Develop Reference

Connect node app and server + post image to server

I have a very basic question about a node application, and a question about HTTP requests. It's the first time I create a node app with server, and I just can't seem to get the different components to work together.
This is my server.js
var express = require('express');
var multer = require('multer');
const request = require('request');
const upload = multer({dest: __dirname + '/uploads/images'});
const app = express();
const PORT = 3000;
app.use(express.static('public'));
app.post('/upload', upload.single('photo'), (req, res) => {
if(req.file) {
res.json(req.file);
}
else throw 'error';
});
app.listen(PORT, () => {
console.log('Listening at ' + PORT );
});
Then I have a file app.js with a motion-detection system. Every time motion is detected, a picture is taken. This all works fine.
Then the picture should be sent to the server. This is what I can't figure out.
I created a function toServer() that should post the detected data to the server
const request = require('request');
function toServer(data) {
const formData = {
// Pass data via Buffers
my_buffer: data,
// Pass optional meta-data with an 'options' object with style: {value: DATA, options: OPTIONS}
// Use case: for some types of streams, you'll need to provide "file"-related information manually.
// See the `form-data` README for more information about options: https://github.com/form-data/form-data
};
request.post({url:'http://localhost:3000/upload', formData: formData}, function optionalCallback(err, httpResponse, body) {
if (err) {
return console.error('Upload failed:', err);
}
console.log('Upload successful! Server responded with:', body);
});
};
Problem 1: when running the server.js on localhost:3000, it doesn't find any of the scripts loaded in index.html nor my app.js.
Problem 2: when running the index.html on live-server, all scripts are found, but i get the error "request is not defined".
I am pretty sure there is some basic node setup thing I'm missing.
The solution for toServer() might be more complicated.
Thanks for your time,
Mustard Shaper

Problem 1:
this could happen because you have not specified to render your index.html.
for example:
res.render('index')
if it's not because of the single quotes in upload.single('photo') try double quotes.
Another possible error could be that you are missing a default display engine setting.
an example: https://www.npmjs.com/package/hbs
Problem 2:
it may be because you are missing the header
var request = require('request');
request.post({
headers: {'content-type' : 'application/x-www-form-urlencoded'},
url: 'http://localhost',
body: "example"
}, function(error, response, body){
console.log(body);
});
See more at https://expressjs.com/

Streaming JSON with Node.js

I have been given a task — I'm trying to make routes/endpoints using just Node to better demostrate what is happening under the covers with Express. But I have to use streams.
I have two routes GET /songs and GET/refresh-songs with the following requirements:
We need the following two endpoints:
GET /songs
GET /refresh-songs
All endpoints should return JSON with the correct headers
/songs should...
stream data from a src/data/songs.json file
not crash the server if that file or directory doesn't exist
bonus points for triggering refresh code in this case
bonus points for compressing the response
/refresh-songs should...
return immediately
it should not hold the response while songs are being refreshed
return a 202 status code with a status JSON response
continue getting songs from iTunes
frontend should have
UI/button to trigger this endpoint
This is what I have so far in my server.js file where my endpoints will live.
const { createServer } = require('http');
const { parse: parseUrl } = require('url');
const { createGzip } = require('zlib');
const { songs, refreshSongs } = require('./songs');
const fs = require('fs');
const stream = fs.createReadStream('./src/data/songs.jso')
const PORT = 4000;
const server = createServer(({ headers, method, url }, res) => {
const baseResHeaders = {
// CORS stuff is gone. :(
'content-type' : 'application/json'
};
// Routing ¯\_(ツ)_ /¯
//
var path = url.parseUrl(url).pathname;
function onRequest(request, response){
response.writeHead(200, 'Content-Type': baseResHeaders['content-type']);
stream.on('data', function(err, data){
if (err) {
response.writeHead(404);
response.write('File not found');
refreshSongs();
} else {
response.write(createGzip(data))
}
response.end()
})
}
switch (path) {
case '/songs':
onRequest()
break;
case '/refresh-songs':
onRequest()
break;
}
server.on('listening', () => {
console.log(`Server running at http://localhost:${PORT}/`);
});
I am wondering if I am wiring the onRequest method I created correctly and if the switch statement is correctly going to intercept those URL's

