Modeladmin search backend

docs/reference/contrib/modeladmin/indexview.rst

@@ -287,10 +287,36 @@ Set ``search_fields`` to enable a search box at the top of the index page
 for your model. You should add names of any fields on the model that should
 be searched whenever somebody submits a search query using the search box.
 
-Searching is all handled via Django's QuerySet API, rather than using Wagtail's
-search backend. This means it will work for all models, whatever search backend
+Searching is handled via Django's QuerySet API by default,
+see `ModelAdmin.search_handler_class`_ about changing this behaviour.
+This means by default it will work for all models, whatever search backend
 your project is using, and without any additional setup or configuration.
 
+.. _modeladmin_search_handler_class:
+
+-----------------------------------
+``ModelAdmin.search_handler_class``
+-----------------------------------
+
+The default value for this property is the `DjangoORMSearchHandler`, which uses
+the Django ORM to perform `icontains` lookups on the fields specified by `search_fields`.
+
+If you would prefer to use the built-in Wagtail search backend to search your models,
+assuming they are indexed, you can override this property with the included
+`WagtailBackendSearchHandler` class e.g.
+
+.. code-block:: python
+    from wagtail.contrib.helpers import WagtailBackendSearchHandler
+    from .models import IndexedModel
+
+    class DemoAdmin(ModelAdmin):
+        model = IndexedModel
+        search_handler_class = WagtailBackendSearchHandler
+
+Note: when using the `WagtailBackendSearchHandler` the `search_fields` are used to limit
+the backend to search only over the specified fields, so those fields must be indexed
+by the backend.
+
 .. _modeladmin_ordering:
 
 ---------------------------
@@ -646,4 +672,3 @@ See the following part of the docs to find out more:
 
 See the following part of the docs to find out more:
 :ref:`modeladmin_overriding_views`
-

wagtail/contrib/modeladmin/helpers/__init__.py

@@ -1,3 +1,4 @@
-from .button import ButtonHelper, PageButtonHelper # NOQA
-from .permission import PagePermissionHelper, PermissionHelper # NOQA
-from .url import AdminURLHelper, PageAdminURLHelper # NOQA
+from .button import ButtonHelper, PageButtonHelper  # NOQA
+from .permission import PagePermissionHelper, PermissionHelper  # NOQA
+from .search import DjangoORMSearchHandler, WagtailBackendSearchHandler  # NOQA
+from .url import AdminURLHelper, PageAdminURLHelper  # NOQA

wagtail/contrib/modeladmin/helpers/search.py

@@ -0,0 +1,61 @@
+import operator
+from functools import reduce
+
+from django.contrib.admin.utils import lookup_needs_distinct
+from django.db.models import Q
+
+from wagtail.search.backends import get_search_backend
+
+
+class BaseSearchHandler:
+    def __init__(self, search_fields):
+        self.search_fields = search_fields
+
+    def search_queryset(self, queryset, search_term, **kwargs):
+        """
+        Returns a tuple containing a queryset to implement the search,
+        and a boolean indicating if the results may contain duplicates.
+        """
+        raise NotImplementedError()
+
+    @property
+    def show_search_form(self):
+        """
+        Returns a boolean that determines whether a search form should be
+        displayed in the IndexView UI
+        """
+        return True
+
+
+class DjangoORMSearchHandler(BaseSearchHandler):
+    def search_queryset(self, queryset, search_term):
+        if not search_term or not self.search_fields:
+            return queryset, False
+        use_distinct = False
+        orm_lookups = ['%s__icontains' % str(search_field)
+                       for search_field in self.search_fields]
+        for bit in search_term.split():
+            or_queries = [Q(**{orm_lookup: bit})
+                          for orm_lookup in orm_lookups]
+            queryset = queryset.filter(reduce(operator.or_, or_queries))
+        opts = queryset.model._meta
+        for search_spec in orm_lookups:
+            # Check wether out results may have duplicates, then remove them
+            if lookup_needs_distinct(opts, search_spec):
+                use_distinct = True
+                break
+        return queryset, use_distinct
+
+    @property
+    def show_search_form(self):
+        return bool(self.search_fields)
+
+
+class WagtailBackendSearchHandler(BaseSearchHandler):
+    def search_queryset(self, queryset, search_term, backend='default'):
+        if not search_term:
+            return queryset, False
+        backend = get_search_backend(backend)
+        if self.search_fields:
+            return backend.search(search_term, queryset, fields=self.search_fields), False
+        return backend.search(search_term, queryset), False

