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Node js get image from web and convert it into an array of byte values

What other libraries i can use with request so I can convert it to an array of bytes?
var request = require('request');
request('https://randomuser.me/api/portraits/men/81.jpg', function (error, response, body) {
if (!error && response.statusCode == 200) {
}
})

ImageMagic, which has several 3rd party JS SDKs, would work.

NPM Request not get html from thai url. (Web Scraping)

This code will not show html in console it show error
var request = require('request');
var thai_url = "http://pantip.com/tag/Honda_(มอเตอร์ไซค์)";
request(thai_url, function (error, response, html) {
if (!error && response.statusCode === 200) {
console.log(html);
} else {
console.log("Error");
}
});
But I change thai_url from มอเตอร์ไซค์ to %E0%B8%A1%E0%B8%AD%E0%B9%80%E0%B8%95%E0%B8%AD%E0%B8%A3%E0%B9%8C%E0%B9%84%E0%B8%8B%E0%B8%84%E0%B9%8C
Like This
var request = require('request');
var thai_url = "http://pantip.com/tag/Honda_(%E0%B8%A1%E0%B8%AD%E0%B9%80%E0%B8%95%E0%B8%AD%E0%B8%A3%E0%B9%8C%E0%B9%84%E0%B8%8B%E0%B8%84%E0%B9%8C)";
request(thai_url, function (error, response, html) {
if (!error && response.statusCode === 200) {
console.log(html);
} else {
console.log("Error");
}
});
The second code working right. Can I change มอเตอไซค์ to %E0%B8%A1%E0%B8...(more)? Or If it's possible, How am I doing for http://pantip.com/tag/Honda_(มอเตอร์ไซค์) working with npm request ? Thank you for any help.

First one is working fine. Just log the error instead of "error" string.
Make sure your IDE supports utf character. otherwise on saving it might be changing it. That why you might get error.

Update. Now I can solve this problem by this
var thai_url = encodeURI("http://pantip.com/tag/Honda_(มอเตอร์ไซค์)");
Use encodeURI. http://www.javascripter.net/faq/escape.htm

Static HTTP File Server in NodeJs: Sometimes external .js and .css files load properly, sometimes they don't?

