Following is a quick overview of our wiki application, to help us understand the changes that we will be doing next in our default files generated by the zodb scafffold.
We choose to use reStructuredText markup in the wiki text. Translation from reStructuredText to HTML is provided by the widely used docutils Python module. We will add this module in the dependency list on the project setup.py file.
The root resource, named Wiki, will be a mapping of wiki page names to page resources. The page resources will be instances of a Page class and they store the text content.
URLs like /PageName will be traversed using Wiki[ PageName ] => page, and the context that results is the page resource of an existing page.
To add a page to the wiki, a new instance of the page resource is created and its name and reference are added to the Wiki mapping.
A page named FrontPage containing the text This is the front page, will be created when the storage is initialized, and will be used as the wiki home page.
There will be four views to handle the normal operations of viewing, editing and adding wiki pages. Two additional views will handle the login and logout tasks related to security.
We’ll eventually be adding security to our application. The components we’ll use to do this are below.
USERS, a dictionary mapping users names to their corresponding passwords.
GROUPS, a dictionary mapping user names to a list of groups they belong to.
groupfinder, an authorization callback that looks up USERS and GROUPS. It will be provided in a new security.py file.
An ACL is attached to the root resource. Each row below details an ACE:
Action |
Principal |
Permission |
---|---|---|
Allow |
Everyone |
View |
Allow |
group:editors |
Edit |
Permission declarations are added to the views to assert the security policies as each request is handled.
The URL, context, actions, template and permission associated to each view are listed in the following table:
URL | View | Context | Action | Template | Permission |
---|---|---|---|---|---|
/ | view_wiki | Wiki | Redirect to /FrontPage | ||
/PageName | view_page [1] | Page | Display existing page [2] | view.pt | view |
/PageName/edit_page | edit_page | Page | Display edit form with existing content. If the form was submitted, redirect to /PageName |
edit.pt | edit |
/add_page/PageName | add_page | Wiki | Create the page PageName in storage, display the edit form without content. If the form was submitted, redirect to /PageName |
edit.pt | edit |
/login | login | Wiki, Forbidden [3] | Display login form. If the form was submitted, authenticate.
|
login.pt | |
/logout | logout | Wiki | Redirect to /FrontPage |
[1] | This is the default view for a Page context when there is no view name. |
[2] | Pyramid will return a default 404 Not Found page if the page PageName does not exist yet. |
[3] | pyramid.exceptions.Forbidden is reached when a user tries to invoke a view that is not authorized by the authorization policy. |