Simple Pagination

A utility class, a pager method and a jinja2 macro for paging query results and generating page links. Can be used with Google App Engine (GAE).

The utility class is the PageLinks class found in the page_links.py file. The class's initialization method accepts the following parameters:

page:           The current page
total_items:    The total number of items
per_page:       The number of items per page
url_root:       The start of the URL assigned to each page.
page_field:     The name of the URL parameter to use for pages
page_range:     The number of pages to show (should be odd)

Example Usage (GAE specific)

Simply copy the page_links.py file into your GAE project root. In your project's base handler (base controller) class, create a pager method:

form page_links import PageLinks

class BaseHandler(webapp.RequestHandler):

    # ...other code...

    def pager(self, query, page, total_items, per_page, url_root, page_field='pg', page_range= 9):
        try:
            page = int(page)
        except ValueError:
            page = 1

        entities = query.fetch(per_page, (page - 1) * per_page)

        pagination_links = PageLinks(
            page,
            total_items,
            per_page,
            url_root,
            page_field,
            page_range
        )

        pagination_links = pagination_links.get_links()
        return entities, pagination_links

Then, in your handlers, you can use the pager method as follows:

class Recruiters(BaseHandler):
    per_page = 20

    def get(self):
        # ...other code...

        page = self.request.get('pg')
        query = company.recruiters

        recruiters, pagination_links = self.pager(
            query,
            page,
            query.count(),
            self.per_page,
            '/a/recruiters',
        )

You can also use the following Jinja2 macro in your templates:

{% macro pagelinks(pagination_links) %}
<div id="pagelinks">
{% for link in pagination_links %}
   {{ link }}
{% endfor %}
</div>
{% endmacro %}

You can see Simple Pagination in action on Aktuální nabídky práce. It's a simple job board built on Google App Engine.

Credits

The PageLinks class is an adapted version of a utility class from the he3-appengine-lib project (http://code.google.com/p/he3-appengine-lib/wiki/PageLinks)