pagination helpers

apps/amo/__init__.py

@@ -1,5 +1,36 @@
 """
 Miscellaneous helpers that make Django compatible with AMO.
 """
+import functools
+
+from django.core import paginator
 
 from .models import LegacyModel, TranslatedField
+
+
+def paginate(request, queryset, per_page=20):
+    """Get a Paginator, abstracting some common paging actions."""
+    p = paginator.Paginator(queryset, per_page)
+
+    # Get the page from the request, make sure it's an int.
+    try:
+        page = int(request.GET.get('page', 1))
+    except ValueError:
+        page = 1
+
+    # Get a page of results, or the first page if there's a problem.
+    try:
+        paginated = p.page(page)
+    except (paginator.EmptyPage, paginator.InvalidPage):
+        paginated = p.page(1)
+
+    paginated.add_query = functools.partial(add_query, request)
+    return paginated
+
+
+def add_query(request, **kwargs):
+    """Return absolute url to current page with ``kwargs`` added to GET."""
+    base = request.build_absolute_uri(request.path)
+    query = dict(request.GET)
+    query.update(kwargs)
+    return '%s?%s' % (base, '&'.join('%s=%s' % q for q in query.items()))

apps/amo/templates/amo/paginator.html

@@ -0,0 +1,20 @@
+{% if num_pages > 1 %}
+  <ol class="pagination">
+    {% for x in range(1, num_pages) %}
+    <li {{ x|class_selected(pager.number) }}>
+      <a href="{{ pager.add_query(page=x) }}">{{ x }}</a>
+    </li>
+    {% endfor %}
+    <li rel="next">
+      <a href="#page={{ pager.next_page_number() }}">
+        {{ pager.next_page_number() }}
+      </a>
+    </li>
+  </ol>
+  <div class="num-results">
+    {% trans begin=pager.start_index(), end=pager.end_index() %}
+      Results <strong>{{ begin }}</strong>&ndash;<strong>{{ end }}</strong>
+      of {{ count }}
+    {% endtrans %}
+  </div>
+{% endif %}

apps/amo/templatetags/__init__.py

@@ -0,0 +1,11 @@
+import jinja2
+
+from jingo import register, env
+
+
+@register.filter
+def paginator(pager):
+    c = {'pager': pager, 'num_pages': pager.paginator.num_pages,
+         'count': pager.paginator.count}
+    t = env.get_template('amo/paginator.html').render(**c)
+    return jinja2.Markup(t)