wagtail/contrib/modeladmin/options.py

@@ -12,8 +12,8 @@
 from wagtail.core.models import Page
 
 from .helpers import (
-    AdminURLHelper, ButtonHelper, PageAdminURLHelper, PageButtonHelper, PagePermissionHelper,
-    PermissionHelper)
+    AdminURLHelper, ButtonHelper, DjangoORMSearchHandler, PageAdminURLHelper, PageButtonHelper,
+    PagePermissionHelper, PermissionHelper)
 from .menus import GroupMenuItem, ModelAdminMenuItem, SubMenu
 from .mixins import ThumbnailMixin  # NOQA
 from .views import ChooseParentView, CreateView, DeleteView, EditView, IndexView, InspectView
@@ -96,6 +96,7 @@ class ModelAdmin(WagtailRegisterable):
     inspect_template_name = ''
     delete_template_name = ''
     choose_parent_template_name = ''
+    search_handler_class = DjangoORMSearchHandler
     permission_helper_class = None
     url_helper_class = None
     button_helper_class = None

wagtail/contrib/modeladmin/templates/modeladmin/includes/search_form.html

@@ -1,5 +1,5 @@
 {% load i18n static %}
-{% if view.search_fields %}
+{% if show_search %}
 <form id="changelist-search" class="col search-form" action="{{ view.index_url }}" method="get">
     <ul class="fields">
         <li class="required">

wagtail/contrib/modeladmin/tests/test_page_modeladmin.py

@@ -40,12 +40,12 @@ def test_filter(self):
             self.assertEqual(eventpage.audience, 'public')
 
     def test_search(self):
-        response = self.get(q='Someone')
+        response = self.get(q='moon')
 
         self.assertEqual(response.status_code, 200)
 
-        # There are two eventpage's where the title contains 'Someone'
-        self.assertEqual(response.context['result_count'], 1)
+        # There are two eventpage's where the location is 'The moon'
+        self.assertEqual(response.context['result_count'], 2)
 
     def test_ordering(self):
         response = self.get(o='0.1')

wagtail/contrib/modeladmin/tests/test_simple_modeladmin.py

@@ -6,9 +6,11 @@
 from django.test import TestCase
 
 from wagtail.admin.edit_handlers import FieldPanel, TabbedInterface
+from wagtail.contrib.modeladmin.helpers.search import DjangoORMSearchHandler
 from wagtail.images.models import Image
 from wagtail.images.tests.utils import get_test_image_file
 from wagtail.tests.modeladmintest.models import Author, Book, Publisher, Token
+from wagtail.tests.modeladmintest.wagtail_hooks import BookModelAdmin
 from wagtail.tests.utils import WagtailTestUtils
 
 
@@ -65,14 +67,28 @@ def test_filter(self):
         for book in response.context['object_list']:
             self.assertEqual(book.author_id, 1)
 
-    def test_search(self):
+    def test_search_indexed(self):
         response = self.get(q='of')
 
         self.assertEqual(response.status_code, 200)
 
         # There are two books where the title contains 'of'
         self.assertEqual(response.context['result_count'], 2)
 
+    def test_search_form_present(self):
+        # Test the backend search handler allows the search form to render
+        response = self.get()
+
+        self.assertContains(response, '<input id="id_q"')
+
+
+    def test_search_form_absent(self):
+        # DjangoORMSearchHandler + no search_fields, search form should be absent
+        with mock.patch.object(BookModelAdmin, 'search_handler_class', DjangoORMSearchHandler):
+            response = self.get()
+
+            self.assertNotContains(response, '<input id="id_q"')
+
     def test_ordering(self):
         response = self.get(o='0.1')
 
@@ -109,6 +125,13 @@ def setUp(self):
     def get(self, **params):
         return self.client.get('/admin/modeladmintest/author/', params)
 
