def _get_cache(self, cache_filename, cache_pathname):
# Remove file on disc if there is one
try:
if os.path.exists(cache_pathname):
os.remove(cache_pathname)
except Exception as ex:
raise Exception('Removal of old cache file %s failed.' % cache_pathname) from ex
if not self.is_postgre_sql:
sql_statement = "SELECT PARQUET_FILE FROM %s.%s WHERE ENTITY_TYPE_ID = ? AND PARQUET_NAME = ?" % (
self.quoted_schema, self.quoted_cache_tablename)
stmt = ibm_db.prepare(self.db_connection, sql_statement)
try:
ibm_db.bind_param(stmt, 1, self.entity_type_id)
ibm_db.bind_param(stmt, 2, cache_filename)
ibm_db.execute(stmt)
row = ibm_db.fetch_tuple(stmt)
if row is False:
row = None
except Exception as ex:
raise Exception(
'Retrieval of cache %s failed with sql statement "%s"' % (cache_filename, sql_statement)) from ex
finally:
ibm_db.free_result(stmt)
else:
sql_statement = 'SELECT parquet_file FROM %s.%s' % (self.quoted_schema, self.quoted_cache_tablename)
sql_statement += ' WHERE entity_type_id = %s AND parquet_name = %s'
try:
row = dbhelper.execute_postgre_sql_select_query(self.db_connection, sql_statement,
(self.entity_type_id, cache_filename),
fetch_one_only=True)
except Exception as ex:
raise Exception(
'Retrieval of cache %s failed with sql statement "%s"' % (cache_filename, sql_statement)) from ex
cache_found = False
if row is not None:
cache_found = True
parquet = row[0]
if parquet is not None and len(parquet) > 0:
try:
f = open(cache_pathname, "wb")
try:
f.write(parquet)
logger.info('Cache %s has been retrieved from table %s.%s and stored under %s' % (
cache_filename, self.quoted_schema, self.quoted_cache_tablename, cache_pathname))
finally:
f.close()
except Exception as ex:
raise Exception('Writing cache file %s to disc failed.' % cache_pathname) from ex
else:
logger.info('The cache %s is empty' % cache_filename)
else:
logger.info('No cache found for %s' % cache_filename)
return cache_found
def retrieve_model(self, model_name, deserialize=True):
if not self.is_postgre_sql:
sql_statement = "SELECT MODEL FROM %s.%s WHERE ENTITY_TYPE_ID = ? AND MODEL_NAME = ?" % (
self.quoted_schema, self.quoted_store_tablename)
stmt = ibm_db.prepare(self.db_connection, sql_statement)
try:
ibm_db.bind_param(stmt, 1, self.entity_type_id)
ibm_db.bind_param(stmt, 2, model_name)
ibm_db.execute(stmt)
row = ibm_db.fetch_tuple(stmt)
if row is False:
model = None
else:
model = row[0]
except Exception as ex:
raise Exception(
'Retrieval of model %s failed with sql statement "%s"' % (model_name, sql_statement)) from ex
finally:
ibm_db.free_result(stmt)
else:
sql_statement = 'SELECT model FROM %s.%s' % (self.quoted_schema, self.quoted_store_tablename)
sql_statement += ' WHERE entity_type_id = %s AND model_name = %s'
try:
row = dbhelper.execute_postgre_sql_select_query(self.db_connection, sql_statement,
(self.entity_type_id, model_name), fetch_one_only=True)
if row is None:
model = None
else:
model = bytes(row[0])
except Exception as ex:
raise Exception(
'Retrieval of model %s failed with sql statement "%s"' % (model_name, sql_statement)) from ex
if model is not None:
logger.info('Model %s of size %d bytes has been retrieved from table %s.%s' % (
model_name, len(model) if model is not None else 0, self.quoted_schema, self.quoted_store_tablename))
else:
logger.info('Model %s does not exist in table %s.%s' % (
model_name, self.quoted_schema, self.quoted_store_tablename))
if model is not None and deserialize:
try:
model = pickle.loads(model)
except Exception as ex:
raise Exception(
'Deserialization of model %s that has been retrieved from ModelStore failed.' % model_name) from ex
return model