Edit: I know using express or whatever would be easier, but this is all a learning exercise, so sorry if this is all massively convoluted, haha!
Edit 2: It appears (after adding a few console logs for debugging) that it seems the problem has something to do with the fact that when the browser makes one request to the server (say, for style.css), it makes another request (e.g. for login-fail.js) before completing the response for the first request. It seems these multiple requests from the browser cause some sort of problem, each subsequent request preventing the previous from completing. Yikes, I need help.
Edit 3: After some debugging, it appears that the pathname variable does not change its value upon each request. For some reason, pathname's value persists over each request and this makes every request's response the same - stranger still, the value for uri changes over each request (and the uri is what gives the pathname its value...) still trying to find out why this bizarre behaviour is happening.
So I've been having this problem when the server makes requests for external .js and .css files linked to specific .html files. The responses are always inconsistent. For instance, sometimes the code will run perfectly, other times the css will load and not the js, sometimes both, sometimes neither. I am not able to determine whether this is because my code is synchronous, or for some other reason. Here is my code:
Server.js
//Module requires
var http = require("http"),
fs = require("fs"),
path = require('path'),
url = require('url'),
invoke = require("./invoke");
//Object "MIMETYPES"
//Maps relationships between file extensions and their respective MIME Content-Types
var MIMETYPES = {
".html": "text/html",
".jpeg": "image/jpeg",
".jpg": "image/jpeg",
".png": "image/png",
".js": "text/javascript",
".css": "text/css"
};
//Object "invokeOptions"
//Options passed to Invoke() function for POST requests
var invokeOptions = {
postData : "",
uri : ""
}
var PORT = 8888;
//HTTP Server Begin
http.createServer(function(req, res) {
var uri = url.parse(req.url).pathname;
pathname = path.resolve(__dirname, "..") + uri;
console.log("Recieved " + req.method + " request for : " + uri);
invokeOptions.uri = uri;
//GET requests wrapper
if (req.method == "GET"){
//Invoke() function handler for GET requests
if (path.extname(pathname) == ""){
invoke.invoke(invokeOptions, req, res);
return;
}
//Static file server for GET requests
fs.exists(pathname, function(exists) {
if(!exists) {
console.log("Requested file \'" + pathname + "\' doesn't exist.");
res.writeHead(404, {'Content-Type': 'text/plain'});
res.write('404 Not Found\n');
res.end();
return;
}
var contentType = MIMETYPES[path.extname(pathname)];
res.writeHead(200, {"Content-Type" : contentType});
console.log("Current URI: " + uri + " has content type: " + contentType);
fs.createReadStream(pathname).pipe(res);
return;
});
}
//POST requests wrapper
if (req.method == "POST"){
var postData = "";
req.on("data", function(postPacket) {
postData += postPacket;
});
req.on("end", function() {
invokeOptions.postData = postData;
invoke.invoke(invokeOptions, req, res);
return;
});
}
}).listen(PORT);
console.log ("Server listening on port: " + PORT);
Invoke.js - This handles requests for non-files, that is requests for functions on the server
var fs = require("fs"),
querystring = require("querystring"),
path = require("path");
function invoke (options, req, res){
process.stdout.write("Invoking function --> ");
if (options.uri == "/"){
console.log("Index");
res.writeHead(200, {"Content-Type" : "text/html"});
fs.createReadStream("../index.html").pipe(res);
return;
}
if (options.uri == "/login"){
console.log("Login");
fs.readFile(path.resolve("../users.json"), "UTF-8", function(err, data){
if (err) throw err;
var json = JSON.parse(data);
var user = querystring.parse(options.postData).username,
password = querystring.parse(options.postData).password;
console.log("Submitted Username: " + user + "\nSubmitted Password: " + password);
if (json.users[0].username == user && json.users[0].password == password){
res.writeHead(200, {"Content-Type" : "text/html"});
fs.createReadStream("../app.html").pipe(res);
return;
}
else {
res.writeHead(300, {"Content-Type" : "text/html"});
fs.createReadStream("../login-fail.html").pipe(res);
return;
}
});
}
else {
console.log("Error! Bad request.");
res.writeHead(400, {"Content-Type" : "text/plain"});
res.end("Error 400: Bad Request. \nThere is no function corresponding to that request.");
}
}
exports.invoke = invoke;
Login-fail.js - This is the code that hardly ever loads
$(document).ready(function() {
var current = 3;
var countdown = $(".countdown");
function down (){
current--;
if (current != 0){
countdown.text(current);
}
else {
clearInterval(interval);
window.location.replace("./");
}
}
var interval = setInterval(down, 1000);
});
Basically, the index.html file is a form which accepts a username and password, compares the submitted POST data to a json file, and if it matches the hashes in the json file it requests app.html, otherwise it requests login-fail.html. When the login-html file is called, it has linked to it css and js which when requested hardly ever run!
Also, I thought it should be noted that the console.logs for "content-type" when requesting the css is 'text/javascript' when it doesn't work. Any help would be massively appreciated!

Holy crap.
Pathname wasn't being declared as a variable each request, because I used a ; instead of a ,
I'll go die now ladies and gents.

The relative paths you're using in your login-fail.html are probably not resolving correctly because the URL path doesn't change (/login), so the browser is looking for /login/css/style.css and /login/js/login-fail.js. Try modifying your login-fail.html to use absolute paths instead of relative paths.

Node.js mikeal/request module - Garbled non-utf8 website (Shift_JIS)

I am trying to access a non utf-8 website using request module. Response is garbled for this request.
var request = require('request');
request('http://www.alc.co.jp/', function (error, response, body) {
if (!error && response.statusCode == 200) {
console.log(body) // Print the web page.
}
});
Even after setting the encoding option to Shift_JIS I am seeing garbled Japanese text.

You need to do the conversion yourself. The example code below uses node-iconv.
var Iconv = require('iconv').Iconv;
var request = require('request');
request({
uri: 'http://www.jalan.net/',
encoding: null,
}, function (error, response, body) {
if (!error && response.statusCode == 200) {
body = new Iconv('shift_jis', 'utf-8').convert(body).toString();
console.log(body); // Print the web page.
}
});
The encoding: null parameter asks request not to convert the Buffer (a byte array) into String yet.
We pass this buffer to Iconv for converting into another Buffer of UTF-8 encoding.
Now this Buffer is good for being converted into a String.
(BTW, http://www.alc.co.jp has switched to UTF-8, so I substituted with another site.)

