Using the command line

CasperJS ships with a built-in command line parser on top of PhantomJS' one, located in the cli module; it exposes passed arguments as positional ones and named options

But no worries for manipulating the cli module parsing API, a Casper instance always contains a ready to use cli property, allowing easy access of all these parameters.

Let's consider this simple casper script:

var casper = require("casper").create();

casper.echo("Casper CLI passed args:");
require("utils").dump(casper.cli.args);

casper.echo("Casper CLI passed options:");
require("utils").dump(casper.cli.options);

casper.exit();

Execution results:

$ casperjs test.js arg1 arg2 arg3 --foo=bar --plop anotherarg
Casper CLI passed args: [
    "arg1",
    "arg2",
    "arg3",
    "anotherarg"
]
Casper CLI passed options: {
    "casper-path": "/Users/niko/Sites/casperjs",
    "cli": true,
    "foo": "bar",
    "plop": true
}

Getting, checking or dropping parameters:

var casper = require("casper").create();
casper.echo(casper.cli.has(0));
casper.echo(casper.cli.get(0));
casper.echo(casper.cli.has(3));
casper.echo(casper.cli.get(3));
casper.echo(casper.cli.has("foo"));
casper.echo(casper.cli.get("foo"));
casper.cli.drop("foo");
casper.echo(casper.cli.has("foo"));
casper.echo(casper.cli.get("foo"));
casper.exit();

Execution results:

$ casperjs test.js arg1 arg2 arg3 --foo=bar --plop anotherarg
true
arg1
true
anotherarg
true
bar
false
undefined

// removing default options passed by the Python executable
casper.cli.drop("cli");
casper.cli.drop("casper-path");

if (casper.cli.args.length === 0 && Object.keys(casper.cli.options).length === 0) {
    casper.echo("No arg nor option passed").exit();
}

casperjs native options

The casperjs command has three available options:

• --direct: to prints out log messages to the console
• --log-level=[debug|info|warning|error] to set the :ref:`logging level <logging>`
• --engine=[phantomjs|slimerjs] to select the browser engine you want to use. CasperJS supports PhantomJS (default) that runs Webkit, and SlimerJS that runs Gecko.

Example:

$ casperjs --verbose --log-level=debug myscript.js

Last but not least, you can still use all PhantomJS standard CLI options as you would do with any other phantomjs script:

$ casperjs --web-security=no --cookies-file=/tmp/mycookies.txt myscript.js

Raw parameter values

By default, the cli object will process every passed argument & cast them to the appropriate detected type; example script:

var casper = require('casper').create();
var utils = require('utils');

utils.dump(casper.cli.get('foo'));

casper.exit();

If you run this script:

$ casperjs c.js --foo=01234567
1234567

As you can see, the 01234567 value has been cast to a Number.

Sometimes, you just want the original string; then you can use the raw property of the cli object, which contains the raw values passed parameters:

var casper = require('casper').create();
var utils = require('utils');

utils.dump(casper.cli.get('foo'));
utils.dump(casper.cli.raw.get('foo'));

casper.exit();

Sample usage:

$ casperjs c.js --foo=01234567
1234567
"01234567"