René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"AsyncWrap: TCPWrap created before MakeCallback","articleBody":"When creating a TCP server, the TCP handles there holds the socket is created in C++ land. The socket handle is then send to the `onconnection` server handle event using MakeCallback.\n\ncode link: https://github.com/nodejs/node/blob/master/src/tcp_wrap.cc#L259L272\n\nBecause the socket handle is created before `MakeCallback`, the `async_hooks_init_function` for the socket handle is called before `async_hooks_before_function` for the server handle. This makes it impossible to trace back the origin of the socket handle.\n\ndprof dump: http://bl.ocks.org/AndreasMadsen/raw/da3adb776bdfcf30f97f/ - Notice the free hanging blue line, which has an origin from nowhere. \n\n_edit: the link is only tested in Chrome, so here is a picture_\n![skaermbillede 2015-09-22 kl 20 23 43](https://cloud.githubusercontent.com/assets/505333/10027543/e676bf24-6167-11e5-8d97-c8a5f52be057.png)\n\nThe visualization/test was done with the following code:\n\n``` javascript\n'use strict';\nrequire('../../dprof.js');\n\nconst net = require('net');\n\nconst server = net.createServer(function (socket) {\n  socket.end('hallo world');\n});\n\nserver.listen(0, 'localhost', function () {\n  const addr = server.address();\n  const socket = net.connect(addr.port, addr.host, function () {\n    socket.once('readable', function () {\n      socket.read();\n      socket.once('readable', server.close.bind(server));\n    });\n  });\n});\n```\n\nThis issue appears to be caused by https://github.com/nodejs/node/commit/7dde95a8bd. I agree that is is wired to call `async_hooks_before_function` in the `AsyncWrap` constructor, particularly in this case because it suggests that the creation of the `TCPWrap` object and `onconnection` happens in two different async turns.\n\nHowever I'm not sure what the proper fix would be.\n\n/cc @trevnorris \n","author":{"url":"https://github.com/AndreasMadsen","@type":"Person","name":"AndreasMadsen"},"datePublished":"2015-09-21T17:15:30.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":14},"url":"https://github.com/2986/node/issues/2986"}