Django views.py updating a pagination from a category selection in a class-based view

Question

The problem is a bit complex. In fact, I am not trying to re-invent the wheel and since the back-end dev left I am trying my best not to destroy his code.

But, I think this time I will need to change a lot of things. Or maybe the answer is quite simple and my lake of experience play against me.

Basically, I have a list of articles that you can sort by categories.

I sorted those this way in the URLs:

urlpatterns = patterns(
  '',
  url(r'^$', ArticleListView.as_view(), name='articles-list'),
  url(r'^source/(?P<source>[\w\.@+-]+)/$', SourceEntriesView.as_view(), name='articles-source'),
  url(r'^date/(?P<daterealization>[\w\.@+-]+)/$', DateEntriesView.as_view(), name='articles-date'),
  url(r'^country/(?P<region>[\w\.@+-]+)/$', RegionEntriesView.as_view(), name='articles-region'),
  url(r'^global/$', GlobalEntriesView.as_view(), name='articles-global'),
)

and the main URL is mydomain.com/en/press/

So basically, when I try to sort my articles by sources, for example, I have my article by this category displaying. But the pagination still has all the article.

So, if there is only one article in the category, this only article is showing but my "loadMore button" isn't disabled since it's considering that there are more articles behind.

Here are the principals views.py base-class view, first the base:

class BaseArticleListView(ListView):
"""
Base article list view for manage ajax navigation
"""
model = Article
context_object_name = 'article_list'
template_name = 'base_templates/template_press.html'
paginate_by = get_setting('PAGINATION')

def get_load_more_url(self, request, context):
    args = request.GET.copy()
    page_obj = context.get('page_obj', None)

    if not page_obj or not page_obj.has_next():
        return ''

    args[self.page_kwarg] = page_obj.next_page_number()

    return '?{}'.format(args.urlencode())

def render_to_json_response(self, context, **response_kwargs):
    if 'current_app' not in context:
        context['current_app'] = resolve(self.request.path).namespace

    c = RequestContext(self.request, context)

    html_items_list = render_to_string(
        'base_templates/template_press.html',
        context,
        context_instance=c)

    html_items_list = html_items_list.strip()

    json_response = {
        'html_items_list': html_items_list,
        'load_more_url': self.get_load_more_url(
            self.request,
            context)
    }

    return JsonResponse(json_response)

And the generic list entry view :

#Main article display view 
class ArticleListView(FormMixin, BaseArticleView, BaseArticleListView, ContextSourcesMixin):
  model = Article
  view_url_name = 'djangocms_press:articles-list'
  form_class = SourcesRegionsFilterForm

  def get_form_kwargs(self):
    return {
        'initial': self.get_initial(),
        'prefix': self.get_prefix(),
        'data': self.request.GET or None,
        'request': self.request,
    }

  def get(self, request, *args, **kwargs):
    """
    Handle the form submissions to filter by Sources and regions
    First_object is use for pagination
    """
    context = {}

    self.object_list = self.get_queryset().order_by("-date_realization")

    first_object = 0

    if 'article' in self.request.GET:
        try:
            project_id = int(request.GET['article'])
            context['article_render'] = self.object_list.get(pk=project_id)
        except (Article.DoesNotExist, ValueError):
            pass

    form = self.get_form(self.form_class)

    if form.is_valid():
        if form.cleaned_data['regions']:
            self.object_list = self.object_list.filter(
                Q(regions__continent=form.cleaned_data['regions']) | Q(global_regions=True)).distinct()

    context.update(self.get_context_data(form=form))

    context[self.context_object_name] = context['object_list']

    source_qs = ArticleSource.objects.active_translations(get_language()).order_by('translations__name')
    date_realization_for_articles = Article.objects.values_list('date_realization',
                                                        flat=True).distinct()
    region_for_articles = Country.objects.exclude(regions_press_article=None).order_by('name')

    context['load_more_url'] = self.get_load_more_url(request, context)
    context['dates_realization'] = date_realization_for_articles.dates('date_realization', 'month', order="DESC")
    context['sources_list'] = source_qs
    context['regions_list'] = region_for_articles

    return self.render_to_response(context)

  def render_to_json_response(self, context, **response_kwargs):
    if 'current_app' not in context:
        context['current_app'] = resolve(self.request.path).namespace

    c = RequestContext(self.request, context)

    html_items_list = render_to_string(
        'base_templates/template_press.html',
        context,
        context_instance=c)

    html_items_list = html_items_list.strip()

    json_response = {
        'html_items_list': html_items_list,
        'load_more_url': self.get_load_more_url(self.request, context),
    }

    return JsonResponse(json_response)

  def render_to_response(self, context):
    if self.request.is_ajax():
        response = self.render_to_json_response(context)
    else:
        response = super(ArticleListView, self).render_to_response(context)
    return response

And you can see that the loadmore button is update at this line :

context['load_more_url'] = self.get_load_more_url(request, context)

end FINALLY the class that manage the sources sorted :

class SourceEntriesView(ContextSourcesMixin, BaseArticleView, BaseArticleListView):
  context_object_name = 'article_list'
  template_name = 'base_templates/template_press.html'
  _source = None
  view_url_name = 'djangocms_press:articles-source'

  def get(self, *args, **kwargs):
    # submit object to cms toolbar to get correct language switcher behavior
    if hasattr(self.request, 'toolbar'):
        self.request.toolbar.set_object(self.source)
    return super(SourceEntriesView, self).get(*args, **kwargs)

  @property
  def source(self):
    if not self._source:
        try:
            source_qs = ArticleSource.objects.active_translations(
                get_language(),
                slug=self.kwargs['source']
            )

            #source_qs = source_qs.filter(site=Site.objects.get_current().pk)
            self._source = source_qs.latest('pk')

        except ArticleSource.DoesNotExist:
            raise Http404("ArticleSource does not exist for this site")
    return self._source

  def get_queryset(self):
    qs = super(SourceEntriesView, self).get_queryset()
    if 'source' in self.kwargs:
        qs = qs.filter(sources__pk=self.source.pk)
    return qs

  def get_context_data(self, **kwargs):
    kwargs['source'] = self.source
    context = super(SourceEntriesView, self).get_context_data(**kwargs)
    return context

So, this last class is call in ajax - from the URL - when you select a source. But how to update the load more button from here? I am so lost.

After reading documentation about pagination and base-class view, my conclusion would be to delete those line. But I am afraid to break everything and that I won't be able to make it work properly.

So, my question is what would be the best way of updating a pagination for sorting by some categories an object?

Thank you in advance, at least for the time spent on my request.

Answer 1

So, as it was quite complexe (but finally not) I rewrote everything.

And now it's working, back on the good old day (erase / code again).

Thanks to all the persons who spent time on reading my request, even if unfortunately no one could give an answer !