Using the command line
CasperJS ships with a built-in command line parser on top of PhantomJS' parser, located in the cli module. It exposes passed arguments as positional ones and named options
A Casper instance always contains a ready-to-use cli property for easy access to these parameters, so you don't have to worry about manipulating the cli module parsing API.
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();
Note
Please note the two casper-path and cli options; these are passed to the casper script through the casperjs Python executable.
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
Hint
You may need to wrap an option containing a space with escaped double quotes in Windows. --foo=\"space bar\"
Hint
What if you want to check if any arg or option has been passed to your script? Here you go:
// 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 print 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.
Warning
The --direct option has been renamed to --verbose. Although --direct will still work, it is now considered deprecated.
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
Hint
To remember what the native PhantomJS cli options are available, run the phantomjs --help command.
SlimerJS supports almost same options as PhantomJS.
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.
If you want the original string, use the raw property of the cli object, which contains the raw values of the 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"