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My weather app is throwing type error of temp.. It was console logging the data when I checked but as I enter city Lat and Log it shows type error [duplicate]

I'm trying to get my function to return the http get request, however, whatever I do it seems to get lost in the ?scope?. I'm quit new to Node.js so any help would be appreciated
function getData(){
var http = require('http');
var str = '';
var options = {
host: 'www.random.org',
path: '/integers/?num=1&min=1&max=10&col=1&base=10&format=plain&rnd=new'
};
callback = function(response) {
response.on('data', function (chunk) {
str += chunk;
});
response.on('end', function () {
console.log(str);
});
//return str;
}
var req = http.request(options, callback).end();
// These just return undefined and empty
console.log(req.data);
console.log(str);
}

Of course your logs return undefined : you log before the request is done. The problem isn't scope but asynchronicity.
http.request is asynchronous, that's why it takes a callback as parameter. Do what you have to do in the callback (the one you pass to response.end):
callback = function(response) {
response.on('data', function (chunk) {
str += chunk;
});
response.on('end', function () {
console.log(req.data);
console.log(str);
// your code here if you want to use the results !
});
}
var req = http.request(options, callback).end();

Simple Working Example of Http request using node.
const http = require('https')
httprequest().then((data) => {
const response = {
statusCode: 200,
body: JSON.stringify(data),
};
return response;
});
function httprequest() {
return new Promise((resolve, reject) => {
const options = {
host: 'jsonplaceholder.typicode.com',
path: '/todos',
port: 443,
method: 'GET'
};
const req = http.request(options, (res) => {
if (res.statusCode < 200 || res.statusCode >= 300) {
return reject(new Error('statusCode=' + res.statusCode));
}
var body = [];
res.on('data', function(chunk) {
body.push(chunk);
});
res.on('end', function() {
try {
body = JSON.parse(Buffer.concat(body).toString());
} catch(e) {
reject(e);
}
resolve(body);
});
});
req.on('error', (e) => {
reject(e.message);
});
// send the request
req.end();
});
}

Shorter example using http.get:
require('http').get('http://httpbin.org/ip', (res) => {
res.setEncoding('utf8');
res.on('data', function (body) {
console.log(body);
});
});

from learnyounode:
var http = require('http')
http.get(options, function (response) {
response.setEncoding('utf8')
response.on('data', console.log)
response.on('error', console.error)
})
'options' is the host/path variable

from learnyounode:
var http = require('http')
var bl = require('bl')
http.get(process.argv[2], function (response) {
response.pipe(bl(function (err, data) {
if (err)
return console.error(err)
data = data.toString()
console.log(data)
}))
})

I think it's too late to answer this question but I faced the same problem recently my use case was to call the paginated JSON API and get all the data from each pagination and append it to a single array.
const https = require('https');
const apiUrl = "https://example.com/api/movies/search/?Title=";
let finaldata = [];
let someCallBack = function(data){
finaldata.push(...data);
console.log(finaldata);
};
const getData = function (substr, pageNo=1, someCallBack) {
let actualUrl = apiUrl + `${substr}&page=${pageNo}`;
let mydata = []
https.get(actualUrl, (resp) => {
let data = '';
resp.on('data', (chunk) => {
data += chunk;
});
resp.on('end', async () => {
if (JSON.parse(data).total_pages!==null){
pageNo+=1;
somCallBack(JSON.parse(data).data);
await getData(substr, pageNo, someCallBack);
}
});
}).on("error", (err) => {
console.log("Error: " + err.message);
});
}
getData("spiderman", pageNo=1, someCallBack);
Like #ackuser mentioned we can use other module but In my use case I had to use the node https. Hoping this will help others.

This is my solution, although for sure you can use a lot of modules that give you the object as a promise or similar. Anyway, you were missing another callback
function getData(callbackData){
var http = require('http');
var str = '';
var options = {
host: 'www.random.org',
path: '/integers/?num=1&min=1&max=10&col=1&base=10&format=plain&rnd=new'
};
callback = function(response) {
response.on('data', function (chunk) {
str += chunk;
});
response.on('end', function () {
console.log(str);
callbackData(str);
});
//return str;
}
var req = http.request(options, callback).end();
// These just return undefined and empty
console.log(req.data);
console.log(str);
}
somewhere else
getData(function(data){
// YOUR CODE HERE!!!
})

