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In Files

  • drb/drb.rb
  • drb/invokemethod.rb

DRb::DRbServer

Class representing a drb server instance.

A DRbServer must be running in the local process before any incoming dRuby calls can be accepted, or any local objects can be passed as dRuby references to remote processes, even if those local objects are never actually called remotely. You do not need to start a DRbServer in the local process if you are only making outgoing dRuby calls passing marshalled parameters.

Unless multiple servers are being used, the local DRbServer is normally started by calling DRb.start_service.

Constants

INSECURE_METHOD

List of insecure methods.

These methods are not callable via dRuby.

Attributes

config[R]

The configuration of this DRbServer

front[R]

The front object of the DRbServer.

This object receives remote method calls made on the server’s URI alone, with an object id.

safe_level[R]
thread[R]

The main thread of this DRbServer.

This is the thread that listens for and accepts connections from clients, not that handles each client’s request-response session.

uri[R]

The URI of this DRbServer.

Public Class Methods

default_acl(acl) click to toggle source

Set the default value for the :acl option.

See new(). The initial default value is nil.

 
               # File drb/drb.rb, line 1248
def self.default_acl(acl)
  @@acl = acl
end
            
default_argc_limit(argc) click to toggle source

Set the default value for the :argc_limit option.

See new(). The initial default value is 256.

 
               # File drb/drb.rb, line 1234
def self.default_argc_limit(argc)
  @@argc_limit = argc
end
            
default_id_conv(idconv) click to toggle source

Set the default value for the :id_conv option.

See new(). The initial default value is a DRbIdConv instance.

 
               # File drb/drb.rb, line 1255
def self.default_id_conv(idconv)
  @@idconv = idconv
end
            
default_load_limit(sz) click to toggle source

Set the default value for the :load_limit option.

See new(). The initial default value is 25 MB.

 
               # File drb/drb.rb, line 1241
def self.default_load_limit(sz)
  @@load_limit = sz
end
            
default_safe_level(level) click to toggle source
 
               # File drb/drb.rb, line 1259
def self.default_safe_level(level)
  @@safe_level = level
end
            
new(uri=nil, front=nil, config_or_acl=nil) click to toggle source

Create a new DRbServer instance.

uri is the URI to bind to. This is normally of the form 'druby://<hostname>:<port>' where <hostname> is a hostname of the local machine. If nil, then the system's default hostname will be bound to, on a port selected by the system; these value can be retrieved from the uri attribute. 'druby:' specifies the default dRuby transport protocol: another protocol, such as 'drbunix:', can be specified instead.

front is the front object for the server, that is, the object to which remote method calls on the server will be passed. If nil, then the server will not accept remote method calls.

If config_or_acl is a hash, it is the configuration to use for this server. The following options are recognised:

:idconv

an id-to-object conversion object. This defaults to an instance of the class DRb::DRbIdConv.

:verbose

if true, all unsuccessful remote calls on objects in the server will be logged to $stdout. false by default.

:tcp_acl

the access control list for this server. See the ACL class from the main dRuby distribution.

:load_limit

the maximum message size in bytes accepted by the server. Defaults to 25 MB (26214400).

:argc_limit

the maximum number of arguments to a remote method accepted by the server. Defaults to 256.

The default values of these options can be modified on a class-wide basis by the class methods default_argc_limit, default_load_limit, default_acl, default_id_conv, and verbose=

If config_or_acl is not a hash, but is not nil, it is assumed to be the access control list for this server. See the :tcp_acl option for more details.

If no other server is currently set as the primary server, this will become the primary server.

The server will immediately start running in its own thread.

 
               # File drb/drb.rb, line 1330
def initialize(uri=nil, front=nil, config_or_acl=nil)
  if Hash === config_or_acl
    config = config_or_acl.dup
  else
    acl = config_or_acl || @@acl
    config = {
      :tcp_acl => acl
    }
  end

  @config = self.class.make_config(config)

  @protocol = DRbProtocol.open_server(uri, @config)
  @uri = @protocol.uri

  @front = front
  @idconv = @config[:idconv]
  @safe_level = @config[:safe_level]

  @grp = ThreadGroup.new
  @thread = run

  DRb.regist_server(self)
end
            
verbose() click to toggle source

Get the default value of the :verbose option.

 
               # File drb/drb.rb, line 1271
def self.verbose
  @@verbose
end
            
verbose=(on) click to toggle source

Set the default value of the :verbose option.

See new(). The initial default value is false.

 
               # File drb/drb.rb, line 1266
def self.verbose=(on)
  @@verbose = on
end
            

Public Instance Methods

alive?() click to toggle source

Is this server alive?

 
               # File drb/drb.rb, line 1387
def alive?
  @thread.alive?
end
            
check_insecure_method(obj, msg_id) click to toggle source

Check that a method is callable via dRuby.

obj is the object we want to invoke the method on. msg_id is the method name, as a Symbol.

If the method is an insecure method (see insecure_method?) a SecurityError is thrown. If the method is private or undefined, a NameError is thrown.

 
               # File drb/drb.rb, line 1470
def check_insecure_method(obj, msg_id)
  return true if Proc === obj && msg_id == :__drb_yield
  raise(ArgumentError, "#{any_to_s(msg_id)} is not a symbol") unless Symbol == msg_id.class
  raise(SecurityError, "insecure method `#{msg_id}'") if insecure_method?(msg_id)
  
  if obj.private_methods.include?(msg_id.to_s)
    desc = any_to_s(obj)
    raise NoMethodError, "private method `#{msg_id}' called for #{desc}"
  elsif obj.protected_methods.include?(msg_id.to_s)
    desc = any_to_s(obj)
    raise NoMethodError, "protected method `#{msg_id}' called for #{desc}"
  else
    true
  end
end
            
stop_service() click to toggle source

Stop this server.

 
               # File drb/drb.rb, line 1392
def stop_service
  DRb.remove_server(self)
  if  Thread.current['DRb'] && Thread.current['DRb']['server'] == self
    Thread.current['DRb']['stop_service'] = true
  else
    @thread.kill
  end
end
            
to_id(obj) click to toggle source

Convert a local object to a dRuby reference.

 
               # File drb/drb.rb, line 1409
def to_id(obj)
  return nil if obj.__id__ == front.__id__
  @idconv.to_id(obj)
end
            
to_obj(ref) click to toggle source

Convert a dRuby reference to the local object it refers to.

 
               # File drb/drb.rb, line 1402
def to_obj(ref)
  return front if ref.nil?
  return front[ref.to_s] if DRbURIOption === ref
  @idconv.to_obj(ref)
end
            
verbose() click to toggle source

Get whether the server is in verbose mode.

In verbose mode, failed calls are logged to stdout.

 
               # File drb/drb.rb, line 1384
def verbose; @config[:verbose]; end
            
verbose=(v) click to toggle source

Set whether to operate in verbose mode.

In verbose mode, failed calls are logged to stdout.

 
               # File drb/drb.rb, line 1379
def verbose=(v); @config[:verbose]=v; end
            

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