+    def test_search(self):
+        response = self.get(q='Roald Dahl')
+
+        self.assertEqual(response.status_code, 200)
+
+        self.assertEqual(response.context['result_count'], 2)
+
     def test_col_extra_class_names(self):
         response = self.get()
         self.assertEqual(response.status_code, 200)

wagtail/contrib/modeladmin/views.py

@@ -1,6 +1,4 @@
-import operator
 from collections import OrderedDict
-from functools import reduce
 
 from django import forms
 from django.contrib.admin import FieldListFilter, widgets
@@ -31,7 +29,6 @@
 
 from .forms import ParentChooserForm
 
-
 try:
     from django.db.models.sql.constants import QUERY_TERMS
 except ImportError:
@@ -240,6 +237,7 @@ def dispatch(self, request, *args, **kwargs):
         self.search_fields = self.model_admin.get_search_fields(request)
         self.items_per_page = self.model_admin.list_per_page
         self.select_related = self.model_admin.list_select_related
+        self.search_handler = self.model_admin.search_handler_class(self.search_fields)
 
         # Get search parameters from the query string.
         try:
@@ -270,25 +268,8 @@ def get_buttons_for_obj(self, obj):
             obj, classnames_add=['button-small', 'button-secondary'])
 
     def get_search_results(self, request, queryset, search_term):
-        """
-        Returns a tuple containing a queryset to implement the search,
-        and a boolean indicating if the results may contain duplicates.
-        """
-        use_distinct = False
-        if self.search_fields and search_term:
-            orm_lookups = ['%s__icontains' % str(search_field)
-                           for search_field in self.search_fields]
-            for bit in search_term.split():
-                or_queries = [models.Q(**{orm_lookup: bit})
-                              for orm_lookup in orm_lookups]
-                queryset = queryset.filter(reduce(operator.or_, or_queries))
-            if not use_distinct:
-                for search_spec in orm_lookups:
-                    if lookup_needs_distinct(self.opts, search_spec):
-                        use_distinct = True
-                        break
-
-        return queryset, use_distinct
+        results, use_distinct = self.search_handler.search_queryset(queryset, search_term)
+        return results, use_distinct
 
     def lookup_allowed(self, lookup, value):
         # Check FKey lookups that are allowed, so that popups produced by
@@ -641,7 +622,8 @@ def get_context_data(self, **kwargs):
             'paginator': paginator,
             'page_obj': page_obj,
             'object_list': page_obj.object_list,
-            'user_can_create': self.permission_helper.user_can_create(user)
+            'user_can_create': self.permission_helper.user_can_create(user),
+            'show_search': self.search_handler.show_search_form,
         }
 
         if self.is_pagemodel:

wagtail/tests/modeladmintest/models.py

@@ -25,6 +25,10 @@ class Book(models.Model, index.Indexed):
     title = models.CharField(max_length=255)
     cover_image = models.ForeignKey('wagtailimages.Image', on_delete=models.SET_NULL, null=True, blank=True)
 
+    search_fields = [
+        index.SearchField('title'),
+    ]
+
     def __str__(self):
         return self.title
 

wagtail/tests/modeladmintest/wagtail_hooks.py

@@ -1,4 +1,5 @@
 from wagtail.admin.edit_handlers import FieldPanel, ObjectList, TabbedInterface
+from wagtail.contrib.modeladmin.helpers import WagtailBackendSearchHandler
 from wagtail.contrib.modeladmin.options import (
     ModelAdmin, ModelAdminGroup, ThumbnailMixin, modeladmin_register)
 from wagtail.contrib.modeladmin.views import CreateView
@@ -47,10 +48,10 @@ class BookModelAdmin(ThumbnailMixin, ModelAdmin):
     list_display = ('title', 'author', 'admin_thumb')
     list_filter = ('author', )
     ordering = ('title', )
-    search_fields = ('title', )
     inspect_view_enabled = True
     inspect_view_fields_exclude = ('title', )
     thumb_image_field_name = 'cover_image'
+    search_handler_class = WagtailBackendSearchHandler
 
     def get_extra_attrs_for_row(self, obj, context):
         return {
@@ -78,9 +79,9 @@ class EventPageAdmin(ModelAdmin):
     model = EventPage
     list_display = ('title', 'date_from', 'audience')
     list_filter = ('audience', )
-    search_fields = ('title', )
     inspect_view_enabled = True
     inspect_view_fields_exclude = ('feed_image', )
+    search_handler_class = WagtailBackendSearchHandler
 
 
 class SingleEventPageAdmin(EventPageAdmin):