caveman 1.0

Programmatic use

Caveman has been designed to be usable from your own code, for example, as part of a larger validation process, or as part of unit tests in your web application.

Caveman’s work is done by the ManifestChecker class. You instantiate it with two helpers: a get_url function that fetches data from URLs, and a logger object that gets logged messages:

from caveman import ManifestChecker

def get_url(url): ...

logger = ...

man_checker = ManifestChecker(get_url=get_url, logger=logger)

Then call its check_manifest method with the URL of the HTML page:

man_checker.check_manifest(url)

No value is returned: the output has been logged to the logger object. See the docstrings in the source code for details.

from caveman import ManifestChecker

class TestManifest(django.test.TestCase):
    def setUp(self):
        self.checker = ManifestChecker(get_url=self.get_url, logger=self)
        self.caveman_log = []

    def get_url(self, url):
        """A get_url function for `caveman.ManifestChecker`."""
        # Use the Django test client to fetch the URL.
        response = self.client.get(url)
        return response.status_code, response.content, response

    # Record the serious Caveman messages in `self.caveman_log`.
    def debug(self, msg):       pass
    def info(self, msg):        pass
    def warning(self, msg):     self.caveman_log.append(msg)
    def error(self, msg):       self.caveman_log.append(msg)

    def test_my_manifest(self):
        """Caveman produces no warnings or errors for the cache manifest."""
        self.checker.check_manifest("/")
        self.assertEqual([], self.caveman_log)

Limitations

Caveman only pulls the HTML page you specify. Although it validates links to other HTML pages against the manifest, it does not pull those linked-to pages and verify their resources.

Certain rules from the HTML5 spec are not validated.

More information

Caveman can be downloaded from PyPI: http://pypi.python.org/pypi/caveman

The HTML5 cache manifest spec is at http://www.w3.org/TR/html5/offline.html

Docs at http://nedbatchelder.com/code/caveman.

Code repository and issue tracker are at bitbucket.org.