Wagtail provides a comprehensive and extensible search interface. In addition, it provides ways to promote search results through "Editor's Picks." Wagtail also collects simple statistics on queries made through the search interface.
Wagtail provides a default frontend search interface which indexes the ``title`` field common to all ``Page``-derived models. Let's take a look at all the components of the search interface.
The most basic search functionality just needs a search box which submits a request. Since this will be reused throughout the site, let's put it in ``mysite/includes/search_box.html`` and then use ``{% include ... %}`` to weave it into templates:
The form is submitted to the url of the ``wagtailsearch_search`` view, with the search terms variable ``q``. The view will use its own basic search results template.
A collection of Page objects matching the query. The ``specific`` property of ``Page`` will give the most-specific subclassed model object for the Wagtail page. For instance, if an ``Event`` model derived from the basic Wagtail ``Page`` were included in the search results, you could use ``specific`` to access the custom properties of the ``Event`` model (``result.specific.date_of_event``).
A Wagtail ``Query`` object matching the terms. The ``Query`` model provides several class methods for viewing the statistics of all queries, but exposes only one property for single objects, ``query.hits``, which tracks the number of time the search string has been used over the lifetime of the site. ``Query`` also joins to the Editor's Picks functionality though ``query.editors_picks``. See :ref:`editors-picks`.
Editor's Picks are a way of explicitly linking relevant content to search terms, so results pages can contain curated content instead of being at the mercy of the search algorithm. In a template using the search results view, editor's picks can be accessed through the variable ``query.editors_picks``. To include editor's picks in your search results template, use the following properties.
``query.editors_picks.all``
This gathers all of the editor's picks objects relating to the current query, in order according to their sort order in the Wagtail admin. You can then iterate through them using a ``{% for ... %}`` loop. Each editor's pick object provides these properties:
Wagtail provides JSON search results when queries are made to the ``wagtailsearch_suggest`` view. To take advantage of it, we need a way to make that URL available to a static script. Instead of hard-coding it, let's set a global variable in our ``base.html``:
What if you wanted access to the rest of the results context or didn't feel like using JSON? Wagtail also provides a generalized AJAX interface where you can use your own template to serve results asynchronously.
The AJAX interface uses the same view as the normal HTML search, ``wagtailsearch_search``, but will serve different results if Django classifies the request as AJAX (``request.is_ajax()``). Another entry in your project settings will let you override the template used to serve this response:
In this template, you'll have access to the same context variables provided to the HTML template. You could provide a template in JSON format with extra properties, such as ``query.hits`` and editor's picks, or render an HTML snippet that can go directly into your results ``<div>``. If you need more flexibility, such as multiple formats/templates based on differing requests, you can set up a custom search view.
This functionality is still under active development to provide a streamlined interface, but take a look at ``wagtail/wagtail/wagtailsearch/views/frontend.py`` if you are interested in coding custom search views.
Other than ``BACKEND`` the keys are optional and default to the values shown. ``FORCE_NEW`` is used by elasticsearch-py. In addition, any other keys are passed directly to the Elasticsearch constructor as case-sensitive keyword arguments (e.g. ``'max_retries': 1``).
If you prefer not to run an Elasticsearch server in development or production, there are many hosted services available, including `Searchly`_, who offer a free account suitable for testing and development. To use Searchly:
Wagtail search backends implement the interface defined in ``wagtail/wagtail/wagtailsearch/backends/base.py``. At a minimum, the backend's ``search()`` method must return a collection of objects or ``model.objects.none()``. For a fully-featured search backend, examine the Elasticsearch backend code in ``elasticsearch.py``.
