GSoC week #5

Posted by Gábor Molnár on July 19, 2013

This is the summary of the fifth week of my Google Summer of Code project: HTTP/2 prototype server implementation in node.js.

This week was about achieving an important milestone: making the first successful HTTP/2 request with node-http2! I am quite happy that I managed to achieve it before going to holiday next week. Please note that it does not mean support for the HTTP/1 upgrade process or ALPN negotiation. It's raw HTTP/2 without any negotiation.

Before showing a quick demo, a little bit more info about other things I did this week. First of all, it is now possible to measure test coverage of the node-http2 codebase. It is made possible by a great code coverage tool called istanbul. It is this easy:

$ npm test --coverage


=============================== Coverage summary ===============================
Statements   : 91.18% ( 775/850 )
Branches     : 84.69% ( 249/294 )
Functions    : 88.03% ( 103/117 )
Lines        : 91.18% ( 775/850 )

It also generates a detailed, line-by-line analysis, that you can have a look at here. Using this, I managed to achieve 100% test coverage for the compression code, and in the process, I fixed several bugs that were discovered while writing the new test cases. I know that this does not mean that the compression code is now free of bugs, but still, it's more reliable than before.

To make a HTTP/2 request for yourself using node-http2, follow these steps.

Clone node-http2 and install the development dependencies.

$ git clone

$ cd node-http2

$ npm install

Start the server in one shell (use the HTTP2_PORT environment variable to change the port):

$ node ./example/server.js
Listening on localhost:8080, serving up files from ./example

Finally, use the client in an other shell to download the source code of the server:

$ node ./example/client.js 'http://localhost:8080/server.js' 2>/tmp/server.js

To see the nice colored log output, try these (or use bunyan --no-color if your terminal does not play nice with bunyan):

$ sudo npm install -g bunyan # To be able to use the bunyan command line tool to format the logs
$ HTTP2_LOG=debug node ./example/server.js | bunyan -o short
$ HTTP2_LOG=debug node ./example/client.js 'http://localhost:8080/server.js' 2>/tmp/server.js | bunyan -o short

The week after I come back, the plan is to implement a public API, sort out the handling of PUSH_PROMISE, and to write more documentation and test cases. I also plan to run a public server with publicly available debug logs to make it easy for client implementors to test with node-http2.

As usual, the latest code is published on npm (just type npm install http2 to install it), and the hosted version of the docs was updated as well. Feel free to open issues in the issue tracker or just email me directly if you find any problem.