oracle query in python - The return type must be a string, dict, tuple

Question

I'm trying to show the output of a query on the web api endpoint but it isn't working.

The code below is returning TypeError: The view function did not return a valid response. The return type must be a string, dict, tuple, Response instance, or WSGI callable, but it was a int .

I already tried different ways but no luck. What am I missing here?

from flask import Flask, jsonify, request, render_template
from flask_cors import CORS
import cx_Oracle
import os
import json
import logging

app = Flask(__name__)
app.logger.disabled = True
log = logging.getLogger('werkzeug')
log.disabled = True

@app.route('/query')
def query1():

  connection = cx_Oracle.connect(user='superuser', password='mypass1', dsn='moon.my-org.local:1521/db1_sql')
  cursor = connection.cursor()

  cursor.execute("""SELECT * from users""")

  result = cursor.fetchone()
  if result == None:
          return("No results")
          exit
  else:
          while result:
                  return result[0]
                  result = cursor.fetchone()

  cursor.close()
  connection.close()

port = int(os.getenv("PORT"))
app.run(host='0.0.0.0', port=port, debug=True)

Answer 1

If the problem is just that you're returning an integer instead of a string, then it's a simple matter to transform it into a string with str() :

return str(result[0])

However, you have another problem -- that return statement is inside a loop, which means only the very first result will be returned and then the function will exit altogether. The loop won't execute past the first iteration.