Class: Thin::Backends::Base

Inherits:
Object
  • Object
show all
Defined in:
lib/thin/backends/base.rb

Overview

A Backend connects the server to the client. It handles:

  • connection/disconnection to the server

  • initialization of the connections

  • monitoring of the active connections.

Implementing your own backend

You can create your own minimal backend by inheriting this class and defining the connect and disconnect method. If your backend is not based on EventMachine you also need to redefine the start, stop, stop! and config methods.

Direct Known Subclasses

SwiftiplyClient, TcpServer, UnixServer

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Base

Returns a new instance of Base.



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# File 'lib/thin/backends/base.rb', line 47

def initialize
  @connections                    = {}
  @timeout                        = Server::DEFAULT_TIMEOUT
  @persistent_connection_count    = 0
  @maximum_connections            = Server::DEFAULT_MAXIMUM_CONNECTIONS
  @maximum_persistent_connections = Server::DEFAULT_MAXIMUM_PERSISTENT_CONNECTIONS
  @no_epoll                       = false
  @ssl                            = nil
  @threaded                       = nil
  @started_reactor                = false
end

Instance Attribute Details

#maximum_connections ⇒ Object

Maximum number of file or socket descriptors that the server may open.



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# File 'lib/thin/backends/base.rb', line 21

def maximum_connections
  @maximum_connections
end

#maximum_persistent_connections ⇒ Object

Maximum number of connections that can be persistent



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# File 'lib/thin/backends/base.rb', line 24

def maximum_persistent_connections
  @maximum_persistent_connections
end

#no_epoll ⇒ Object

Disable the use of epoll under Linux



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# File 'lib/thin/backends/base.rb', line 45

def no_epoll
  @no_epoll
end

#persistent_connection_count ⇒ Object

Number of persistent connections currently opened



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# File 'lib/thin/backends/base.rb', line 42

def persistent_connection_count
  @persistent_connection_count
end

#server ⇒ Object

Server serving the connections throught the backend



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# File 'lib/thin/backends/base.rb', line 15

def server
  @server
end

#ssl=(value) ⇒ Object (writeonly)

Allow using SSL in the backend.



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# File 'lib/thin/backends/base.rb', line 38

def ssl=(value)
  @ssl = value
end

#ssl_options=(value) ⇒ Object (writeonly)

Allow using SSL in the backend.



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# File 'lib/thin/backends/base.rb', line 38

def ssl_options=(value)
  @ssl_options = value
end

#threaded=(value) ⇒ Object (writeonly)

Allow using threads in the backend.



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# File 'lib/thin/backends/base.rb', line 34

def threaded=(value)
  @threaded = value
end

#threadpool_size ⇒ Object

allows setting of the eventmachine threadpool size



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# File 'lib/thin/backends/base.rb', line 27

def threadpool_size
  @threadpool_size
end

#timeout ⇒ Object

Maximum time for incoming data to arrive



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# File 'lib/thin/backends/base.rb', line 18

def timeout
  @timeout
end

Instance Method Details

#close ⇒ Object

Free up resources used by the backend.



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# File 'lib/thin/backends/base.rb', line 112

def close
end

#config ⇒ Object

Configure the backend. This method will be called before droping superuser privileges, so you can do crazy stuff that require godlike powers here.



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# File 'lib/thin/backends/base.rb', line 101

def config
  # See http://rubyeventmachine.com/pub/rdoc/files/EPOLL.html
  EventMachine.epoll unless @no_epoll
  
  # Set the maximum number of socket descriptors that the server may open.
  # The process needs to have required privilege to set it higher the 1024 on
  # some systems.
  @maximum_connections = EventMachine.set_descriptor_table_size(@maximum_connections) unless Thin.win?
end

#connection_finished(connection) ⇒ Object

Called by a connection when it’s unbinded.



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# File 'lib/thin/backends/base.rb', line 125

def connection_finished(connection)
  @persistent_connection_count -= 1 if connection.can_persist?
  @connections.delete(connection.__id__)
  
  # Finalize gracefull stop if there's no more active connection.
  stop! if @stopping && @connections.empty?
end

#empty? ⇒ Boolean

Returns true if no active connection.

Returns:

  • (Boolean) 


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# File 'lib/thin/backends/base.rb', line 134

def empty?
  @connections.empty?
end

#running? ⇒ Boolean

Returns true if the backend is connected and running.

Returns:

  • (Boolean) 


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# File 'lib/thin/backends/base.rb', line 116

def running?
  @running
end

#size ⇒ Object

Number of active connections.



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# File 'lib/thin/backends/base.rb', line 139

def size
  @connections.size
end

#ssl? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/thin/backends/base.rb', line 39

def ssl?; @ssl end

#start ⇒ Object

Start the backend and connect it.



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# File 'lib/thin/backends/base.rb', line 60

def start
  @stopping = false
  starter   = proc do
    connect
    yield if block_given?
    @running = true
  end
  
  # Allow for early run up of eventmachine.
  if EventMachine.reactor_running?
    starter.call
  else
    @started_reactor = true
    EventMachine.run(&starter)
  end
end

#started_reactor? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/thin/backends/base.rb', line 120

def started_reactor?
  @started_reactor
end

#stop ⇒ Object

Stop of the backend from accepting new connections.



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# File 'lib/thin/backends/base.rb', line 78

def stop
  @running  = false
  @stopping = true
  
  # Do not accept anymore connection
  disconnect
  # Close idle persistent connections
  @connections.each_value { |connection| connection.close_connection if connection.idle? }
  stop! if @connections.empty?
end

#stop! ⇒ Object

Force stop of the backend NOW, too bad for the current connections.



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# File 'lib/thin/backends/base.rb', line 90

def stop!
  @running  = false
  @stopping = false
  
  EventMachine.stop if @started_reactor && EventMachine.reactor_running?
  @connections.each_value { |connection| connection.close_connection }
  close
end

#threaded? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/thin/backends/base.rb', line 35

def threaded?; @threaded end