http2.js

http2.js

An HTTP/2 (RFC 7540) pure JavaScript client and server implementation for node.js.

Original Source and Fork intent

This NodeJS http2.js module version is a fork of node-http2 hosted on Github originally made by Gábor Molnár and available here: https://github.com/molnarg/node-http2

This fork of node-http2 module named http2.js starts at version 4.0.0 in case previous the repository decides to pick up work again on version 3.x.x.

We are aware that node 8.4.0 now has experimental http2 support via --expose-http2, and we will continue to support the full JavaScript implementation of http2.js at our discretion until HTTP/2 is more fully supported in a broad range of client platforms.

Installation

npm install http2.js

API

The API is very similar to the standard node.js HTTPS API. The goal is perfect API compatibility, with additional HTTP2 related extensions (like server push).

Detailed API documentation is primarily maintained in the lib/http.js file and is available in the wiki as well.

Examples

Using as a server

var options = {
  key: fs.readFileSync('./example/localhost.key'),
  cert: fs.readFileSync('./example/localhost.crt')
};

require('http2.js').createServer(options, function(request, response) {
  response.end('Hello world!');
}).listen(8080);

Using as a client

require('http2.js').get('https://localhost:8080/', function(response) {
  response.pipe(process.stdout);
});

Simple static file server

An simple static file server serving up content from its own directory is available in the example directory. Running the server:

$ node ./example/server.js

Simple command line client

An example client is also available. Downloading the server's own source code from the server:

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

Server push

For a server push example, see the source code of the example server and client.

Status

• ALPN is only supported in node.js >= 5.0
• Upgrade mechanism to start HTTP/2 over unencrypted channel is not implemented yet (issue #4)
• Other minor features found in this list are not implemented yet

Development

Development dependencies

There's a few library you will need to have installed to do anything described in the following sections. After installing/cloning node-http2, run npm install in its directory to install development dependencies.

Used libraries:

• mocha for tests
• chai for assertions
• istanbul for code coverage analysis
• docco for developer documentation
• bunyan for logging

For pretty printing logs, you will also need a global install of bunyan (npm install -g bunyan).

Developer documentation

The developer documentation is generated from the source code using docco and can be viewed online here. If you'd like to have an offline copy, just run npm run-script doc.

Running the tests

It's easy, just run npm test. The tests are written in BDD style, so they are a good starting point to understand the code.

Test coverage

To generate a code coverage report, run npm test --coverage (which runs very slowly, be patient). Code coverage summary as of version 4.0.2:

Statements   : 89.41% ( 2017/2256 )
Branches     : 79.33% ( 852/1074 )
Functions    : 89.47% ( 238/266 )
Lines        : 89.45% ( 2009/2246 )

There's a hosted version of the detailed (line-by-line) coverage report here.

Logging

Logging is turned off by default. You can turn it on by passing a bunyan logger as log option when creating a server or agent.

When using the example server or client, it's very easy to turn logging on: set the HTTP2_LOG environment variable to fatal, error, warn, info, debug or trace (the logging level). To log every single incoming and outgoing data chunk, use HTTP2_LOG_DATA=1 besides HTTP2_LOG=trace. Log output goes to the standard error output. If the standard error is redirected into a file, then the log output is in bunyan's JSON format for easier post-mortem analysis.

Running the example server and client with info level logging output:

$ HTTP2_LOG=info node ./example/server.js

$ HTTP2_LOG=info node ./example/client.js 'https://localhost:8080/server.js' >/dev/null

Contributors

The co-maintainer of the project is Nick Hurley.

Code contributions are always welcome! People who contributed to node-http2 and http2.js so far:

• Kaazing
• Nick Hurley
• Nick Hurley
• Mike Belshe
• Yoshihiro Iwanaga
• Igor Novikov
• James Willcox
• David Björklund
• Patrick McManus

Special thanks to Google for financing the development of this module as part of their Summer of Code program (project: HTTP/2 prototype server implementation), and Nick Hurley of Mozilla, my GSoC mentor, who helped with regular code review and technical advices.

License

The MIT License

Copyright (C) 2013 Gábor Molnár [e-mail]

Changelog

4.0.3 (2018-07-18)

• Update http.js to add support on request for retry-after header on 503|429|302 status code.

  [About 503] The server returns an HTTP error 503 when more users than are allowed by the server's request queue limit have sent requests to a single server or when the actions of the client have triggered throttling.

  Retry-After If a Retry-After header ([RFC2616]) is present in the response, the client SHOULD<6> retry the request after waiting the number of seconds indicated by the Retry-After header. Any such value represents an estimate of when the server is expected to be able to process the request.