Make HTTP get request

I am trying to make a HTTP get request, but nothing is being returned as text. Here is my code
const http = require('http');
const ws = require('ws');
const wss = new ws.Server({noServer: true});
var XMLHttpRequest = require('xhr2');
function accept(req, res) {
console.log("got request")
wss.handleUpgrade(req, req.socket, Buffer.alloc(0), function(ws) {
//party name, sockets on party, limit 2
ws.on('message', function (msg) {
var message = JSON.parse(msg.toString())
if(message.type==='add') {
//do later
} else if(message.type==='start') {
httpGetAsync('192.168.26.23', "/startRelay")
} else if(message.type==='stop') {
httpGetAsync('92.168.26.23', "/stopRelay")
} else if(message.type==='status') {
httpGetAsync('92.168.26.23', "/")
}
});
ws.on('close', function () {
console.log('closed')
});
ws.on('error', function(error){
console.log('error - ' + JSON.stringify(error));
});
})
}
function httpGetAsync(theUrl, path) {
var options = {
host: theUrl,
path: path,
method: "GET",
}
callback = async function(response) {
var str = ''
response.on('data', function (chunk) {
str += chunk;
});
response.on('end', function () {
console.log(JSON.parse(str));
});
};
http.request(options, callback).end();
}
http.createServer(accept).listen(3000);
Here is what 192.168.26.23 has in it (if you type it up from my wifi onto google, this is what shows - and this data is what I need to get in a string)
{"success":true,"ms_left":0,"relayStarted":false}

HTTP request callback on Node JS

Hi I am trying to get a response via a http using the callback method. But I get an error saying callback is not a function.
module.exports.ipLookup = function (res, callback) {
var http = require('http');
var str = '';
var options = {
host: 'ip-api.com',
port: 80,
path: '/json/',
method: 'POST'
};
var str= "";
var req = http.request(options, function (res) {
res.on('data', function (body) {
str += body;
});
res.on('end', function () {
callback(str);
});
});
req.end();
return str;
}
What is should to id return the json api response via ip-api.com. If anyone can help me on this it would be greatly appreciated.

In the other file you are loading the function from you need to ensure the callback parameter is used. See snippet below
var Lookup = require('./ip');
Lookup.ipLookup(function (response) {
console.log(response) // check if response is valid
})
You need to change the exported function to only accept one parameter as the first parameter is not used inside function body like so.
module.exports.ipLookup = function (callback) {
var http = require('http');
var str = '';
var options = {
host: 'ip-api.com',
port: 80,
path: '/json/',
method: 'POST'
};
var req = http.request(options, function (res) {
res.on('data', function (body) {
str += body;
});
res.on('end', function () {
return callback(str);
});
});
req.end();
}

Async with http Node.js

I have 2 asynchronous functions on gives me some urls and other one gives me the content I need from the url and one that writes the content I need to an file, but it write to file first and then it gives me the content I need to write, how can I get him to write to file after I get the content I need. Thanks
var http = require('http');
var fs = require('fs');
var list = {};
var k = 0;
function getContent(url){
var options = {
host: 'www.exammple.org',
path: url
}
var request = http.request(options, function (res) {
var data = '';
res.on('data', function (chunk) {
data += chunk;
});
res.on('end', function () {
list[k] = data;
k++;
});
});
request.on('error', function (e) {
console.log(e.message);
});
request.end();
}
var options = {
host: 'www.example2.org',
path: '/mypath'
}
var request = http.request(options, function (res) {
var data = '';
res.on('data', function (chunk) {
data += chunk;
});
res.on('end', function () {
///Here I get some urls from data
data = data.split(";");
for(key in data){
data = data.split('href=\"')[1].split('"')[0];
getContent(data[key]);
}
writeToFile();
}
});
});
request.on('error', function (e) {
console.log(e.message);
});
function writeToFile(){
fs.writeFile("file.txt", JSON.stringify(list), function(err) {
if(err) {
console.log(err);
} else {
console.log("The file was saved");
}
});
}
request.end();

Regex returning all occurences, I only need the first

I can't figure out why this is returning both occurrences of the string /Most recent instantaneous value: ([^ ]+) / I only need the first match.
var http = require("http");
var options = {
host: 'waterdata.usgs.gov',
port: 80,
path: '/ga/nwis/uv?cb_72036=on&cb_00062=on&format=gif_default&period=1&site_no=02334400'
};
function extract (body, cb) {
if(!body)
return;
var matches=body.match(/Most recent instantaneous value: ([^ ]+) /);
if(matches)
cb(matches[1]);
}
http.get(options, function(res) {
res.setEncoding('utf8');
res.on('data', function (chunk) {
extract(chunk, function(v){ console.log(v); });
});
}).on('error', function(e) {
console.log('problem with request: ' + e.message);
});

The 'data' event is being fired many times.
You can fix it by changing the last part to:
http.get(options, function(res) {
var responseText = '';
res.setEncoding('utf8');
res.on('data', function(chunk) {
responseText += chunk;
});
res.on('end', function() {
extract(responseText, console.log);
});
}).on('error', function(e) {
console.log('problem with request: ' + e.message);
});