Problem receiving response from node server using ajax post request

I have written a http server using node js
var sys = require("sys"),
http = require("http"),
url = require("url"),
path = require("path"),
fs = require("fs");
http.createServer(function(request, res) {
var parsed_url = url.parse(request.url);
var uri = parsed_url.pathname;
if(uri === "/test"){
res.writeHead(200, {'Content-Type': 'text/javascript'});
request.addListener('data', function (chunk) {
var data = eval("(" + chunk + ")");
console.log(data[0].id);
})
request.addListener('end', function() {
console.log('end triggered');
res.write("Post data");
res.end();
});
}
}).listen(8080);
and i am trying to send back response of ajax request but i am unable to receive any response. Here is the code for ajax request ,
var myhttp = new XMLHttpRequest();
var url = "http://localhost:8080/test";
var data = [{"a":"1"},{"b":"2"},{"c":"3"}];
var dataJson = JSON.stringify(data);
myhttp.open('POST', url, true);
myhttp.send(dataJson);
myhttp.onreadystatechange = function() {
if ((myhttp.readyState == 4) && (myhttp.status == 200)){
alert(myhttp.responseText);
}
else if ((myhttp.readyState == 4) && (myhttp.status != 200))
{
console.log("Error in Connection");
}
Can anyone help me what i am doing wrong ...
Thanks
Vinay

Your code is almost right but on your code sample you have
console.log(data[0].id)
the data object has no property id so if you only have
console.log(data[0])
there you have a response like
{ a: '1' }
therefore you can access the property a by doing
console.log(data[0].a);
UPDATED Updated with a full example
One more thing is that you are using eval and node comes with JSON.parse bundle with it so the snippet below is how i made it work
File: app.js
var sys = require("sys"),
http = require("http"),
url = require("url"),
path = require("path"),
fs = require("fs");
http.createServer(function(request, res) {
var parsed_url = url.parse(request.url);
var uri = parsed_url.pathname;
if(uri === "/test"){
res.writeHead(200, {'Content-Type': 'text/javascript'});
request.addListener('data', function (chunk) {
// removed this - eval("(" + chunk + ")");
var data = JSON.parse(chunk);
console.log(data[0].a);
})
request.addListener('end', function() {
console.log('end triggered');
res.write("Post data");
res.end();
});
} else if(uri === "/") {
fs.readFile("./index.html",function(err, data){
if(err) throw err;
res.writeHead(200, {'Content-Type': 'text/html'});
res.end(data);
});
}
}).listen(8080);
On the same directory create a file index.html with the following:
<html>
<head>
<script type="text/javascript" charset="utf-8">
var myhttp = new XMLHttpRequest();
var url = "http://localhost:8080/test";
var data = [{"a":"1"},{"b":"2"},{"c":"3"}];
var dataJson = JSON.stringify(data);
myhttp.open('POST', url, true);
myhttp.send(dataJson);
myhttp.onreadystatechange = function() {
if ((myhttp.readyState == 4) && (myhttp.status == 200)){
alert(myhttp.responseText);
}
else if ((myhttp.readyState == 4) && (myhttp.status != 200))
{
console.log("Error in Connection");
}
}
</script>
</head>
<body>
</body>
</html>
That is a complete working example of what you want.
With regards to the same origin policy issues you were having is mainly due to the fact that you cant POST data between 2 different domains via ajax unless you use some tricks with iframes but that is another story.
Also i think is good for anyone to understand the backbone of a technology before moving into frameworks so fair play to you.
good luck

You have to read the data in a different way. Posted data arrives on a node server in chunks (the 'data' event), that have to be collected until the 'end' event fires. Inside this event, you are able to access your payload.
var body = '';
request.addListener('data', function (chunk) {
body += chunk;
});
request.addListener('end', function() {
console.log(body);
res.write('post data: ' + body);
});
Additionaly, there seem to be some issues with your client-side code (especially concerning the status-code checks), but i can't really help you with those as i always work with frameworks like jQuery to manage async requests.
If you want to build reliable node.js servers for web use, i highly recommend the high-performance HTTP-Framework Express. It takes away alot of the pain when developing a web-based server application in node and is maintained actively.