phantom.injectJs('casper.js');
var casper = new phantom.Casper({
    verbose: true,
    logLevel: 'debug'
})
casper.log('this is a debug message', 'debug');
casper.log('and an informative one', 'info');
casper.log('and a warning', 'warning');
casper.log('and an error', 'error');
casper.exit();