sleepyhollow-node

Node.js binder for two-way communication with PhantomJS. An IPC library in two modules, used in conjunction with sleepyhollow-phantom, via stdin and stderr. No socket.io or server-page hacks required. Sleepyhollow supports sending and receiving any JSON serialzable data type.

usage

To send and receive messages from Node.js to PhantomJS, require and invoke sleepyhollow-node. This returns an EventEmitter instance, which allows you to implement your own message passing system. It supports both event names as well as

var sleepyhollow = require('sleepyhollow-node');
var drjekyll = sleepyhollow('./node_modules/sleepyhollow-phantom/examples/simple.js');

drjekyll.emit('render', "http://example.com/");
drjekyll.on('rendered', function() {
    console.log('a page was rendered');
    drjekyll.emit('end');
});

sleepyhollow([...options], path)

Arguments:

1. options: Array: optional advanced options to be passed to PhantomJS.
2. path: String: the path to your PhantomJS code to run (using sleepyhollow-phantom)

See the usage example for the corresponding PhantomJS code.

Example:

var drjekyll = sleepyhollow('--ignore-ssl-errors=true', 'myscript.js');

emit(event, [param])

Arguments:

1. event - String: name of the event
2. param - Mixed: optional, any JSON.stringify()-able value is supported

Returns: null

Example:

drjekyll.emit("fetch", url);

on(event, listener)

Arguments:

1. event - String: name of the event
2. listener - Function(Mixed): receives a optional JSON.stringify()-able value

Example:

drjekyll.on('payload', function(obj) {
    console.log(obj.prop);
})

errors

The error support in PhantomJS isn't the best. sleepyhollow provides one custom event to listen for errors in your script:

var sleepyhollow = require('sleepyhollow-node');
var drjekyll = sleepyhollow('some-phantom-script.js');
drjekyll.on('error', function(data) {
    console.log(data);
});

Anything that comes across stdout will be passed over to the error event handler, so if you console.log in your PhantomJS code, it will be sent to that handler.

exit

If the child phantomjs process exits, an exit event is emitted.

drjekyll.on('exit', function() {
    console.log("phantom exited");
    process.exit();
});

If your Node process is exiting, sleepyhollow sends a SIGINT to tear down the phantomjs side.

examples

See the examples folder, these can be run with node.

testing

$ npm test