIServer.new

class MyHandler
  def sumAndDifference(a, b)
    { "sum" => a + b, "difference" => a - b }
  end
end

# NOTE: Security Hole (read below)!!!
s.add_handler("sample", MyHandler.new)
s.serve

To return a fault-structure you have to raise an FaultException e.g.:

raise XMLRPC::FaultException.new(3, "division by Zero")

Security Note

From Brian Candler:

Above code sample has an extremely nasty security hole, in that you can now call
any method of 'MyHandler' remotely, including methods inherited from Object
and Kernel! For example, in the client code, you can use

  puts server.call("sample.send","`","ls")

(backtick being the method name for running system processes). Needless to
say, 'ls' can be replaced with something else.

The version which binds proc objects (or the version presented below in the next section)
doesn't have this problem, but people may be tempted to use the second version because it's
so nice and 'Rubyesque'. I think it needs a big red disclaimer.

From Michael:

A solution is to undef insecure methods or to use XMLRPC::iPIMethods as shown below:

class MyHandler
  def sumAndDifference(a, b)
    { "sum" => a + b, "difference" => a - b }
  end
end

# ... server initialization ...

s.add_handler(XMLRPC::iPIMethods("sample"), MyHandler.new)

# ...

This adds only public instance methods explicitly declared in class MyHandler (and not those inherited from any other class).

With interface declarations

Code sample from the book Ruby Developer's Guide:

require "xmlrpc/server"

class Num
  INTERFACE = XMLRPC::interface("num") {
    meth 'int add(int, int)', 'Add two numbers', 'add'
    meth 'int div(int, int)', 'Divide two numbers'
  }

  def add(a, b) a + b end
  def div(a, b) a / b end
end


s = XMLRPC::CGIServer.new
s.add_handler(Num::INTERFACE, Num.new)
s.serve

Standalone server

Same as CGI-based server, only that the line

server = XMLRPC::CGIServer.new

must be changed to

server = XMLRPC::Server.new(8080)

if you want a server listening on port 8080. The rest is the same.