Class: DRb::DRbServer

Relationships & Source Files
Namespace Children
Classes: `InvokeMethod`
Inherits:	Object
Defined in:	lib/drb/drb.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 start_service.

Constant Summary

INSECURE_METHOD = Internal use only

List of insecure methods.

These methods are not callable via dRuby.

# File 'lib/drb/drb.rb', line 1597
```
[
  :__send__
]
```

Class Attribute Summary

.verbose rw Internal use only

Get the default value of the :verbose option.
.verbose=(on) rw Internal use only

Set the default value of the :verbose option.

Class Method Summary

.default_acl(acl) Internal use only

Set the default access control list to acl.
.default_argc_limit(argc) Internal use only

Set the default value for the :argc_limit option.
.default_id_conv(idconv) Internal use only

Set the default value for the :id_conv option.
.default_load_limit(sz) Internal use only

Set the default value for the :load_limit option.
.make_config(hash = {}) Internal use only
.new(uri = nil, front = nil, config_or_acl = nil) ⇒ DRbServer constructor Internal use only

Create a new DRbServer instance.

Instance Attribute Summary

#alive? ⇒ Boolean readonly Internal use only

Is this server alive?
#config readonly Internal use only

The configuration of this DRbServer.
#front readonly Internal use only

The front object of the DRbServer.
#thread readonly Internal use only

The main thread of this DRbServer.
#uri readonly Internal use only

The URI of this DRbServer.
#verbose rw Internal use only

Get whether the server is in verbose mode.
#verbose=(v) rw Internal use only

Set whether to operate in verbose mode.

Instance Method Summary

#error_print(exception)
#main_loop

The main loop performed by a DRbServer’s internal thread.
#check_insecure_method(obj, msg_id) Internal use only

Check that a method is callable via dRuby.
#here?(uri) ⇒ Boolean Internal use only

Is #uri the URI for this server?
#stop_service Internal use only

Stop this server.
#to_id(obj) Internal use only

Convert a local object to a dRuby reference.
#to_obj(ref) Internal use only

Convert a dRuby reference to the local object it refers to.
#any_to_s(obj) private Internal use only

Coerce an object to a string, providing our own representation if to_s is not defined for the object.
#insecure_method?(msg_id) ⇒ Boolean private Internal use only

Has a method been included in the list of insecure methods?
#run private Internal use only

Starts the ::DRb main loop in a new thread.
#shutdown private Internal use only

Constructor Details

.new(uri = nil, front = nil, config_or_acl = nil) ⇒ `DRbServer`

This method is for internal use only.

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.

[ GitHub ]

# File 'lib/drb/drb.rb', line 1479


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]

  @grp = ThreadGroup.new
  @thread = run

  DRb.regist_server(self)
end

Class Attribute Details

.verbose (rw)

This method is for internal use only.

Get the default value of the :verbose option.

[ GitHub ]

# File 'lib/drb/drb.rb', line 1422


def self.verbose
  @@verbose
end

.verbose=(on) (rw)

This method is for internal use only.

Set the default value of the :verbose option.

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

[ GitHub ]

# File 'lib/drb/drb.rb', line 1417


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

Class Method Details

.default_acl(acl)

This method is for internal use only.

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

.default_argc_limit(argc)

This method is for internal use only.

Set the default value for the :argc_limit option.

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

[ GitHub ]

# File 'lib/drb/drb.rb', line 1389


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

.default_id_conv(idconv)

This method is for internal use only.

Set the default value for the :id_conv option.

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

[ GitHub ]

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


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

.default_load_limit(sz)

This method is for internal use only.

Set the default value for the :load_limit option.

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

[ GitHub ]

# File 'lib/drb/drb.rb', line 1396


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

.make_config(hash = {})

This method is for internal use only.

[ GitHub ]

# File 'lib/drb/drb.rb', line 1426


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

Instance Attribute Details

#alive? ⇒ `Boolean` (readonly)

This method is for internal use only.

Is this server alive?

[ GitHub ]

# File 'lib/drb/drb.rb', line 1534


def alive?
  @thread.alive?
end

#config (readonly)

This method is for internal use only.

The configuration of this DRbServer

[ GitHub ]

# File 'lib/drb/drb.rb', line 1521


attr_reader :config

#front (readonly)

This method is for internal use only.

The front object of the DRbServer.

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

[ GitHub ]

# File 'lib/drb/drb.rb', line 1518


attr_reader :front

#thread (readonly)

This method is for internal use only.

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.

[ GitHub ]

# File 'lib/drb/drb.rb', line 1512


attr_reader :thread

#uri (readonly)

This method is for internal use only.

The URI of this DRbServer.

[ GitHub ]

# File 'lib/drb/drb.rb', line 1505


attr_reader :uri

#verbose (rw)

This method is for internal use only.

Get whether the server is in verbose mode.

In verbose mode, failed calls are logged to stdout.

[ GitHub ]

# File 'lib/drb/drb.rb', line 1531


def verbose; @config[:verbose]; end

#verbose=(v) (rw)

This method is for internal use only.

Set whether to operate in verbose mode.

In verbose mode, failed calls are logged to stdout.

[ GitHub ]

# File 'lib/drb/drb.rb', line 1526


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

Instance Method Details

#any_to_s(obj) (private)

This method is for internal use only.

Coerce an object to a string, providing our own representation if to_s is not defined for the object.

