NodeJS - Third party Api call from app.js

Question

I need to call 3rd party api from backend in NodeJS and return the data to ajax call in frontend

Below is my code:

router.post('/get_data', function(request, response){
var city_name = request.body.city_name;
if(city_name in city_name_done){

}
else {
    city_name_done.push(city_name);
    console.log('city_name: ' + city_name);
    var options = {
        host : 'api.openweathermap.org',
        path : '/data/2.5/forecast/daily?q=' + city_name + '&mode=json&units=metric&cnt=14&appid=75e843de569fb57a783c2e73fd9a7bb5',
        method : 'GET'
    }
    var maybe = '';
    console.log('till here')
    var req = http.request(options, function(res){
        var body = "";
        res.on('data', function(data) {
            console.log('data came');
            body += data;
        });
        res.on('end', function() {
            console.log('ended too');
            maybe = JSON.parse(body);
            console.log(maybe.city);
        });
    });
    console.log('here too man');
    req.on('error', function(e) {
        console.log('Problem with request: ' + e.message);
    });
    response.send(maybe);
}
});

I am able to get the city_name parameter from ajax post request from frontend side however I get 500 internal server error everytime I execute the post request

PS: Pardon my English and even the level of the question as I am an absolute beginner in NodeJS

Answer 1

You are returning response from outside of function call that gets data from 3rd party api. You need to return response from res.on('end' section. It is because api call is asynchronous and we have to wait for response to come.

res.on('end', function() {
     console.log('ended too');
     maybe = JSON.parse(body);
     console.log(maybe.city);
     response.send(maybe);
});

Complete code is

    router.post('/get_data', function(request, response){
var city_name = request.body.city_name;
if(city_name in city_name_done){

}
else {
    city_name_done.push(city_name);
    console.log('city_name: ' + city_name);
    var options = {
        host : 'api.openweathermap.org',
        path : '/data/2.5/forecast/daily?q=' + city_name + '&mode=json&units=metric&cnt=14&appid=75e843de569fb57a783c2e73fd9a7bb5',
        method : 'GET'
    }
    var maybe = '';
    console.log('till here')
    var req = http.request(options, function(res){
        var body = "";
        res.on('data', function(data) {
            console.log('data came');
            body += data;
        });
        res.on('end', function() {
            console.log('ended too');
            maybe = JSON.parse(body);
            console.log(maybe.city);
            response.send(maybe);
        });
    });
    console.log('here too man');
    req.on('error', function(e) {
        console.log('Problem with request: ' + e.message);
    });
    res.end();
}
});