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201d27f Jan 9, 2017
@toastdriven @acdha @jclgoodwin
241 lines (178 sloc) 6.84 KB
# encoding: utf-8
from __future__ import absolute_import, division, print_function, unicode_literals
from django.conf import settings
from django.core.paginator import InvalidPage, Paginator
from django.http import Http404
from django.shortcuts import render
from haystack.forms import FacetedSearchForm, ModelSearchForm
from haystack.query import EmptySearchQuerySet
RESULTS_PER_PAGE = getattr(settings, 'HAYSTACK_SEARCH_RESULTS_PER_PAGE', 20)
class SearchView(object):
template = 'search/search.html'
extra_context = {}
query = ''
results = EmptySearchQuerySet()
request = None
form = None
results_per_page = RESULTS_PER_PAGE
def __init__(self, template=None, load_all=True, form_class=None, searchqueryset=None, results_per_page=None):
self.load_all = load_all
self.form_class = form_class
self.searchqueryset = searchqueryset
if form_class is None:
self.form_class = ModelSearchForm
if not results_per_page is None:
self.results_per_page = results_per_page
if template:
self.template = template
def __call__(self, request):
"""
Generates the actual response to the search.
Relies on internal, overridable methods to construct the response.
"""
self.request = request
self.form = self.build_form()
self.query = self.get_query()
self.results = self.get_results()
return self.create_response()
def build_form(self, form_kwargs=None):
"""
Instantiates the form the class should use to process the search query.
"""
data = None
kwargs = {
'load_all': self.load_all,
}
if form_kwargs:
kwargs.update(form_kwargs)
if len(self.request.GET):
data = self.request.GET
if self.searchqueryset is not None:
kwargs['searchqueryset'] = self.searchqueryset
return self.form_class(data, **kwargs)
def get_query(self):
"""
Returns the query provided by the user.
Returns an empty string if the query is invalid.
"""
if self.form.is_valid():
return self.form.cleaned_data['q']
return ''
def get_results(self):
"""
Fetches the results via the form.
Returns an empty list if there's no query to search with.
"""
return self.form.search()
def build_page(self):
"""
Paginates the results appropriately.
In case someone does not want to use Django's built-in pagination, it
should be a simple matter to override this method to do what they would
like.
"""
try:
page_no = int(self.request.GET.get('page', 1))
except (TypeError, ValueError):
raise Http404("Not a valid number for page.")
if page_no < 1:
raise Http404("Pages should be 1 or greater.")
start_offset = (page_no - 1) * self.results_per_page
self.results[start_offset:start_offset + self.results_per_page]
paginator = Paginator(self.results, self.results_per_page)
try:
page = paginator.page(page_no)
except InvalidPage:
raise Http404("No such page!")
return (paginator, page)
def extra_context(self):
"""
Allows the addition of more context variables as needed.
Must return a dictionary.
"""
return {}
def get_context(self):
(paginator, page) = self.build_page()
context = {
'query': self.query,
'form': self.form,
'page': page,
'paginator': paginator,
'suggestion': None,
}
if hasattr(self.results, 'query') and self.results.query.backend.include_spelling:
context['suggestion'] = self.form.get_suggestion()
context.update(self.extra_context())
return context
def create_response(self):
"""
Generates the actual HttpResponse to send back to the user.
"""
context = self.get_context()
return render(self.request, self.template, context)
def search_view_factory(view_class=SearchView, *args, **kwargs):
def search_view(request):
return view_class(*args, **kwargs)(request)
return search_view
class FacetedSearchView(SearchView):
def __init__(self, *args, **kwargs):
# Needed to switch out the default form class.
if kwargs.get('form_class') is None:
kwargs['form_class'] = FacetedSearchForm
super(FacetedSearchView, self).__init__(*args, **kwargs)
def build_form(self, form_kwargs=None):
if form_kwargs is None:
form_kwargs = {}
# This way the form can always receive a list containing zero or more
# facet expressions:
form_kwargs['selected_facets'] = self.request.GET.getlist("selected_facets")
return super(FacetedSearchView, self).build_form(form_kwargs)
def extra_context(self):
extra = super(FacetedSearchView, self).extra_context()
extra['request'] = self.request
extra['facets'] = self.results.facet_counts()
return extra
def basic_search(request, template='search/search.html', load_all=True, form_class=ModelSearchForm, searchqueryset=None, extra_context=None, results_per_page=None):
"""
A more traditional view that also demonstrate an alternative
way to use Haystack.
Useful as an example of for basing heavily custom views off of.
Also has the benefit of thread-safety, which the ``SearchView`` class may
not be.
Template:: ``search/search.html``
Context::
* form
An instance of the ``form_class``. (default: ``ModelSearchForm``)
* page
The current page of search results.
* paginator
A paginator instance for the results.
* query
The query received by the form.
"""
query = ''
results = EmptySearchQuerySet()
if request.GET.get('q'):
form = form_class(request.GET, searchqueryset=searchqueryset, load_all=load_all)
if form.is_valid():
query = form.cleaned_data['q']
results = form.search()
else:
form = form_class(searchqueryset=searchqueryset, load_all=load_all)
paginator = Paginator(results, results_per_page or RESULTS_PER_PAGE)
try:
page = paginator.page(int(request.GET.get('page', 1)))
except InvalidPage:
raise Http404("No such page of results!")
context = {
'form': form,
'page': page,
'paginator': paginator,
'query': query,
'suggestion': None,
}
if results.query.backend.include_spelling:
context['suggestion'] = form.get_suggestion()
if extra_context:
context.update(extra_context)
return render(request, template, context)