mdns-js

mDNS-js

Pure JavaScript/NodeJS mDNS discovery implementation. It's definitely not a full implementation at the current state and it will NOT work in the browser.

The starting inspiration came from https://github.com/GoogleChrome/chrome-app-samples/tree/master/mdns-browser but adapted for node. It's not much left of that now though.

Install by

npm install mdns-js

Future

It would be great to have a full implementation of mDSN + DNS-SD in pure JS but progress will be slow unless someone is willing to pitch in with pull requests, specifications for wanted functions etc. Also, as you should avoid to have multiple mDNS stacks on a system this might clash with stuff like avahi and bonjour.

example

var mdns = require('mdns-js');
//if you have another mdns daemon running, like avahi or bonjour, uncomment following line
//mdns.excludeInterface('0.0.0.0');

var browser = mdns.createBrowser();

browser.on('ready', function () {
    browser.discover(); 
});

browser.on('update', function (data) {
    console.log('data:', data);
});

Debugging

This library is using the debug module from TJ Holowaychuk and can be used like this.

DEBUG=mdns:* node examples/simple.js

This will spit out LOTS of information that might be useful. If you have some issues with something where you might want to communicate the contents of a packet (ie create an issue on github) you could limit the debug information to just that.

DEBUG=mdns:browser:packet node examples/simple.js

Contributing

Pull-request will be gladly accepted.

If possible any api should be as close match to the api of node-mdns but be pragmatic. Look at issue #5.

Please run any existing tests with

npm test

and preferably add more tests.

Before creating a pull-request please run

npm run lint 

This will run jshint as well as jscs that will do some basic syntax and code style checks. Fix any issues befor committing and creating a pull-request.

Look at the .jshintrc and .jscs.json for the details.

License

Apache 2.0. See LICENSE file.

References

• https://github.com/GoogleChrome/chrome-app-samples/tree/master/samples/mdns-browser
• http://en.wikipedia.org/wiki/Multicast_DNS
• http://en.wikipedia.org/wiki/Zero_configuration_networking#Service_discovery
• RFC 6762 - mDNS - http://tools.ietf.org/html/rfc6762
• RFC 6763 - DNS Based Service Discovery (DNS-SD) - http://tools.ietf.org/html/rfc6763
• http://www.tcpipguide.com/free/t_DNSMessageHeaderandQuestionSectionFormat.htm

Contributors

• James Sigurðarson, @jamiees2
• Stefan Sauer, @ensonic