Wagtail default search not working with not english fields

Question

I'm using default Database Backend for search function in my project:

from __future__ import absolute_import, unicode_literals

from django.core.paginator import EmptyPage, PageNotAnInteger, Paginator
from django.shortcuts import render

from home.models import BlogPage, get_all_tags
from wagtail.wagtailsearch.models import Query


def search(request):
    search_query = request.GET.get('query', None)
    page = request.GET.get('page', 1)

    # Search
    if search_query:
        search_results = BlogPage.objects.live().search(search_query)
        query = Query.get(search_query)

        # Record hit
        query.add_hit()
    else:
        search_results = BlogPage.objects.none()

    # Pagination
    paginator = Paginator(search_results, 10)
    try:
        search_results = paginator.page(page)
    except PageNotAnInteger:
        search_results = paginator.page(1)
    except EmptyPage:
        search_results = paginator.page(paginator.num_pages)

    return render(request, 'search/search.html', {
        'search_query': search_query,
        'blogpages': search_results,
        'tags': get_all_tags()
    })

BlogPage:

class BlogPage(Page):
    date = models.DateField("Post date")
    intro = models.CharField(max_length=250)
    body = StreamField([
        ('heading', blocks.CharBlock(classname="full title")),
        ('paragraph', blocks.RichTextBlock()),
        ('image', ImageChooserBlock()),
        ('code', CodeBlock()),
    ])
    tags = ClusterTaggableManager(through=BlogPageTag, blank=True)

    search_fields = Page.search_fields + [
        index.SearchField('intro'),
        index.SearchField('body'),
    ]
    ...

And search is working well only if body fields in BlogPage model are in english,if I try to use some russian words in the body fields then it don't search anything. I looked at database and I see that BlogPage has body field like this:

[{"value": "\u0442\u0435\u0441\u0442\u043e\u0432\u044b\u0439", "id": "3343151a-edbc-4165-89f2-ce766922d68e", "type": "heading"}, {"value": "<p>\u0442\u0435\u0441\u0442\u0438\u043f\u0440</p>", "id": "22d3818d-8c69-4d72-967e-7c1f807e80b2", "type": "paragraph"}]

So, the problem is wagtail saves Streamfield fields as unicode characters, if I manually change in phpmyadmin to this:

[{"value": "Тест", "id": "3343151a-edbc-4165-89f2-ce766922d68e", "type": "heading"}, {"value": "<p>Тестовый</p>", "id": "22d3818d-8c69-4d72-967e-7c1f807e80b2", "type": "paragraph"}]

Then search start working, so maybe anyone knows how to prevent wagtail from saving Streamfield fields in unicode?

Answer 1

I hate this workaround, but I decided just to add another fields search_body and search_intro and then search using them:

class BlogPage(Page):
    date = models.DateField("Post date")
    intro = models.CharField(max_length=250)
    body = StreamField([
        ('heading', blocks.CharBlock(classname="full title")),
        ('paragraph', blocks.RichTextBlock()),
        ('image', ImageChooserBlock()),
        ('code', CodeBlock()),
    ])
    search_intro = models.CharField(max_length=250)
    search_body = models.CharField(max_length=50000)
    tags = ClusterTaggableManager(through=BlogPageTag, blank=True)

    def main_image(self):
        gallery_item = self.gallery_images.first()
        if gallery_item:
            return gallery_item.image
        else:
            return None

    def get_context(self, request):
        context = super(BlogPage, self).get_context(request)
        context['tags'] = get_all_tags()
        context['page_url'] = urllib.parse.urljoin(BASE_URL, self.url)
        return context

    def save(self, *args, **kwargs):
        if self.body.stream_data and isinstance(
                self.body.stream_data[0], tuple):
            self.search_body = ''
            for block in self.body.stream_data:
                if len(block) >= 2:
                    self.search_body += str(block[1])
        self.search_intro = self.intro.lower()
        self.search_body = self.search_body.lower()
        return super().save(*args, **kwargs)

    search_fields = Page.search_fields + [
        index.SearchField('search_intro'),
        index.SearchField('search_body'),
    ]
    ...

search/views.py:

def search(request):
    search_query = request.GET.get('query', None)
    page = request.GET.get('page', 1)

    # Search
    if search_query:
        search_results = BlogPage.objects.live().search(search_query.lower())
        query = Query.get(search_query)
    ...

Answer 2

Alexey, thank you!

But I got double call of save method.

And I should use this code:

    def save(self, *args, **kwargs):
    search_body = ''
    if self.blog_post_body.stream_data and isinstance(
            self.blog_post_body.stream_data[0], dict):
        for block in self.blog_post_body.stream_data:
            if block.get('type', '') in ('some_header', 'some_text'):
                search_body += str(block['value'])
    self.search_body = search_body
    super(BlogPost, self).save(*args, **kwargs)

Answer 3

StreamField uses DjangoJSONEncoder to encode JSON, which has ensure_ascii = True. Then you will see the Unicode presented as "\u....". The default db search backend simply uses a database text match and will fail with the query with non-ASCII keywords.

    def get_prep_value(self, value):
        if isinstance(value, StreamValue) and not(value) and value.raw_text is not None:
            # An empty StreamValue with a nonempty raw_text attribute should have that
            # raw_text attribute written back to the db. (This is probably only useful
            # for reverse migrations that convert StreamField data back into plain text
            # fields.)
            return value.raw_text
        else:
            return json.dumps(self.stream_block.get_prep_value(value), cls=DjangoJSONEncoder)

You need to subclass StreamField and provide a custom JSONEncoder with ensure_ascii=False. But then you need to make sure your database can handle the utf-8 string by default. (Should be fine for PostgreSQL).

If you switch to another backend like the PG search backend. It will extract text from StreamField when building indexes (introduced by https://github.com/wagtail/wagtail/pull/982). You won't have a problem.