def _get_element_result(self, exec_query_resp):
"""
Get the response from rasserver for query which doesn't return array which can be converted to Numpy ndarray
e.g: select 1 + 2, select {1, 2, 3}
:return: array of results if server returns multiple elements or just 1 result if only 1 element
"""
rpcstatus = 0
band_types = get_type_structure_from_string(
exec_query_resp.type_structure)
result_arr = ResultArray(band_types['type'], is_object=False)
while rpcstatus == 0:
elemresp = rassrvr_get_next_element(
self.transaction.database.stub,
self.transaction.database.connection.session.clientId)
rpcstatus = elemresp.status
if rpcstatus == 2:
raise Exception(
"getNextElement - no transfer or empty element")
# e.g: select 2 + 3, select complex(3, 5)
result = convert_binary_data_stream(band_types, elemresp.data)
result_arr.add_data(result)
return result_arr
def _get_collection_result(self, exec_query_resp):
"""
Parse the string binary containing data (encoded, unencoded) from rasql to objects which later can be
translated to numpy array.
Or returns the list of rasdaman collections in RASBASE.
:return: ResultArray object
"""
spatial_domain = get_spatial_domain_from_type_structure(
exec_query_resp.type_structure)
band_types = get_type_structure_from_string(
exec_query_resp.type_structure)
# concatenate all the binary strings to one string to be decoded as Numpy ndarray buffer
data_list = self.__get_array_result_mdd()
data = b''.join(data_list)
data_type = band_types["type"]
# NOTE: unencoded result array is nD+ numpy array. If number of bands > 1 then the number of dimensions + 1
number_of_bands = 1
if data_type == "struct":
data_type = band_types["sub_type"]["types"][0]
number_of_bands = len(band_types["sub_type"]["types"])
res_array = ResultArray(data_type, spatial_domain, number_of_bands)
res_array.add_data(data)
return res_array
def _get_list_collection(self):
"""
Return the list of collection names from RASBASE for query (select c from RAS_COLLECTIONNAMES as c)
:return: list of string collection names
"""
result_array = ResultArray("string")
for r in self.__get_array_result_mdd():
result_array.add_data(encoded_bytes_to_str(r))
return result_array
def execute_read(self):
"""
Executes the query with read permission and returns back a result
:return: the resulting array returned by the query
:rtype: result object according to query
"""
exec_query_resp = rassrvr_execute_query(
self.transaction.database.stub,
self.transaction.database.connection.session.clientId,
self.query_str)
if exec_query_resp.status == 4 or exec_query_resp.status == 5:
error_message = ExceptionFactories.create_error_message(
exec_query_resp.err_no, exec_query_resp.line_no,
exec_query_resp.col_no, exec_query_resp.token)
raise Exception(
"Error executing query '{}', error message '{}'".format(
self.query_str, error_message))
elif exec_query_resp.status == 0:
tmp_query = self.query_str.upper()
# e.g: query: select c from RAS_COLLECTIONNAMES as c
if "RAS_COLLECTIONNAMES" in tmp_query or \
"RAS_STRUCT_TYPES" in tmp_query or \
"RAS_MARRAY_TYPES" in tmp_query or \
"RAS_SET_TYPES" in tmp_query or \
"DBINFO" in tmp_query:
return self._get_list_collection()
# e.g: query: select c + 1 from test_mr as c, select encode(c, "png") from test_mr as c
return self._get_collection_result(exec_query_resp)
elif exec_query_resp.status == 1:
# e.g: query: select complex(35, 56), select sdom(c) from test_mr as c, select {1, 2, 3}
return self._get_element_result(exec_query_resp)
elif exec_query_resp.status == 2:
# Query can return empty collection (e.g: select c from c where all_cells( c > 20 )) which returns empty
return ResultArray("string") # empty array
else:
raise Exception("Unknown status code: " +
str(exec_query_resp.status) +
" returned by ExecuteQuery")