Cool.io::TCPServer continues to receive data even if its close method is called
abicky opened this issue · comments
I expect Cool.io::TCPServer
to stop receiving data after Cool.io::TCPServer#close
is called, but it continues to receive data. Is this behavior expected?
Here is a reproducible code:
require 'socket'
require 'cool.io'
HOST = '127.0.0.1'
PORT = 1234
class ServerConnection < Coolio::TCPSocket
def on_read(data)
puts "received: #{data}"
end
end
event_loop = Coolio::Loop.new
server = Cool.io::TCPServer.new(HOST, PORT, ServerConnection)
server.attach(event_loop)
server_thr = Thread.new { event_loop.run }
sock = TCPSocket.new(HOST, PORT)
puts "cool.io version: #{Coolio::VERSION}"
puts 'send a message'
sock.send "message", 0
sleep 1
server.close
puts 'server stopped'
sleep 1
puts 'send a message'
sock.send "message", 0
sleep 1
puts 'done'
Output
% docker run --rm -v $PWD/coolio_example.rb:/coolio_example.rb ruby:2.4.2 bash -c 'gem install cool.io && ruby /coolio_example.rb'
Building native extensions. This could take a while...
Successfully installed cool.io-1.5.1
1 gem installed
cool.io version: 1.5.1
send a message
received: message
server stopped
send a message
received: message
done
You need to call Loop#stop
before server.close
.
I think this is expected behavior.
What Cool.io::TCPServer#close does is just closing a socket listening*, not closing the accepted socket. the method is similar to TcpServer#close
.
So here is the correct code to shutdown coolio.
require 'socket'
require 'cool.io'
HOST = '127.0.0.1'
PORT = 1234
class ServerConnection < Coolio::TCPSocket
def on_read(data)
puts "received: #{data}"
end
end
event_loop = Coolio::Loop.new
conns = []
server = Cool.io::TCPServer.new(HOST, PORT, ServerConnection) do |conn|
conns << conn
end
server.attach(event_loop)
server_thr = Thread.new { event_loop.run }
sock = TCPSocket.new(HOST, PORT)
puts "cool.io version: #{Coolio::VERSION}"
puts 'send a message'
sock.send "message", 0
sleep 1
server.close
conns.each do |c|
c.close
end
puts 'server stopped'
sleep 1
puts 'send a message'
sock.send "message", 0
sleep 1
puts 'done'
$ docker run --rm -v $PWD/coolio_example.rb:/coolio_example.rb ruby:2.6 bash -c 'gem install cool.io && ruby /coolio_example.rb'
Building native extensions. This could take a while...
Successfully installed cool.io-1.5.4
1 gem installed
cool.io version: 1.5.4
send a message
received: message
server stopped
send a message
done
We can find another problem here.
Calling second sock.send "message", 0
succeeded even if the accepted socket was already closed on the server-side.
it seems to be related to fluent/fluentd#1985 (also I don't think this is coolio's issue, it's a TCP stack issue).
It sounds wrong to me, but please consider making a PR, as I don't think anyone is invested in maintaining this code base.