def query(self, dataset_key, query, query_type="sql", parameters=None):
"""Query an existing dataset
:param dataset_key: Dataset identifier, in the form of owner/id or of
a url
:type dataset_key: str
:param query: SQL or SPARQL query
:type query: str
:param query_type: The type of the query. Must be either 'sql' or
'sparql'. (Default value = "sql")
:type query_type: {'sql', 'sparql'}, optional
:param parameters: parameters to the query - if SPARQL query, this
should be a dict containing named parameters, if SQL query,then
this should be a list containing positional parameters.
Boolean values will be converted to xsd:boolean, Integer values to
xsd:integer, and other Numeric values to xsd:decimal. Anything
else is treated as a String literal (Default value = None)
:type parameters: query parameters, optional
:returns: Object containing the results of the query
:rtype: Results
:raises RuntimeError: If a server error occurs
"""
# TODO Move network request to RestApiClient
owner_id, dataset_id = parse_dataset_key(dataset_key)
params = {"query": query}
if parameters and query_type == "sparql":
# if SPARQL, then the parameters should be a Mapping containing
# named parameters
params["parameters"] = ",".join([
"{}={}".format(k, convert_to_sparql_literal(parameters[k]))
for k in parameters.keys()
])
elif parameters and query_type == "sql":
# if SQL, then the parameters should be an array with positional
# parameters, need to unwind them to $data_world_paramN for each
# 0-indexed position N
parameters = {
"$data_world_param{}".format(i): x
for i, x in enumerate(parameters)
}
params["parameters"] = ",".join([
"{}={}".format(k, convert_to_sparql_literal(parameters[k]))
for k in parameters.keys()
])
url = "{0}://{1}/{2}/{3}/{4}".format(self._protocol, self._query_host,
query_type, owner_id, dataset_id)
headers = {
'User-Agent': _user_agent(),
'Accept': 'application/sparql-results+json',
'Authorization': 'Bearer {0}'.format(self._config.auth_token)
}
response = requests.get(url, params=params, headers=headers)
if response.status_code == 200:
return QueryResults(response.json())
raise RuntimeError('Error executing query: {}'.format(
response.content))
def query(self, dataset_key, query, query_type="sql"):
"""Query an existing dataset
Parameters
----------
dataset_key : str
Dataset identifier, in the form of owner/id or of a url
query : str
SQL or SPARQL query
query_type : {'sql', 'sparql'}, optional
The type of the query. Must be either 'sql' or 'sparql'.
Returns
-------
Results
Object containing the results of the query
Raises
------
RuntimeError
If a server error occurs
"""
# TODO Move network request to RestApiClient
owner_id, dataset_id = parse_dataset_key(dataset_key)
params = {"query": query}
url = "{0}://{1}/{2}/{3}/{4}".format(self._protocol, self._query_host,
query_type, owner_id, dataset_id)
headers = {
'User-Agent': _user_agent(),
'Accept': 'application/sparql-results+json',
'Authorization': 'Bearer {0}'.format(self._config.auth_token)
}
response = requests.get(url, params=params, headers=headers)
if response.status_code == 200:
return QueryResults(response.json())
raise RuntimeError('Error executing query: {}'.format(
response.content))
def query_results(self, query_result_example):
return QueryResults(query_result_example)