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Implementing CoAP protocol on node.js

Do you know any guides or tutorials about implementing CoAP protocol connection on node.js? I have to implement simple server and client application. I've checked all the resources I've found, including of course their documentation:
https://github.com/mcollina/node-coap
but it is still unclear for me.
Thank you for any help.
EDIT:
If this is implementation of server, how should look client like?
var coap = require('coap')
, server = coap.createServer()
server.on('request', function(req, res) {
res.end('Hello ' + req.url.split('/')[1] + '\n')
})
// the default CoAP port is 5683
server.listen(function() {
var req = coap.request('coap://localhost/Matteo')
req.on('response', function(res) {
res.pipe(process.stdout)
res.on('end', function() {
process.exit(0)
})
})
req.end()
})

or like this , an example for coap client
const coap = require('coap'),
bl = require('bl');
//construct coap request
var req = coap.request({
observe: false,
host: '192.168.0.93',
pathname: '/',
port: 5683,
method: 'get',
confirmable: 'true',
retrySend: 'true',
//query:'',
options: {
// "Content-Format": 'application/json'
}
})
//put payload into request
var payload = {
username: 'aniu',
}
req.write(JSON.stringify(payload));
//waiting for coap server send con response
req.on('response', function(res) {
//print response code, headers,options,method
console.log('response code', res.code);
if (res.code !== '2.05') return process.exit(1);
//get response/payload from coap server, server sends json format
res.pipe(bl(function(err, data) {
//parse data into string
var json = JSON.parse(data);
console.log("string:", json);
// JSON.stringify(json));
}))
});
req.end();

It should be like this:
const coap = require('coap')
req = coap.request('coap://localhost')
console.log("Client Request...")
req.on('response' , function(res){
res.pipe(process.stdout)
})
req.end()
Source: https://github.com/mcollina/node-coap/blob/master/examples/client.js

Http GET Request from NodeJS to external API with http.get()

I am trying to do an HTTP GET request to an external API with NodeJS (using Express), but I am not getting any data back. My code is the nextone:
import * as http from "http";
const options = {
host: "EXAMPLE.COM",
path: "/MY/PATH",
headers: {
"Content-Type": "application/json",
"Authorization": "Basic XXXXXXXXXXXXXXXXXX"
}
};
const req = http.get(options, function(res) {
console.log("statusCode: " + res.statusCode);
res.on("data", function (chunk) {
console.log("BODY: " + chunk);
});
});
But the response I get is:
statusCode : 302 and BODY is empty.
The external API works properly (I have tried doing a http GET Request with INSOMNIA and returns data)
The request I am doing NEEDS an Authorization Token
What am I doing wrong? or what can I do to get the data back?
Cheers

You are just throwing data to console.log and not responding to request.
You did not mention if what http server you are using with node. In case you are using express.js (most common one) you should have something like:
const express = require("express");
const app = express();
const port = 3003;
const http = require("http");
// your webserver url localhost:3003/fetch-something
app.get("/fetch-something", (req, res) => {
const options = {
host: "EXAMPLE.COM",
path: "/MY/PATH",
headers: {
"Content-Type": "application/json",
Authorization: "Basic XXXXXXXXXXXXXXXXXX"
}
};
const httpReq = http.get(options, function(httpRes) {
//output status code to your console
console.log("statusCode: " + httpRes.statusCode);
httpRes.on("data", function(chunk) {
// still nothing happens on client - this will also just print to server console
console.log("data", chunk);
// return some data for requested route
return res.send(chunk);
});
});
});
app.listen(port, () => console.log(`Example app listening on port ${port}!`));

Invalid response using https module in javaScript to fetch a public facebook profile

I am using node's https module to fetch my public profile from facebook. But i am getting 302 status code in response. Following is the code i am using:
var https = require('https');
var options = {
hostname: 'www.facebook.com',
path: '/suri.nik',
method: 'GET'
};
var results = '';
var req = https.request(options, function (res) {
console.log('STATUS CODE : ' + res.statusCode);
res.on('data', function (chunk) {
results = results + chunk;
});
res.on('end', function () {
console.log(results);
});
res.on('error', function () {
console.log('error here');
});
});
req.on('error', function (e) {
console.log('error in ur request: ' + e);
});
req.end();
I am getting STATUS CODE : 302, i should be getting status code : 200 with valid html in response of my profile. I am able to fetch the public profile from my browser or postman using the same link(www.facebook.com/suri.nik) Where lies the issue? is it the way i am making my request?

