def more_like_this(self,
model_instance,
additional_query_string=None,
start_offset=0,
end_offset=None,
models=None,
limit_to_registered_models=None,
result_class=None,
**kwargs):
if not self.setup_complete:
self.setup()
# Deferred models will have a different class ("RealClass_Deferred_fieldname")
# which won't be in our registry:
model_klass = model_instance._meta.concrete_model
field_name = self.content_field_name
narrow_queries = set()
narrowed_results = None
self.index = self.index.refresh()
if limit_to_registered_models is None:
limit_to_registered_models = getattr(
settings, 'HAYSTACK_LIMIT_TO_REGISTERED_MODELS', True)
if models and len(models):
model_choices = sorted([
'%s.%s' % (model._meta.app_label, model._meta.module_name)
for model in models
])
elif limit_to_registered_models:
# Using narrow queries, limit the results to only models handled
# with the current routers.
model_choices = self.build_models_list()
else:
model_choices = []
if len(model_choices) > 0:
if narrow_queries is None:
narrow_queries = set()
narrow_queries.add(' OR '.join(
['%s:%s' % (DJANGO_CT, rm) for rm in model_choices]))
if additional_query_string and additional_query_string != '*':
narrow_queries.add(additional_query_string)
narrow_searcher = None
if narrow_queries is not None:
# Potentially expensive? I don't see another way to do it in Whoosh...
narrow_searcher = self.index.searcher()
for nq in narrow_queries:
recent_narrowed_results = narrow_searcher.search(
self.parser.parse(force_unicode(nq)))
if len(recent_narrowed_results) <= 0:
return {
'results': [],
'hits': 0,
}
if narrowed_results:
narrowed_results.filter(recent_narrowed_results)
else:
narrowed_results = recent_narrowed_results
# Prevent against Whoosh throwing an error. Requires an end_offset
# greater than 0.
if not end_offset is None and end_offset <= 0:
end_offset = 1
# Determine the page.
page_num = 0
if end_offset is None:
end_offset = 1000000
if start_offset is None:
start_offset = 0
page_length = end_offset - start_offset
if page_length and page_length > 0:
page_num = start_offset / page_length
# Increment because Whoosh uses 1-based page numbers.
page_num += 1
self.index = self.index.refresh()
raw_results = EmptyResults()
if self.index.doc_count():
query = "%s:%s" % (ID, get_identifier(model_instance))
searcher = self.index.searcher()
parsed_query = self.parser.parse(query)
results = searcher.search(parsed_query)
if len(results):
raw_results = results[0].more_like_this(field_name,
top=end_offset)
# Handle the case where the results have been narrowed.
if narrowed_results is not None and hasattr(raw_results, 'filter'):
raw_results.filter(narrowed_results)
try:
raw_page = ResultsPage(raw_results, page_num, page_length)
except ValueError:
if not self.silently_fail:
raise
return {
'results': [],
'hits': 0,
'spelling_suggestion': None,
}
results = self._process_results(raw_page, result_class=result_class)
searcher.close()
if hasattr(narrow_searcher, 'close'):
narrow_searcher.close()
return results
def more_like_this(self,
model_instance,
additional_query_string=None,
start_offset=0,
end_offset=None,
models=None,
limit_to_registered_models=None,
result_class=None,
**kwargs):
if not self.setup_complete:
self.setup()
field_name = self.content_field_name
narrow_queries = set()
narrowed_results = None
self.index = self.index.refresh()
if limit_to_registered_models is None:
limit_to_registered_models = getattr(
settings, 'HAYSTACK_LIMIT_TO_REGISTERED_MODELS', True)
if models and len(models):
model_choices = sorted(get_model_ct(model) for model in models)
elif limit_to_registered_models:
# Using narrow queries, limit the results to only models handled
# with the current routers.
model_choices = self.build_models_list()
else:
model_choices = []
if len(model_choices) > 0:
if narrow_queries is None:
narrow_queries = set()
narrow_queries.add(' OR '.join(
['%s:%s' % (DJANGO_CT, rm) for rm in model_choices]))
if additional_query_string and additional_query_string != '*':
narrow_queries.add(additional_query_string)
narrow_searcher = None
if narrow_queries is not None:
# Potentially expensive? I don't see another way to do it in Whoosh...
narrow_searcher = self.index.searcher()
for nq in narrow_queries:
recent_narrowed_results = narrow_searcher.search(
self.parser.parse(force_text(nq)), limit=None)
if len(recent_narrowed_results) <= 0:
return {
'results': [],
'hits': 0,
}
if narrowed_results:
narrowed_results.filter(recent_narrowed_results)
else:
narrowed_results = recent_narrowed_results
page_num, page_length = self.calculate_page(start_offset, end_offset)
self.index = self.index.refresh()
raw_results = EmptyResults()
searcher = None
if self.index.doc_count():
query = "%s:%s" % (ID, get_identifier(model_instance))
searcher = self.index.searcher()
parsed_query = self.parser.parse(query)
results = searcher.search(parsed_query)
if len(results):
raw_results = results[0].more_like_this(field_name,
top=end_offset)