[ GitHub ]

# File 'lib/drb/drb.rb', line 1608


def any_to_s(obj)
  "#{obj}:#{obj.class}"
rescue
  Kernel.instance_method(:to_s).bind_call(obj)
end

#check_insecure_method(obj, msg_id)

This method is for internal use only.

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)

[ GitHub ]

# File 'lib/drb/drb.rb', line 1622


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)

  case obj
  when Object
    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
  else
    if Kernel.instance_method(:private_methods).bind(obj).call.include?(msg_id)
      desc = any_to_s(obj)
      raise NoMethodError, "private method '#{msg_id}' called for #{desc}"
    elsif Kernel.instance_method(:protected_methods).bind(obj).call.include?(msg_id)
      desc = any_to_s(obj)
      raise NoMethodError, "protected method '#{msg_id}' called for #{desc}"
    else
      true
    end
  end
end

#error_print(exception)

[ GitHub ]

# File 'lib/drb/drb.rb', line 1746


def error_print(exception)
  exception.backtrace.inject(true) do |first, x|
    if first
      $stderr.puts "#{x}: #{exception} (#{exception.class})"
    else
      $stderr.puts "\tfrom #{x}"
    end
    false
  end
end

#here?(uri) ⇒ `Boolean`

This method is for internal use only.

Is #uri the URI for this server?

[ GitHub ]

# File 'lib/drb/drb.rb', line 1539


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

#insecure_method?(msg_id) ⇒ `Boolean` (private)

This method is for internal use only.

Has a method been included in the list of insecure methods?

[ GitHub ]

# File 'lib/drb/drb.rb', line 1602


def insecure_method?(msg_id)
  INSECURE_METHOD.include?(msg_id)
end

#main_loop

The main loop performed by a DRbServer’s internal thread.

Accepts a connection from a client, and starts up its own thread to handle it. This thread loops, receiving requests from the client, invoking them on a local object, and returning responses, until the client closes the connection or a local method call fails.

[ GitHub ]

# File 'lib/drb/drb.rb', line 1764


def main_loop
  client0 = @protocol.accept
  return nil if !client0
  Thread.start(client0) do |client|
    @grp.add Thread.current
    Thread.current['DRb'] = { 'client' => client ,
                              'server' => self }
    DRb.mutex.synchronize do
      client_uri = client.uri
      @exported_uri << client_uri unless @exported_uri.include?(client_uri)
    end
    _last_invoke_method = nil
    loop do
      begin
        succ = false
        invoke_method = InvokeMethod.new(self, client)
        succ, result = invoke_method.perform
        error_print(result) if !succ && verbose
        unless DRbConnError === result && result.message == 'connection closed'
          client.send_reply(succ, result)
        end
      rescue Exception => e
        error_print(e) if verbose
      ensure
        _last_invoke_method = invoke_method
        client.close unless succ
        if Thread.current['DRb']['stop_service']
          shutdown
          break
        end
        break unless succ
      end
    end
  end
end

#run (private)

This method is for internal use only.

Starts the ::DRb main loop in a new thread.

[ GitHub ]

# File 'lib/drb/drb.rb', line 1583


def run
  Thread.start do
    begin
      while main_loop
      end
    ensure
      @protocol.close if @protocol
    end
  end
end

#shutdown (private)

This method is for internal use only.

[ GitHub ]

# File 'lib/drb/drb.rb', line 1568


def shutdown
  current = Thread.current
  if @protocol.respond_to? :shutdown
    @protocol.shutdown
  else
    [@thread, *@grp.list].each { |thread|
      thread.kill unless thread == current # xxx: Thread#kill
    }
  end
  @thread.join unless @thread == current
end

#stop_service

This method is for internal use only.

Stop this server.

[ GitHub ]

# File 'lib/drb/drb.rb', line 1544


def stop_service
  DRb.remove_server(self)
  if  Thread.current['DRb'] && Thread.current['DRb']['server'] == self
    Thread.current['DRb']['stop_service'] = true
  else
    shutdown
  end
end

#to_id(obj)

This method is for internal use only.

Convert a local object to a dRuby reference.

[ GitHub ]

# File 'lib/drb/drb.rb', line 1561


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

#to_obj(ref)

This method is for internal use only.

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

[ GitHub ]

# File 'lib/drb/drb.rb', line 1554


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

Class: DRb::DRbServer

Overview

Constant Summary

Class Attribute Summary

Class Method Summary

Instance Attribute Summary

Instance Method Summary

Constructor Details

.new(uri = nil, front = nil, config_or_acl = nil) ⇒ DRbServer

Class Attribute Details

.verbose (rw)

.verbose=(on) (rw)

Class Method Details

.default_acl(acl)

.default_argc_limit(argc)

.default_id_conv(idconv)

.default_load_limit(sz)

.make_config(hash = {})

Instance Attribute Details

#alive? ⇒ Boolean (readonly)

#config (readonly)

#front (readonly)

#thread (readonly)

#uri (readonly)

#verbose (rw)

#verbose=(v) (rw)

Instance Method Details

#any_to_s(obj) (private)

#check_insecure_method(obj, msg_id)

#error_print(exception)

#here?(uri) ⇒ Boolean

#insecure_method?(msg_id) ⇒ Boolean (private)

#main_loop

#run (private)

#shutdown (private)

#stop_service

#to_id(obj)

#to_obj(ref)

.new(uri = nil, front = nil, config_or_acl = nil) ⇒ `DRbServer`

#alive? ⇒ `Boolean` (readonly)

#here?(uri) ⇒ `Boolean`

#insecure_method?(msg_id) ⇒ `Boolean` (private)