"EndPointNotFound: impossible to connect with the endpoint"
means the Python code could not establish an HTTP connection to the server.
Usually means the server is not running or the URL used is not correct.
Andy
On 24/03/2021 12:32, Murphy wrote:
when I try to use jena-fuseki in Python IDE, I use SPARQLWrapper，the code is
like this:
# encoding=utf-8
from SPARQLWrapper import SPARQLWrapper, JSON
from collections import OrderedDict
class JenaFuseki:
def __init__(self, endpoint_url='http://localhost:3030/dscout/query'):
self.sparql_conn = SPARQLWrapper(endpoint_url)
def get_sparql_result(self, query):
self.sparql_conn.setQuery(query)
self.sparql_conn.setReturnFormat(JSON)
return self.sparql_conn.query().convert()
@staticmethod
def parse_result(query_result):
try:
query_head = query_result['head']['vars']
query_results = list()
for r in query_result['results']['bindings']:
temp_dict = OrderedDict()
for h in query_head:
temp_dict[h] = r[h]['value']
query_results.append(temp_dict)
return query_head, query_results
except KeyError:
return None, query_result['boolean']
def print_result_to_string(self, query_result):
query_head, query_result = self.parse_result(query_result)
if query_head is None:
if query_result is True:
print ('Yes')
else:
print ('False')
print()
else:
for h in query_head:
print (h, ' '*5,)
print()
for qr in query_result:
for _, value in qr.iteritems():
print (value, ' ',)
print()
def get_sparql_result_value(self, query_result):
query_head, query_result = self.parse_result(query_result)
if query_head is None:
return query_result
else:
values = list()
for qr in query_result:
for _, value in qr.items():
values.append(value)
return values
# TODO test
if __name__ == '__main__':
fuseki = JenaFuseki()
my_query = """
PREFIX : <http://dsc.nlp-bigdatalab.org:8086/>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
SELECT * WHERE {
:老年膀胱癌 rdf:type ?o.
}
"""
result = fuseki.get_sparql_result(my_query)
fuseki.print_result_to_string(result)
but I get this after running the code above:
Traceback (most recent call last):
File "D:/zhou/Pycharms/KGQA-medicine-v1/kgqa/KB_query/jena_sparql_endpoint.py",
line 102, in <module>
result = fuseki.get_sparql_result(my_query)
File
"D:/zhou/Pycharms/KGQA-medicine-v1/kgqa/KB_query/jena_sparql_endpoint.py", line
22, in get_sparql_result
return self.sparql_conn.query().convert()
File
"D:\ZhouProgram\Anaconda3\envs\pytorch\lib\site-packages\SPARQLWrapper\Wrapper.py",
line 687, in query
return QueryResult(self._query())
File
"D:\ZhouProgram\Anaconda3\envs\pytorch\lib\site-packages\SPARQLWrapper\Wrapper.py",
line 663, in _query
raise EndPointNotFound(e.read())
SPARQLWrapper.SPARQLExceptions.EndPointNotFound: EndPointNotFound: it was
impossible to connect with the endpoint in that address, check if it is correct.
Response:
b'Error 404: Not Found\n'
Process finished with exit code 1
I think the main reason is that I have not grasped the code. so, may I get a
similar tutorial about this？
but It is better for me to get the direct answer that explains why it does not
work
thanks very much
