var PDF = require('pdf-builder')
 
new PDF()
    .setGlobalOptions({
        headerFontSize:  18,
        headerSpacing:   10,
        marginTop:       30,
        debugJavascript: true
    })
    .addPath('http://google.com', {
        headerCenter: 'Google',
        runScript: function() {
            console.log('Google input being processed...')
        }
    })
    .addPath('http://wkhtmltopdf.com/', {
        headerCenter: 'wkhtmltopdf',
        fnInput: 'wkhtmltopdf input being processed...',
        runScript: function(foo) {
            console.log(foo) // wkhtmltopdf input being processed...
        }
    })
    .setCustomCommand(function() {
        // Inject custom logic into command construction
        return this.getCommand().replace(/wkhtmltopdf.com/g, 'wkhtmltopdf.org')
    })
    .writeFile('output.pdf', function(err, result) {
        // result contains any warnings / console output from input execution
        console.log(result)
        console.log('Done!')
 
        /*
            Output:
 
            :1 Google input being processed...
            :1 wkhtmltopdf input being processed...
            Done!
        */
    })