Express-echo server.js

// In this Express exercise, your task is to create an app that responds to GET and POST requests on the / route. The responses will echo a message string from the request.

// GET /
// This route will read the message parameter and send a JSON response containing the echoed message value. The response should have a 200 status.

// An example query string is ?message=hello which would be echoed as {"message": "hello"}. An empty string, ?message=, is valid and should be echoed normally.

// Respond with a 422 status and the JSON {"error": "'message' was not provided"} when no query parameter message exists.

// Respond with a 422 status and the JSON {"error": "'message' was not a string"} when the message was provided, but of a type other than a string.

// POST /
// This route will parse the request body as JSON and echo a response containing the value from the "message" key of the request. The JSON response is in the same format as the GET above: {"message": "some message"}. Set a 200 status on the response to indicate that the request was OK. An empty string ("message": "") is valid and should be echoed.

// Respond with a 422 status when no "message" key exists, or if the message type is other than a string. The JSON errors for these cases are identical to those used in GET.

// For either method, a request is still valid if additional parameters or keys are present in the query or JSON body. You can ignore them and echo message as normal.

// Notes
// Please use the variable name app to implement your server. Don't use app.listen() to start the Express server; the test suite will invoke the route handlers directly on the app object.

// Your solution file is automatically included with the test suite, so no export is necessary.

// Test input strings consist of alphanumeric characters and spaces.

// If you're not familiar with the Express concepts needed to complete this kata, feel free to reference the documentation and other resources as you build your solution.



const express = require('express');
const app = express();

app.use(express.json());

app.get('/', (req, res) => {
  if(req.query.message === undefined) res.status(422).send({ 'error': "'message' was not provided" });
  else if(typeof req.query.message != 'string') res.status(422).send({ 'error': "'message' was not a string" });
  else res.status(200).send({ 'message': req.query.message });  
});

app.post('/', (req, res) => {
  if(req.body.message === undefined) res.status(422).send({ 'error': "'message' was not provided" });
  else if(typeof req.body.message != 'string') res.status(422).send({ 'error': "'message' was not a string" });
  else res.status(200).send({ 'message': req.body.message });
});