Node http2 - cannot read this.socket.readable

[PiniH]

Testing node's new http2 native module I couldn't get express to serve requests over http2,
Using node master build with --expose-http2 flag:

const express = require('express');

const app = express();

app.get('/express', (req, res) => {
  res.send('Hello from express');
});

const server = http2.createSecureServer({
  key,
  cert
}, app);

When requesting /express the server crashed with the following error:

(node:80731) ExperimentalWarning: The http2 module is an experimental API.
_http_incoming.js:104
  if (this.socket.readable)
                 ^

TypeError: Cannot read property 'readable' of undefined
    at IncomingMessage._read (_http_incoming.js:104:18)
    at IncomingMessage.Readable.read (_stream_readable.js:431:10)
    at IncomingMessage.read (_http_incoming.js:96:15)
    at resume_ (_stream_readable.js:811:12)
    at _combinedTickCallback (internal/process/next_tick.js:138:11)
    at process._tickCallback (internal/process/next_tick.js:180:9)

[dougwilson]

Hi @PiniH since it's experimental and just landed on master, I don't think we have done any research into what would need to be done to support it (either in Express.js or maybe bugs in Node.js experimental code). If you would like to help us and take on that task, that would be amazing :) !

[PiniH]

I would love to help investigate and assist with all the investigation/integration between the new http2 and express, however I would need guidance on how/where to start.
@jasnell

[dougwilson]

Yea, I'd need some time to take a look at what is going on to get some pointers for where to start.

[PiniH]

@dougwilson From quick investigation - the first problem starts in the init function, it sets the wrong prototype - it's Http2Request/Response all the way until

    setPrototypeOf(req, app.request)
    setPrototypeOf(res, app.response)

Not sure how to proceed now :)

[dougwilson]

Ah, the prototype. I guess that is different in the http2? Hmm, that sucks, because it is likely to be a large task to fix that. I would have assumed it wouldn't have been different, seeing as even the spdy module used those prototypes... and it's a third-party module that implemented http2 for a long time.

[PiniH]

Aye, it's a different constructor, I just started playing with it today, I will look into it more tomorrow and post my findings.

[PiniH]

I played with it some more, exposing Http2ServerRequest and Http2ServerResponse from node internal http2 files, and used them in the request/response files, (also had to define an empty setter for response.statusMessage - as Http2ServerResponse only defines a getter but no setter).

I managed to get a response (404, but still a response ;) ) - it seems to fail at matching the route -

 express:router dispatching GET /express +38s
  express:router query  : /express +1m
  express:router expressInit  : /express +34s

it seems to fail at a stack error (but only on the third call - not sure what's up with that yet) on

// get pathname of request
    var path = getPathname(req);

It got the correct path 2 times and then got stackoverflow. Any idea where/how to proceed?

[benjamingr]

What's path returned as, and what's getPathname doing?

[PiniH]

From what I'm seeing, the getPathname is working properly, until the layer that's called expressInit is running (I guess that's an internal layer?), and then the getPathname fails with stackoverflow, will update soon with more details.

[PiniH]

Amusing...

Http2ServerRequest defines getter for 'url' property as return this.path, express request.js defines 'path' as

return parse(this).pathname;

which calls - you guessed it, request.url :) resulting in stack overflow, when commenting out the 'path' getter in request.js I got a response.

[hansanghoon]

any progress so far? is there workaround without touching http2(or express) core?