Class: DRb::DRbServer

Inherits:
Object
  • Object
show all
Defined in:
lib/drb/drb.rb,
lib/drb/invokemethod.rb

Overview

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.

Defined Under Namespace

Modules: InvokeMethod18Mixin Classes: InvokeMethod

Constant Summary collapse

@@acl = 
nil
@@idconv = 
DRbIdConv.new
@@secondary_server = 
nil
@@argc_limit = 
256
@@load_limit = 
256 * 102400
@@verbose = 
false
@@safe_level = 
0

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(uri = nil, front = nil, config_or_acl = nil) ⇒ DRbServer

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.

:safe_level

The safe level of the DRbServer. The attribute sets $SAFE for methods performed in the main_loop. Defaults to 0.

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.



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# File 'lib/drb/drb.rb', line 1361

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
  @exported_uri = [@uri]

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

  @grp = ThreadGroup.new
  @thread = run

  DRb.regist_server(self)
end

Instance Attribute Details

#config ⇒ Object (readonly)

The configuration of this DRbServer



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# File 'lib/drb/drb.rb', line 1404

def config
  @config
end

#front ⇒ Object (readonly)

The front object of the DRbServer.

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



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# File 'lib/drb/drb.rb', line 1401

def front
  @front
end

#safe_level ⇒ Object (readonly)

The safe level for this server. This is a number corresponding to $SAFE.

The default safe_level is 0



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# File 'lib/drb/drb.rb', line 1410

def safe_level
  @safe_level
end

#thread ⇒ Object (readonly)

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.



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# File 'lib/drb/drb.rb', line 1395

def thread
  @thread
end

#uri ⇒ Object (readonly)

The URI of this DRbServer.



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# File 'lib/drb/drb.rb', line 1388

def uri
  @uri
end

Class Method Details

.default_acl(acl) ⇒ Object

Set the default access control list to acl. The default ACL is nil.

See also DRb::ACL and #new()



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# File 'lib/drb/drb.rb', line 1273

def self.default_acl(acl)
  @@acl = acl
end

.default_argc_limit(argc) ⇒ Object

Set the default value for the :argc_limit option.

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



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# File 'lib/drb/drb.rb', line 1259

def self.default_argc_limit(argc)
  @@argc_limit = argc
end

.default_id_conv(idconv) ⇒ Object

Set the default value for the :id_conv option.

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



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# File 'lib/drb/drb.rb', line 1280

def self.default_id_conv(idconv)
  @@idconv = idconv
end

.default_load_limit(sz) ⇒ Object

Set the default value for the :load_limit option.

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



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# File 'lib/drb/drb.rb', line 1266

def self.default_load_limit(sz)
  @@load_limit = sz
end

.default_safe_level(level) ⇒ Object

Set the default safe level to level. The default safe level is 0

See #new for more information.



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# File 'lib/drb/drb.rb', line 1287

def self.default_safe_level(level)
  @@safe_level = level
end

.make_config(hash = {}) ⇒ Object

:nodoc:



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# File 'lib/drb/drb.rb', line 1303

def self.make_config(hash={})  # :nodoc:
  default_config = {
    :idconv => @@idconv,
    :verbose => @@verbose,
    :tcp_acl => @@acl,
    :load_limit => @@load_limit,
    :argc_limit => @@argc_limit,
    :safe_level => @@safe_level
  }
  default_config.update(hash)
end

.verbose ⇒ Object

Get the default value of the :verbose option.



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# File 'lib/drb/drb.rb', line 1299

def self.verbose
  @@verbose
end

.verbose=(on) ⇒ Object

Set the default value of the :verbose option.

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



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# File 'lib/drb/drb.rb', line 1294

def self.verbose=(on)
  @@verbose = on
end

Instance Method Details

#alive? ⇒ Boolean

Is this server alive?

Returns:

  • (Boolean) 


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# File 'lib/drb/drb.rb', line 1423

def alive?
  @thread.alive?
end

#check_insecure_method(obj, msg_id) ⇒ Object

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.

Raises:

  • (ArgumentError) 


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# File 'lib/drb/drb.rb', line 1500

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)
    desc = any_to_s(obj)
    raise NoMethodError, "private method `#{msg_id}' called for #{desc}"
  elsif obj.protected_methods.include?(msg_id)
    desc = any_to_s(obj)
    raise NoMethodError, "protected method `#{msg_id}' called for #{desc}"
  else
    true
  end
end

#here?(uri) ⇒ Boolean

Is uri the URI for this server?

Returns:

  • (Boolean) 


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# File 'lib/drb/drb.rb', line 1428

def here?(uri)
  @exported_uri.include?(uri)
end

#stop_service ⇒ Object

Stop this server.



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# File 'lib/drb/drb.rb', line 1433

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.join
  end
end

#to_id(obj) ⇒ Object

Convert a local object to a dRuby reference.



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# File 'lib/drb/drb.rb', line 1450

def to_id(obj)
  return nil if obj.__id__ == front.__id__
  @idconv.to_id(obj)
end

#to_obj(ref) ⇒ Object

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



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# File 'lib/drb/drb.rb', line 1443

def to_obj(ref)
  return front if ref.nil?
  return front[ref.to_s] if DRbURIOption === ref
  @idconv.to_obj(ref)
end

#verbose ⇒ Object

Get whether the server is in verbose mode.

In verbose mode, failed calls are logged to stdout.



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# File 'lib/drb/drb.rb', line 1420

def verbose; @config[:verbose]; end

#verbose=(v) ⇒ Object

Set whether to operate in verbose mode.

In verbose mode, failed calls are logged to stdout.



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# File 'lib/drb/drb.rb', line 1415

def verbose=(v); @config[:verbose]=v; end