# Handle the case where the results have been narrowed.
if narrowed_results is not None and hasattr(raw_results, 'filter'):
raw_results.filter(narrowed_results)
try:
raw_page = ResultsPage(raw_results, page_num, page_length)
except ValueError:
if not self.silently_fail:
raise
return {
'results': [],
'hits': 0,
'spelling_suggestion': None,
}
# Because as of Whoosh 2.5.1, it will return the wrong page of
# results if you request something too high. :(
if raw_page.pagenum < page_num:
return {
'results': [],
'hits': 0,
'spelling_suggestion': None,
}
results = self._process_results(raw_page, result_class=result_class)
if searcher:
searcher.close()
if hasattr(narrow_searcher, 'close'):
narrow_searcher.close()
return results
def search(self,
query_string,
sort_by=None,
start_offset=0,
end_offset=None,
fields='',
highlight=False,
facets=None,
date_facets=None,
query_facets=None,
narrow_queries=None,
spelling_query=None,
within=None,
dwithin=None,
distance_point=None,
models=None,
limit_to_registered_models=None,
result_class=None,
**kwargs):
if not self.setup_complete:
self.setup()
# A zero length query should return no results.
if len(query_string) == 0:
return {
'results': [],
'hits': 0,
}
query_string = force_unicode(query_string)
# A one-character query (non-wildcard) gets nabbed by a stopwords
# filter and should yield zero results.
if len(query_string) <= 1 and query_string != u'*':
return {
'results': [],
'hits': 0,
}
reverse = False
if sort_by is not None:
# Determine if we need to reverse the results and if Whoosh can
# handle what it's being asked to sort by. Reversing is an
# all-or-nothing action, unfortunately.
sort_by_list = []
reverse_counter = 0
for order_by in sort_by:
if order_by.startswith('-'):
reverse_counter += 1
if len(sort_by) > 1 and reverse_counter > 1:
raise SearchBackendError(
"Whoosh does not handle more than one field and any field being ordered in reverse."
)
for order_by in sort_by:
if order_by.startswith('-'):
sort_by_list.append(order_by[1:])
if len(sort_by_list) == 1:
reverse = True
else:
sort_by_list.append(order_by)
if len(sort_by_list) == 1:
reverse = False
sort_by = sort_by_list[0]
if facets is not None:
warnings.warn("Whoosh does not handle faceting.",
Warning,
stacklevel=2)
if date_facets is not None:
warnings.warn("Whoosh does not handle date faceting.",
Warning,
stacklevel=2)
if query_facets is not None:
warnings.warn("Whoosh does not handle query faceting.",
Warning,
stacklevel=2)
narrowed_results = None
self.index = self.index.refresh()
if limit_to_registered_models is None:
limit_to_registered_models = getattr(
settings, 'HAYSTACK_LIMIT_TO_REGISTERED_MODELS', True)
if models and len(models):
model_choices = sorted([
'%s.%s' % (model._meta.app_label, model._meta.module_name)
for model in models
])
elif limit_to_registered_models:
# Using narrow queries, limit the results to only models handled
# with the current routers.
model_choices = self.build_models_list()
else:
model_choices = []
if len(model_choices) > 0:
if narrow_queries is None:
narrow_queries = set()
narrow_queries.add(' OR '.join(
['%s:%s' % (DJANGO_CT, rm) for rm in model_choices]))
narrow_searcher = None
if narrow_queries is not None:
# Potentially expensive? I don't see another way to do it in Whoosh...
narrow_searcher = self.index.searcher()
for nq in narrow_queries:
recent_narrowed_results = narrow_searcher.search(
self.parser.parse(force_unicode(nq)))
if len(recent_narrowed_results) <= 0:
return {
'results': [],
'hits': 0,
}
if narrowed_results:
narrowed_results.filter(recent_narrowed_results)
else:
narrowed_results = recent_narrowed_results
self.index = self.index.refresh()
if self.index.doc_count():
searcher = self.index.searcher()
parsed_query = self.parser.parse(query_string)
# In the event of an invalid/stopworded query, recover gracefully.
if parsed_query is None:
return {
'results': [],
'hits': 0,
}
# Prevent against Whoosh throwing an error. Requires an end_offset
# greater than 0.
if not end_offset is None and end_offset <= 0:
end_offset = 1
raw_results = searcher.search(parsed_query,
limit=end_offset,
sortedby=sort_by,
reverse=reverse)
# Handle the case where the results have been narrowed.
if narrowed_results is not None:
raw_results.filter(narrowed_results)
# Determine the page.
page_num = 0
if end_offset is None:
end_offset = 1000000
if start_offset is None:
start_offset = 0
page_length = end_offset - start_offset
if page_length and page_length > 0:
page_num = start_offset / page_length
# Increment because Whoosh uses 1-based page numbers.
page_num += 1
try:
raw_page = ResultsPage(raw_results, page_num, page_length)
except ValueError:
if not self.silently_fail:
raise
return {
'results': [],
'hits': 0,
'spelling_suggestion': None,
}
results = self._process_results(raw_page,
highlight=highlight,
query_string=query_string,
spelling_query=spelling_query,
result_class=result_class)
searcher.close()
if hasattr(narrow_searcher, 'close'):
narrow_searcher.close()
return results
else:
if self.include_spelling:
if spelling_query:
spelling_suggestion = self.create_spelling_suggestion(
spelling_query)
else:
spelling_suggestion = self.create_spelling_suggestion(
query_string)
else:
spelling_suggestion = None
return {
'results': [],
'hits': 0,
'spelling_suggestion': spelling_suggestion,
}