Passing List of Params while Calling REST API using PythonUDx

Could you elaborate more on the use case and data flow? If this is a parameter to the UDx, I would think you could convert to string and pass as VARCHAR. Or is it used inside the UDx? If so, return as string / VARCHAR, then parse into a flex table or flex column.

@Bryan_H said:
Could you elaborate more on the use case and data flow? If this is a parameter to the UDx, I would think you could convert to string and pass as VARCHAR. Or is it used inside the UDx? If so, return as string / VARCHAR, then parse into a flex table or flex column.

Hi Bryan,
arg1=[{},{},{}]
Let say, my udx function is GetApiResponse(arg1). In this scenario, how it will work as I want to pass list as a param to Udx function.
Thanks !!

How about this python script "json_demo.py":

import json
import vertica_sdk

class json_demo(vertica_sdk.ScalarFunction):
def processBlock(self, server_interface, arg_reader, res_writer):
while True:
x = arg_reader.getString(0)
d = json.loads(x)
res_writer.setString(d["success"]+" "+str(d["status"])+" "+d["message"])
res_writer.next()
if not arg_reader.next():
break

class json_demo_factory(vertica_sdk.ScalarFunctionFactory):
def getPrototype(self, srv_interface, arg_types, return_type):
arg_types.addVarchar()
return_type.addVarchar()
def getReturnType(self, srv_interface, arg_types, return_type):
return_type.addVarchar(80)
def createScalarFunction(self, srv):
return json_demo()

Use this SQL to test:

\set libfile '\''`pwd`'/json_demo.py\''
CREATE LIBRARY JsonDemoFunctions AS :libfile LANGUAGE 'Python';

-- Step 2: Create functions
CREATE FUNCTION json_demo AS NAME 'json_demo_factory' LIBRARY JsonDemoFunctions;

-- Step 3: Test
SELECT json_demo('{"success": "true", "status": 200, "message": "Hello"}');

-- Step 4: Clean up
DROP LIBRARY JsonDemoFunctions CASCADE;

@Bryan_H said:
How about this python script "json_demo.py":

import json
import vertica_sdk

class json_demo(vertica_sdk.ScalarFunction):
def processBlock(self, server_interface, arg_reader, res_writer):
while True:
x = arg_reader.getString(0)
d = json.loads(x)
res_writer.setString(d["success"]+" "+str(d["status"])+" "+d["message"])
res_writer.next()
if not arg_reader.next():
break

class json_demo_factory(vertica_sdk.ScalarFunctionFactory):
def getPrototype(self, srv_interface, arg_types, return_type):
arg_types.addVarchar()
return_type.addVarchar()
def getReturnType(self, srv_interface, arg_types, return_type):
return_type.addVarchar(80)
def createScalarFunction(self, srv):
return json_demo()

Use this SQL to test:

\set libfile '\''`pwd`'/json_demo.py\''
CREATE LIBRARY JsonDemoFunctions AS :libfile LANGUAGE 'Python';

-- Step 2: Create functions
CREATE FUNCTION json_demo AS NAME 'json_demo_factory' LIBRARY JsonDemoFunctions;

-- Step 3: Test
SELECT json_demo('{"success": "true", "status": 200, "message": "Hello"}');

-- Step 4: Clean up
DROP LIBRARY JsonDemoFunctions CASCADE;

Thanks Bryan !!