Class: Bridge::TCPSocket

Inherits:
TCPSocket
  • Object
show all
Defined in:
lib/bridge/tcp_server.rb

Overview

This is the class returned by TCPServer.accept. It is a TCPSocket with a couple of extra features.

Defined Under Namespace

Classes: RetryError

Instance Method Summary collapse

Constructor Details

#initialize(cloud_host, cloud_port, listen_hosts, listen_keys) ⇒ TCPSocket

Returns a new instance of TCPSocket.



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# File 'lib/bridge/tcp_server.rb', line 14

def initialize(cloud_host, cloud_port, listen_hosts, listen_keys)
  @cloud_host = cloud_host
  @cloud_port = cloud_port
  @listen_hosts = listen_hosts
  @listen_keys = listen_keys
  
  super(@cloud_host, @cloud_port)
end

Instance Method Details

#send_bridge_request ⇒ Object 



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# File 'lib/bridge/tcp_server.rb', line 23

def send_bridge_request()
      write("BRIDGE / HTTP/1.1\r\n")
      write("Expect: 100-continue\r\n")
      @listen_hosts.each {|host|
write("Host: #{host}\r\n")
      }
      @listen_keys.each {|key|
write("Host-Key: #{key}\r\n")
      }
      write("\r\n")      
end

#setup ⇒ Object

This does the full setup process on the request, returning only when the connection is actually available.



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# File 'lib/bridge/tcp_server.rb', line 63

def setup()
    send_bridge_request
    code = nil
  name = nil
  headers = []
  while (line = gets())
    line = line.strip
    if (line == "")
      case code.to_i
      when 100 # 100 Continue, just a ping. Ignore.
        code = name = nil
        headers = []
        next
      when 101 # 101 Upgrade, successfuly got a connection.
        write("HTTP/1.1 100 Continue\r\n\r\n") # let the server know we're still here.
        return self
      when 401 # 401 Access Denied, key wasn't right.
        close()
        raise "HTTP BRIDGE error #{code}: host key was invalid or missing, but required."
      when 503, 504 # 503 Service Unavailable or 504 Gateway Timeout, just retry.
        close()
        sleep_time = headers.find {|header| header["Retry-After"] } || 5
        raise RetryError.new("BRIDGE server timed out or is overloaded, wait #{sleep_time}s to try again.", sleep_time)
      else
        raise "HTTP BRIDGE error #{code}: #{name} waiting for connection."
      end
    end

    if (!code && !name) # This is the initial response line
      if (match = line.match(%r{^HTTP/1\.[01] ([0-9]{3,3}) (.*)$}))
        code = match[1]
        name = match[2]
        next
      else
        raise "Parse error in BRIDGE request reply."
      end
    else
      if (match = line.match(%r{^(.+?):\s+(.+)$}))
        headers.push({match[1] => match[2]})
      else
        raise "Parse error in BRIDGE request reply's headers."
      end
    end
  end
  return nil
end

#verify ⇒ Object

This just tries to determine if the server will honor requests as specified above so that the TCPServer initializer can error out early if it won’t.



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# File 'lib/bridge/tcp_server.rb', line 38

def verify()
  send_bridge_request()
  begin
    line = gets()
    match = line.match(%r{^HTTP/1\.[01] ([0-9]{3,3}) (.*)$})
    if (!match)
      raise "HTTP BRIDGE error: bridge server sent incorrect reply to bridge request."
    end
    case code = match[1].to_i
    when 100, 101
      return true
  when 401 # 401 Access Denied, key wasn't right.
    raise "HTTP BRIDGE error #{code}: host key was invalid or missing, but required."
  when 503, 504 # 503 Service Unavailable or 504 Gateway Timeout
    raise "HTTP BRIDGE error #{code}: could not verify server can handle requests because it's overloaded."
   else
     raise "HTTP BRIDGE error #{code}: #{match[2]} unknown error connecting to bridge server."
    end 
  ensure
    close() # once we do this, we just assume the connection is useless.
  end
end