This is the Input I am providing

{
    "cities" : [
        "kolkata",
        "mumbai",
        "chennai"
    ]
}

and this is the response I am receiving.

{
    "weather": [
        {
            "chennai": "30C"
        },
        {
            "mumbai": "27C"
        },
        {
            "kolkata": "26C"
        }
    ]
}

I want a response somewhat like

{
    "weather" : {
        "kolkata" : "26C",
        "mumbai": "27C",
        "chennai": "30C"
    }
}

My code is as follows.

const express = require('express');
const router = express.Router();
const bodyParser = require('body-parser');
const request = require('request');
const app = express();

const apiKey = 'c6068c4018def9330b01366aed03b08e';

app.use(express.static('public'));
app.use(bodyParser.json());

router.post('/getWeather', function (req, res) {
    let cities = req.body.cities;
    let weatherJson = [];

    for(let i=0; i<cities.length; i  )
    {
        let city = cities[i];
        let url = `http://api.weatherstack.com/current?access_key=${apiKey}&query=${city}`;
        request(url, function (response, body) {
            if (response) {
                return res.json({ error: response });
            }
            let weather = JSON.parse(body.body);
            if (weather.current == undefined) {
                return res.json({ error: "somethin went wrong!" });
            }
            let weatherText = `${weather.current.temperature}C`;
            weatherJson.push({ [city] : weatherText });
            if(weatherJson.length == cities.length) {
                console.log("here");
                res.json({"weather": weatherJson});
            }
        });
    }
});

app.use('/', router);

app.listen(3000, function () {
    console.log('Example app listening on port 3000!')
});

I have tried adding as hashmap, adding in array format then using stringify at the response point, but nothing seems to work. I just want to convert the format of the response to the desirable one with as minimalistic change in the code as possible. Please help.

CodePudding user response：

You have a few issues, first off you're storing weatherJson (response) as an array when you say you want it to be a map.

here's how I would implement this:

router.post("/getWeather", async function (req, res) {
  let cities = req.body.cities;
  let weatherJson = {};

  for (let i = 0; i < cities.length; i  ) {
    let city = cities[i];
    let url = `http://api.weatherstack.com/current?access_key=${apiKey}&query=${city}`;
    try {
      const response = await fetch(url);
      let weather = JSON.parse(response.body);
      if (weather.current == undefined) {
        return res.json({ error: "somethin went wrong!" });
      }
      let weatherText = `${weather.current.temperature}C`;
      weatherJson[city] = weatherText;
    } catch (err) {
      return res.json({ error: err });
    }
  }

  res.json({ weather: weatherJson });
});

You should use node-fetch instead of request which is obsolete. It does the same thing but much cleaner with promises instead of callbacks.

CodePudding user response：

try creating an object instead of an array.

const express = require('express');
const router = express.Router();
const bodyParser = require('body-parser');
const request = require('request');
const app = express();

const apiKey = 'c6068c4018def9330b01366aed03b08e';

app.use(express.static('public'));
app.use(bodyParser.json());

router.post('/getWeather', function (req, res) {
    let cities = req.body.cities;
    let weatherJson = {};

    for(let i=0; i<cities.length; i  )
    {
        let city = cities[i];
        let url = `http://api.weatherstack.com/current?access_key=${apiKey}&query=${city}`;
        request(url, function (response, body) {
            if (response) {
                return res.json({ error: response });
            }
            let weather = JSON.parse(body.body);
            if (weather.current == undefined) {
                return res.json({ error: "somethin went wrong!" });
            }
            let weatherText = `${weather.current.temperature}C`;
            weatherJson[city]=weatherText;
            if(Object.keys(weatherJson).length == cities.length) {
                console.log("here");
                res.json({"weather": weatherJson});
            }
        });
    }
});

app.use('/', router);

app.listen(3000, function () {
    console.log('Example app listening on port 3000!')
});