Logging
CasperJS allows logging using the :ref:`casper.log() <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.logs
property:
var casper = require('casper').create({ // ... casper.run(function() { require('utils').dump(this.logs); 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:
Hint
CasperJS doesn't write logs on the filesystem. You have to implement this by yourself if needed.