xmlrpc/client.rb

Copyright (C) 2001, 2002 by Michael Neumann (neumann@s-direktnet.de)

Released under the same term of license as Ruby.

Classes

XMLRPC::Client

Synopsis

require "xmlrpc/client"

server = XMLRPC::Client.new("www.ruby-lang.org", "/RPC2", 80)
begin
  param = server.call("michael.add", 4, 5)
  puts "4 + 5 = #{param}"
rescue XMLRPC::FaultException => e
  puts "Error:"
  puts e.faultCode
  puts e.faultString
end

or

require "xmlrpc/client"

server = XMLRPC::Client.new("www.ruby-lang.org", "/RPC2", 80)
ok, param = server.call2("michael.add", 4, 5)
if ok then
  puts "4 + 5 = #{param}"
else
  puts "Error:"
  puts param.faultCode
  puts param.faultString
end

Description

Class XMLRPC::Client provides remote procedure calls to a XML-RPC server. After setting the connection-parameters with XMLRPC::Client.new which creates a new XMLRPC::Client instance, you can execute a remote procedure by sending the call or call2 message to this new instance. The given parameters indicate which method to call on the remote-side and of course the parameters for the remote procedure.

Class Methods

XMLRPC::Client.new( host=nil, path=nil, port=nil, proxy_host=nil, proxy_port=nil, user=nil, password=nil, use_ssl=false, timeout =nil)

Creates an object which represents the remote XML-RPC server on the given host host. If the server is CGI-based, path is the path to the CGI-script, which will be called, otherwise (in the case of a standalone server) path should be "/RPC2". port is the port on which the XML-RPC server listens. If proxy_host is given, then a proxy server listening at proxy_host is used. proxy_port is the port of the proxy server.

Default values for host, path and port are 'localhost', '/RPC2' and '80' respectively using SSL '443'.

If user and password are given, each time a request is send, a Authorization header is send. Currently only Basic Authentification is implemented no Digest.

If use_ssl is set to true, comunication over SSL is enabled. Note, that you need the SSL package from RAA installed.

Parameter timeout is the time to wait for a XML-RPC response, defaults to 30.

XMLRPC::Client.new2( uri, proxy=nil, timeout=nil)
uri

URI specifying protocol (http or https), host, port, path, user and password. Example: https://user:password@host:port/path

proxy

Is of the form "host:port".

timeout

Defaults to 30.

XMLRPC::Client.new3( hash={} )

Parameter hash has following case-insensitive keys:

Calls XMLRPC::Client.new with the corresponding values.

Instance Methods

XMLRPC::Client#call( method, *args )

Invokes the method named method with the parameters given by args on the XML-RPC server. The parameter method is converted into a String and should be a valid XML-RPC method-name. Each parameter of args must be of one of the following types, where Hash, Struct and Array can contain any of these listed types:

The method returns the return-value from the RPC *1. The type of the return-value is one of the above shown, only that a Bignum is only allowed when it fits in 32-bit and that a XML-RPC dateTime.iso8601 type is always returned as a XMLRPC::DateTime object and a Struct is never returned, only a Hash, the same for a Symbol, where always a String is returned. A XMLRPC::Base64 is returned as a String from xmlrpc4r version 1.6.1 on.

If the remote procedure returned a fault-structure, then a XMLRPC::FaultException exception is raised, which has two accessor-methods faultCode and faultString of type Integer and String.

XMLRPC::Client#call2( method, *args )

The difference between this method and call is, that this method do not raise a XMLRPC::FaultException exception. The method returns an array of two values. The first value indicates if the second value is a return-value (true) or an object of type XMLRPC::FaultException. Both are explained in call.

XMLRPC::Client#multicall( *methods )

You can use this method to execute several methods on a XMLRPC server which supports the multi-call extension. Example:

s.multicall(
  ['michael.add', 3, 4],
  ['michael.sub', 4, 5]
)
# => [7, -1]
XMLRPC::Client#multicall2( *methods )

Same as XMLRPC::Client#multicall, but returns like XMLRPC::Client#call2 two parameters instead of raising an XMLRPC::FaultException.

XMLRPC::Client#proxy( prefix, *args )

Returns an object of class XMLRPC::Client::Proxy, initialized with prefix and args. A proxy object returned by this method behaves like XMLRPC::Client#call, i.e. a call on that object will raise a XMLRPC::FaultException when a fault-structure is returned by that call.

XMLRPC::Client#proxy2( prefix, *args )

Almost the same like XMLRPC::Client#proxy only that a call on the returned XMLRPC::Client::Proxy object behaves like XMLRPC::Client#call2, i.e. a call on that object will return two parameters.

XMLRPC::Client#call_async(...)
XMLRPC::Client#call2_async(...)
XMLRPC::Client#multicall_async(...)
XMLRPC::Client#multicall2_async(...)
XMLRPC::Client#proxy_async(...)
XMLRPC::Client#proxy2_async(...)

In contrast to corresponding methods without "_async", these can be called concurrently and use for each request a new connection, where the non-asynchronous counterparts use connection-alive (one connection for all requests) if possible.

Note, that you have to use Threads to call these methods concurrently. The following example calls two methods concurrently:

Thread.new {
  p client.call_async("michael.add", 4, 5)
}

Thread.new {
  p client.call_async("michael.div", 7, 9)
}
XMLRPC::Client#timeout
XMLRPC::Client#user
XMLRPC::Client#password

Return the corresponding attributes.

XMLRPC::Client#timeout= (new_timeout)
XMLRPC::Client#user= (new_user)
XMLRPC::Client#password= (new_password)

Set the corresponding attributes.

XMLRPC::Client#set_writer( writer )

Sets the XML writer to use for generating XML output. Should be an instance of a class from module XMLRPC::XMLWriter. If this method is not called, then XMLRPC::Config::DEFAULT_WRITER is used.

XMLRPC::Client#set_parser( parser )

Sets the XML parser to use for parsing XML documents. Should be an instance of a class from module XMLRPC::XMLParser. If this method is not called, then XMLRPC::Config::DEFAULT_PARSER is used.

XMLRPC::Client::Proxy

Synopsis

require "xmlrpc/client"

server = XMLRPC::Client.new("www.ruby-lang.org", "/RPC2", 80)

michael  = server.proxy("michael")
michael2 = server.proxy("michael", 4)

# both calls should return the same value '9'.
p michael.add(4,5)
p michael2.add(5)

Description

Class XMLRPC::Client::Proxy makes XML-RPC calls look nicer! You can call any method onto objects of that class - the object handles method_missing and will forward the method call to a XML-RPC server. Don't use this class directly, but use instead method XMLRPC::Client#proxy or XMLRPC::Client#proxy2.

Class Methods

XMLRPC::Client::Proxy.new( server, prefix, args=[], meth=:call, delim="." )

Creates an object which provides method_missing.

server must be of type XMLRPC::Client, which is the XML-RPC server to be used for a XML-RPC call. prefix and delim will be prepended to the methodname called onto this object.

Parameter meth is the method (call, call2, call_async, call2_async) to use for a RPC.

args are arguments which are automatically given to every XML-RPC call before the arguments provides through method_missing.

Instance Methods

Every method call is forwarded to the XML-RPC server defined in new.

Note: Inherited methods from class Object cannot be used as XML-RPC names, because they get around method_missing.

History

$Id: client.rb,v 1.51 2003/04/08 15:14:22 mneumann Exp $

*1stands for Remote Procedure Call