communicate between a server and a client with node.js

I have a node.js Server:-
// *********** Server that receives orders ************ //
// to use features of the http protocol. //
var http = require('http');
// initialize to empty string. //
var req = "";
// create the server that will receive an order Request. //
var server = http.createServer(function(req,res) {
res.writeHead(200, {'content-type': 'text/plain'});
// when data is successfully received, a success message is displayed. //
res.on('data', function(data){
req += data; // received data is appended. //
console.log("We have received your request successfully.");
});
});
// An error message is displayed - error event. //
server.on('error', function(e){
console.log("There is a problem with the request:\n" + e.message);
});
// server listens at the following port and localhost (IP). //
server.listen(8000, '127.0.0.1');
and then I have a node.js Client:-
var http = require("http");
var querystring = require("querystring");
var postOrder = querystring.stringify({
'msg': 'Hello World!'
});
var options = {
hostname: '127.0.0.1',
port: 8000,
path:'/order',
method:'POST',
headers:{
'Content-Type' :'application/x-www-form-urlencoded',
'Content-Length' : postOrder.length
}
};
var req = http.request(options, function(res) {
console.log('STATUS: ' + res.statusCode);
console.log('HEADERS: ' + JSON.stringify(res.headers));
res.setEncoding('utf8');
res.on('data', function (chunk) {
console.log('BODY: ' + chunk);
});
});
req.on('error', function(e) {
console.log('problem with request: ' + e.message);
});
// write data to request body
req.write(postOrder);
req.end();
I am trying to figure out how I can make the client post its order to the server and get a response back from the server...either a success message or an error message...using command line.
currently I run the server on cmd line $ node server.js
and then a run the client $ node client.js
but i get no responses.

I think that have problems from the server:
The Server must be:
http.createServer(function(req, res) {
if (req.method == 'GET') {
} else if (req.method == 'POST') {
var body = '';
req.on('data', function(data) {
body += data;
});
req.on('end', function() {
console.log("We have received your request successfully.");
});
}
res.end("ok");
})

Steps to send a https request to a rest service in Node js

What are the steps to send a https request in node js to a rest service?
I have an api exposed like (Original link not working...)
How to pass the request and what are the options I need to give for this API like
host, port, path and method?

just use the core https module with the https.request function. Example for a POST request (GET would be similar):
var https = require('https');
var options = {
host: 'www.google.com',
port: 443,
path: '/upload',
method: 'POST'
};
var req = https.request(options, function(res) {
console.log('STATUS: ' + res.statusCode);
console.log('HEADERS: ' + JSON.stringify(res.headers));
res.setEncoding('utf8');
res.on('data', function (chunk) {
console.log('BODY: ' + chunk);
});
});
req.on('error', function(e) {
console.log('problem with request: ' + e.message);
});
// write data to request body
req.write('data\n');
req.write('data\n');
req.end();

The easiest way is to use the request module.
request('https://example.com/url?a=b', function (error, response, body) {
if (!error && response.statusCode == 200) {
console.log(body);
}
});

Note if you are using https.request do not directly use the body from res.on('data',... This will fail if you have a large data coming in chunks. So you need to concatenate all the data and then process the response in res.on('end'. Example -
var options = {
hostname: "www.google.com",
port: 443,
path: "/upload",
method: 'POST',
headers: {
'Content-Type': 'application/json',
'Content-Length': Buffer.byteLength(post_data)
}
};
//change to http for local testing
var req = https.request(options, function (res) {
res.setEncoding('utf8');
var body = '';
res.on('data', function (chunk) {
body = body + chunk;
});
res.on('end',function(){
console.log("Body :" + body);
if (res.statusCode !== 200) {
callback("Api call failed with response code " + res.statusCode);
} else {
callback(null);
}
});
});
req.on('error', function (e) {
console.log("Error : " + e.message);
callback(e);
});
// write data to request body
req.write(post_data);
req.end();

Using the request module solved the issue.
// Include the request library for Node.js
var request = require('request');
// Basic Authentication credentials
var username = "vinod";
var password = "12345";
var authenticationHeader = "Basic " + new Buffer(username + ":" + password).toString("base64");
request(
{
url : "https://133-70-97-54-43.sample.com/feedSample/Query_Status_View/Query_Status/Output1?STATUS=Joined%20school",
headers : { "Authorization" : authenticationHeader }
},
function (error, response, body) {
console.log(body); } );

Since there isn't any example with a ´GET´ method here is one.
The catch is that the path in the options Object should be set to '/' in order to send the request correctly
const https = require('https')
const options = {
hostname: 'www.google.com',
port: 443,
path: '/',
method: 'GET',
headers: {
'Accept': 'plain/html',
'Accept-Encoding': '*',
}
}
const req = https.request(options, res => {
console.log(`statusCode: ${res.statusCode}`);
console.log('headers:', res.headers);
res.on('data', d => {
process.stdout.write(d)
})
})
req.on('error', error => {
console.error(`Error on Get Request --> ${error}`)
})
req.end()

The example using 'GET' method is good but it can also be used with constant variables in TypeScript/Node.js setup. If that's the case, the functions on('error') and end() have to be defined outside of the https.request function.
const https = require('https')
const options = {
hostname: 'www.google.com',
port: 443,
path: '/',
method: 'GET',
headers: {
'Accept': 'plain/html',
'Accept-Encoding': '*',
}
}
const request = https.request(options, res => {
const callback = (data: string) => {
process.stdout.write(`response data: ${data}`);
}
res.on('data', callback)
})
request.on('error', error => {
console.error(`Error on Get Request --> ${error}`)
})
request.end()