Andy Gayton cablehead

Ben Bangert raised an excellent point about leaking abandoned coroutines in a recent talk:

https://docs.google.com/presentation/d/1LO_WI3N-3p2Wp9PDWyv5B6EGFZ8XTOTNJ7Hd40WOUHo/edit#slide=id.g70b0035b2_1_168

This gist demonstrates a design decision in Vanilla to attempt to help with this.

The sender, recver ends of pipes are only connected by weakref's which have callback's registered for when the corresponding end is garbage collected. When one end is blocked on a send or a recv, and the other end is abandoned without being closed explicitly the blocked coroutine will receive a vanilla.Abandoned exception. This will also result in a StopIteration exception if you are iterating over a recver.

	local d = require("levee").d
	local ring = d.HashRing()

	ring:put("foo", 3, 2)
	print(ring:get("foo"))

	ring:del("foo")

	ring:put("foo", 3, 2)
	print(ring:get("foo") == nil)

	local levee = require("levee")
	local _ = levee._

	local h = levee.Hub()

	local err, serve = h.tcp:listen(9000)

	for conn in serve do
	h:spawn(function()
	while true do

	local levee = require("levee")

	local h = levee.Hub()


	local connections = 0


	-- HTTP endpoint to see number of connections

	levee build -e '
	local levee = require("levee")

	h = levee.Hub()

	local err, serve = h.tcp:listen(8080)

	for conn in serve do
	local msg = "Hello World"
	conn:write("HTTP/1.1 200 OK\n")

	import time
	import functools

	from decorator import decorator

	import pytest

	from tornado import ioloop
	from tornado import gen

	$ levee run -e '
	local levee = require("levee")

	local h = levee.Hub()

	local serve = h.http:listen(8000)

	for conn in serve do
	h:spawn(function()
	local req = conn:recv()

	local sys = require("levee.sys")

	local r, w = sys.os.pipe()
	sys.os.write(w, s, #s)

	local r, w = sys.fd.pipe()
	sys.fd.write(w, s, #s)



	d.Buffer()

	d.Fifo() -- ??
	d.FIFO()

	d.Heap()

	d.Set()