class WhooshSearchInterface(BaseSearchInterface):
"""
A search interface making use of the Whoosh indexing library - and the ifind search components.
Set model = 0 for TFIDIF
Set model = 1 for BM25 (defaults to b=0.75), set pval to change b.
Set model = 2 for PL2 (defaults to c=10.), set pval to change c.
"""
def __init__(self, whoosh_index_dir, model=2, implicit_or=True, pval=None):
super(WhooshSearchInterface, self).__init__()
log.debug("Whoosh Index to open: {0}".format(whoosh_index_dir))
self.__index = open_dir(whoosh_index_dir)
self.__reader = self.__index.reader()
self.__engine = Whooshtrec(whoosh_index_dir=whoosh_index_dir,model=model,implicit_or=implicit_or)
if pval:
self.__engine.set_model(model, pval)
def issue_query(self, query, top=100):
"""
Allows one to issue a query to the underlying search engine. Takes an ifind Query object.
"""
query.top = top
response = self.__engine.search(query)
self._last_query = query
self._last_response = response
return response
def get_document(self, document_id):
"""
Retrieves a Document object for the given document specified by parameter document_id.
"""
fields = self.__reader.stored_fields(int(document_id))
title = fields['title']
content = fields['content']
document_num = fields['docid']
document_date = fields['timedate']
document_source = fields['source']
document = Document(id=document_id, title=title, content=content)
document.date = document_date
document.doc_id = document_num
document.source = document_source
return document
class WhooshSearchInterface(BaseSearchInterface):
"""
A search interface making use of the Whoosh indexing library - and the ifind search components.
Set model = 0 for TFIDIF
Set model = 1 for BM25 (defaults to b=0.75), set pval to change b.
Set model = 2 for PL2 (defaults to c=10.), set pval to change c.
"""
def __init__(self,
whoosh_index_dir,
model=2,
implicit_or=True,
pval=None,
frag_type=2,
frag_size=2,
frag_surround=40,
host=None,
port=0):
super(WhooshSearchInterface, self).__init__()
log.debug("Whoosh Index to open: {0}".format(whoosh_index_dir))
self.__index = open_dir(whoosh_index_dir)
self.__reader = self.__index.reader()
self.__redis_conn = None
if host is None:
self.__engine = Whooshtrec(whoosh_index_dir=whoosh_index_dir,
model=model,
implicit_or=implicit_or)
else:
self.__engine = Whooshtrec(whoosh_index_dir=whoosh_index_dir,
model=model,
implicit_or=implicit_or,
cache='engine',
host=host,
port=port)
# Update (2017-05-02) for snippet fragment tweaking.
# SIGIR Study (2017) uses frag_type==1 (2 doesn't give sensible results), surround==40, snippet_sizes==2,0,1,4
self.__engine.snippet_size = frag_size
self.__engine.set_fragmenter(frag_type=frag_type,
surround=frag_surround)
if pval:
self.__engine.set_model(model, pval)
def issue_query(self, query, top=100):
"""
Allows one to issue a query to the underlying search engine. Takes an ifind Query object.
"""
query.top = top
response = self.__engine.search(query)
self._last_query = query
self._last_response = response
return response
def get_document(self, document_id):
"""
Retrieves a Document object for the given document specified by parameter document_id.
"""
fields = self.__reader.stored_fields(int(document_id))
title = fields['title']
content = fields['content']
document_num = fields['docid']
document_date = fields['timedate']
document_source = fields['source']
document = Document(id=document_id, title=title, content=content)
document.date = document_date
document.doc_id = document_num
document.source = document_source
return document
