Logging — CasperJS 1.1.0-DEV documentation

# Logging

CasperJS allows logging using the casper.log() method and these standard event levels:

- `debug`
- `info`
- `warning`
- `error`

Sample use:

    var casper = require('casper').create();
    casper.log('plop', 'debug');
    casper.log('plip', 'warning');

Now, there are two things to distinguish: log storage and log display; by default CasperJS won’t print the logs to the standard output. In order to do so, you must enable the `verbose` Casper option:

    var casper = require('casper').create({
        verbose: true
    });

Also, by default Casper is configured to filter logging which is under the `error` level; you can override this setting by configuring the `logLevel` option:

    var casper = require('casper').create({
        verbose: true,
        logLevel: 'debug'
    });

You can also dump a JSON log of your Casper suite just by rendering the contents of the `Casper.result.log` property:

    var casper = require('casper').create({
    // ...
    casper.run(function() {
        require('utils').dump(this.result.log);
        this.exit();
    });

Last, if you print log messages to the standard output using the `verbose` option, you’ll get some fancy colors:

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

This will give the following output:

image

Hint

CasperJS doesn’t write logs on the filesystem. You have to implement this by yourself if needed.