context is lost on 'end' event of http request stream

Here is a sample snippet:

const http = require('http');
var createNamespace = require('cls-hooked').createNamespace;
var session = createNamespace('session-ns');


const server = http.createServer(function (request, response) {
    session.run(function (ctx) {
        session.set('key', 1)
        read(request, response, function (req, res) {
            process._rawDebug(`DONE - key: ${session.get('key')}`)
            res.end(`key: ${session.get('key')}\r\n`)
        })
    })
})

server.listen(8080)

function read(req, res, done) {
    let body = [];
    req
        .on('data', function (chunk) {
            body.push(chunk)
        })
        .on('end', function () {
            body = Buffer.concat(body).toString()
            process._rawDebug(`End - key: ${session.get('key')}`)
            done(req, res)
        });
}

As you can see I have created a http server and read the body by a stream. run the snippet then use curl. curl http://localhost:8080
console output:

End - key: 1  
DONE - key: 1

for simple GET requests the context is correct, but when you send data in the body the context is lost. curl http://localhost:8080 -X POST -d aaaaaaaaaa console output:

End - key: undefined   
DONE - key: undefined

This issues is also related to this skonves/express-http-context#4. The problem is not the body-parser package, I have tracked it down and found that it is caused by the same issue as here, the callback of ‘end’ event looses context.

Node runtime: reproducible on all v8.14.0, v10.4.0, v10.3.0, and v10.14.1
OS: Ubuntu 18.04
cls-hooked: 4.2.2

[kjavaherpour]

Hi @Jeff-Lewis, any progress on this?

[Aidiiin]

@Strate @PoslavskySV I decided to use my own naive implementation.

const asyncHooks = require('async_hooks')

let contexts = {}

asyncHooks.createHook({
  init (asyncId, type, triggerAsyncId, resource) {
    if (contexts[triggerAsyncId] !== undefined) {
      contexts[asyncId] = contexts[triggerAsyncId]
    } else {
      contexts[asyncId] = {}
    }
  },

  destroy (asyncId) {
    delete contexts[asyncId]
  }
}).enable()


function run (callback) {
  let eid = asyncHooks.executionAsyncId()
  contexts[eid] = {}
  callback()
}

function set (k, v) {
  let eid = asyncHooks.executionAsyncId()
  let ctx = contexts[eid]
  if (ctx !== undefined) {
    ctx[k] = v
  }
}

function get (k) {
  let eid = asyncHooks.executionAsyncId()
  let ctx = contexts[eid]
  return ctx !== undefined ? ctx[k] : undefined
}

module.exports = {get, set, run, contexts}

It doesn’t have the above issue, and I use it with async/await on node 8.14 without any problems. Also, I use these packages on my project: express, body-parse, Sequelize, oauth2-server, cookie-parser, and request-promise-native. Though I had some issues with nested Promises at first but when I rewrote them with async/await it worked fine.