Kotti 0.1a4

A friendly, light-weight web content management system (WCMS). Written in Python, based on Pyramid and SQLAlchemy.

What is Kotti?

Kotti is a user-friendly web content management system (WCMS).

Features:

• Support for pluggable authentication modules and single sign-on

• Access control lists (ACL) for fine-grained security

• Separation between public area and editor interface

• Separation of basic and advanced functionality in the editor user interface, enabling a pleasant learning curve for editors

• Easily extensible with your own look & feel with no programming required

• Easily extensible with your own content types and views

Note

At this point, Kotti is experimental. You’re encouraged to try it out and give us feedback, but don’t use it in production yet. We’re likely to make fundamental changes to both Kotti’s API and its database structure in weeks to come.

Issue tracker and development

Kotti is developed on Github. The issue tracker also lives there.

Kotti’s mailing list for both users and developers is at http://groups.google.com/group/kotti

You can also find us on IRC: join the #kotti channel on irc.freenode.net.

Installation using virtualenv

It’s recommended to install Kotti inside a virtualenv.

Change into the directory of your Kotti download and issue:

$ python setup.py install

To run Kotti with the included development profile then type:

$ paster serve development.ini

To run all tests:

$ python setup.py nosetests

Installation using buildout

Alternatively, you can use the provided buildout configuration like so:

$ python bootstrap.py
$ bin/buildout

To run Kotti with the included development profile then type:

$ bin/paster serve development.ini

To run all tests:

$ bin/test

Configuring Kotti

Kotti includes two Paste Deploy configuration files in production.ini and development.ini.

kotti.authentication_policy_factory and kotti.authorization_policy_factory

You can override the authentication and authorization policy that Kotti uses. By default, Kotti uses these factories:

kotti.authentication_policy_factory = kotti.authtkt_factory
kotti.authorization_policy_factory = kotti.acl_factory

These settings correspond to pyramid.authentication.AuthTktAuthenticationPolicy and pyramid.authorization.ACLAuthorizationPolicy being used.

kotti.secret

kotti.secret and kotti.secret2 (optional) are used as salts for various hashing functions. Also, kotti.secret is the password of the default admin user. (Which you should change immediately.)

An example:

kotti.secret = qwerty
kotti.secret2 = asdfgh

With these settings, to log in as admin, you would log in as admin with the password qwerty.

kotti.secret is used as a salt to the passwords in the default user database. Changing it will result in the user database’s passwords becoming invalid.

kotti.session_factory

The kotti.session_factory configuration variable allows the overriding of the default session factory, which is pyramid.session.UnencryptedCookieSessionFactoryConfig.

kotti.principals

Kotti comes with a default user database implementation in kotti.security.principals. You can use the kotti.principals configuration variable to override the implementation used. The default looks like this:

kotti.principals = kotti.security.principals

kotti.templates.master_view and kotti.templates.master_edit

The default configuration for these two variables is:

kotti.templates.master_view = kotti:templates/view/master.pt
kotti.templates.master_edit = kotti:templates/edit/master.pt

You may override these to provide your own master templates.

kotti.templates.base_css, kotti.templates.view_css, and kotti.templates.edit_css

These variables define the CSS files used by the default master templates. The defaults are:

kotti.templates.base_css = kotti:static/base.css
kotti.templates.view_css = kotti:static/view.css
kotti.templates.edit_css = kotti:static/edit.css

kotti.includes

The default configuration here is:

kotti.includes =
  kotti.events kotti.views.view kotti.views.edit kotti.views.login

These point to modules that contain an includeme function. An includeme function that registers an edit view for an Event resource might look like this:

def includeme(config):
    config.add_view(
        edit_event,
        context=Event,
        name='edit',
        permission='edit',
        )

Examples of views and their registrations are in Kotti itself. Take a look at kotti.views.view and kotti.views.edit. XXX Need example extension package.

kotti.available_types

The default configuration here is:

kotti.available_types = kotti.resources.Document

You may replace or add your own types with this variable. An example:

kotti.available_types =
    kotti.resources.Document
    mypackage.resources.Calendar
    mypackage.resources.Event

kotti.resources.Document is itself a class that’s suitable as an example of a Kotti content type implementation:

class Document(Node):
    type_info = Node.type_info.copy(
        name=u'Document',
        add_view=u'add_document',
        addable_to=[u'Document'],
        )

    def __init__(self, body=u"", mime_type='text/html', **kwargs):
        super(Document, self).__init__(**kwargs)
        self.body = body
        self.mime_type = mime_type

documents = Table('documents', metadata,
    Column('id', Integer, ForeignKey('nodes.id'), primary_key=True),
    Column('body', UnicodeText()),
    Column('mime_type', String(30)),
)
mapper(Document, documents, inherits=Node, polymorphic_identity='document')

Authentication and Authorization

Authentication in Kotti is pluggable.

Auhorization in Kotti is controlled through the use of inherited access control lists. By default, the root object has an ACL that looks like this:

('Allow', 'group:admins', ALL_PERMISSIONS)
('Allow', 'system.Authenticated', ('view',))
('Allow', 'group:editors', ('add', 'edit'))

Principals are assigned to groups through the __groups__ special variable on Nodes. Again, the default root object serves as an example. Its __groups__ variable is set to {'admin': ['group:admins']}. Thus, the admin principal becomes part of the group:admins group throughout the site.

You are advised not to alter the ACL through the __acl__ attribute directly. Instead, to give bob editing rights by using the kotti.security.set_groups API:

from kotti.security import set_groups
set_groups(bobsfolder, 'bob', ['group:editors'])

Kotti currently lacks a user interface for user management.

Under the hood

Kotti is written in Python and based on the two excellent libraries Pyramid and SQLAlchemy. Kotti tries to leverage these libraries as much as possible, thus:

• minimizing the amount of code written,

• and allowing users familiar with these libraries to feel right at home.

Kotti aims to use few abstractions, yet it aims to be somewhat extensible.

You can extend Kotti with new content types and views from your own Python packages. If all that you want is replace templates and stylesheets, then it’s sufficient to hook up plain old files in the configuration.

For storage, Kotti uses any relational database for which there is support in SQLAlchemy. There’s no storage abstraction apart from that.

Read this blog post for more implementation details.

Thanks

Kotti thanks the University of Coimbra for their involvement and support.

History

0.1a4

• Added login form.

  With the development profile in development.ini, log in with user ‘admin’ and password ‘qwerty’. User management and sharing tab is a TODO.

• Add a default user database implementation in kotti.security.Principals.

  Override with kotti.principals configuration setting.

• Add inheritbale, nested groups support.

  Groups are stored in Node.__groups__. The API is kotti.security.list_groups and kotti.security.set_groups.