Configure the Advanced I/O Function

The Advanced I/O function directory (functions/news_app_function) contains the following files:

• The main.py main function file
• The catalyst-config.json configuration file
• requirements.txt file

Add Code

You will be adding code in the main.py file.

The Advanced I/O function fetches the news item from its source table in the Data Store and forwards it to the client component as a JSON response.

Copy the code and paste it in the main.py in the functions/news_app_function directory.

    

        
main.py
        

            
copy
            

                

            
        
    
    

    

         import logging
from flask import Request, make_response, jsonify
import zcatalyst_sdk

def handler(request: Request):
    #Initializing Catalyst SDK
    app = zcatalyst_sdk.initialize()
    logger = logging.getLogger()
    # GET API that gets the news from the required table
    if request.path == "/fetchData":
        table_name = request.args.get("tablename")
        logger.info("Fetching news from datastore table - "+table_name)
        zcql_instance = app.zcql()
        # Query to fetch news from table
        query = "Select title,url from "+table_name
        #Queries the Catalyst Data Store table and gets the required news
        zcql_result = zcql_instance.execute_query(query)
        return jsonify({"content": zcql_result}), 200
    else:
        # For undefined path error will be thrown
        response = make_response('Unknown path')
        response.status_code = 400
        return response

         
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The Advanced I/O function is now configured. We will discuss the application’s architecture after we configure the client.