text: /**
   * Responds to any HTTP request that provides the below JSON message in the body.
   * # Example input JSON : {"number1": 1, "operand": "mul", "number2": 2 }
   * @param {!Object} req Cloud Function request context.
   * @param {!Object} res Cloud Function response context.
   */
  exports.calculator = function calculator(req, res) {
    
    if (req.body.operand === undefined) {
      res.status(400).send('No operand defined!');
    } else {
      // Everything is okay
      console.log("Received number1",req.body.number1);
      console.log("Received operand",req.body.operand);
      console.log("Received number2",req.body.number2);
  
      var error, result;
      
      if (isNaN(req.body.number1) || isNaN(req.body.number2)) {
          console.error("Invalid Numbers");			// different logging
          error = "Invalid Numbers!";
          res.status(400).send(error);
  
      }
  
      switch(req.body.operand)
      {
          case "+":
          case "add":
              result = req.body.number1 + req.body.number2;
              break;
          case "-":
          case "sub":
              result = req.body.number1 - req.body.number2;
              break;
          case "*":
          case "mul":
              result = req.body.number1 * req.body.number2;
              break;
          case "/":
          case "div":
              if(req.body.number2 === 0){
              	console.error("The divisor cannot be 0");
                  error = "The divisor cannot be 0";
                  res.status(400).send(error);
              }
              else{
                  result = req.body.number1/req.body.number2;
              }
              break;
          default:
              res.status(400).send("Invalid operand");
              break;
      }
      console.log("The Result is: " + result);
  
      res.status(200).send('The result is: ' + result);
    }
  };
  
  