REST API node.js

I am trying to retrieve data from a REST API in the server side (.js) and display it in my view (.jade)
I was able to get the data but was not able to send it to the view .
This is how my code looks like :
var BugData ='initial data' ;
var https = require('https');
var optionsget = {
rejectUnauthorized: false,
host : 'My host', // here only the domain name
// (no http/https !)
port : 443,
path : 'Mypath', // the rest of the url with parameters if needed
method : 'GET' // do GET
};
console.info('Options prepared:');
console.info(optionsget);
console.info('Do the GET call');
// do the GET request
var reqGet = https.request(optionsget, function(res) {
console.log("statusCode: ", res.statusCode);
res.on('data', function(d) {
console.info('GET result:\n');
BugData =d;
console.log('Show Data : ***** \n' +d);
});
});
reqGet.end();
reqGet.on('error', function(e) {
console.error(e);
});
res.render('index', { ab:BugData});
BugData (was defined before )is the variable i am trying to send to the view but for some reasons it is empty and does not contain the variable 'd'
Does anyone know why or how can i solve this ?
Thanks

There is no need to write that long code.
Be simple, follow these steps:
1) install request package:
npm install --save request
2) outside of router add:
var request = require('request');
process.env.NODE_TLS_REJECT_UNAUTHORIZED = 0;
3) use this code inside router:
request.get({url: 'https://my-host/Mypath'}, function(err, response, body) {
var data = {};
if (err) {
console.error(err);
data.err = err;
}
data.ab = body;
console.log('Data: ', data);
res.render('index', data);
});

Parsing post data in phantomjs

I am working with the POSTMAN extension to chrome and am trying to send a post request to phantomjs I have managed to send a post request to a phantomjs server script by setting postman as in the attached screenshot
My phantomjs script is as follows:
// import the webserver module, and create a server
var server = require('webserver').create();
var port = require('system').env.PORT || 7788;
console.log("Start Application");
console.log("Listen port " + port);
// Create serever and listen port
server.listen(port, function(request, response) {
console.log("request method: ", request.method); // request.method POST or GET
if(request.method == 'POST' ){
console.log("POST params should be next: ");
console.log(request.headers);
code = response.statusCode = 200;
response.write(code);
response.close();
}
});
when I run phantomjs at the command line , here is the output:
$ phantomjs.exe myscript.js
Start Application
Listen port 7788
null
request method: POST
POST params should be next:
[object Object]
POST params: 1=bill&2=dave
So , it does appear to work. My question is now how to parse post body into variables, so I can access it in the rest of the script.

To read post data, you should not use request.headers as it's HTTP headers (encoding, cache, cookies, ...)
As said here, you should use request.post or request.postRaw.
request.post is a json object, so you write it into the console. That's why you get [object Object]. Try to apply a JSON.stringify(request.post) when logging.
As request.post is a json object, you can also directly read properties using indexers (do not forget to add a basic check if the property is not posted)
Here is an updated version of your script
// import the webserver module, and create a server
var server = require('webserver').create();
var port = require('system').env.PORT || 7788;
console.log("Start Application");
console.log("Listen port " + port);
// Create serever and listen port
server.listen(port, function (request, response) {
console.log("request method: ", request.method); // request.method POST or GET
if (request.method == 'POST') {
console.log("POST params should be next: ");
console.log(JSON.stringify(request.post));//dump
console.log(request.post['1']);//key is '1'
console.log(request.post['2']);//key is '2'
code = response.statusCode = 200;
response.write(code);
response.close();
}
});

Processing PLUpload uploads with node.js

I'm attempting to create a server-side upload component in node.js, but I'm having trouble interpreting the information sent from PLUpload. From what I can tell, PLUpload (in HTML5 mode) sends files as binary information, which creates problems for the node.js packages I've been attempting to use so far (node-formidable and node-express), as they expect normal HTML uploads with multipart content types.
For what it's worth, this is the code I've been attempting to use...
var formidable = require('formidable');
var sys = require('sys');
http.createServer( function( req, res ){
console.log('request detected');
if( req.url == '/upload/' ){
console.log('request processing');
var form = new formidable.IncomingForm();
form.parse( req, function( err, fields, files ){
res.writeHead( 200, {
'Access-Control-Allow-Origin': 'http://tksync.com',
'Access-Control-Allow-Methods': 'GET,PUT,POST,DELETE',
'Access-Control-Allow-Headers': '*',
'content-type': 'text/plain'
});
res.write('received upload:\n');
res.end(sys.inspect({
fields: fields,
files: files
}));
});
}
}).listen( 8080 );

I have no problem to use plupload(in HTML5 mode) with node.js with below code:
module.exports.savePhoto= (req, res) ->
if req.url is "/upload" and req.method.toLowerCase() is "post"
console.log 'savePhoto: req.url=', req.url, 'req.method=', req.method
form = new formidable.IncomingForm()
files = []
fields = []
form.uploadDir = config.PATH_upload
form.on("field", (field, value) ->
console.log field, value
fields.push [ field, value ]
).on("file", (field, file) ->
console.log field, file
files.push [ field, file ]
).on "end", ->
console.log "-> upload done: fields=", fields
console.log "received fields:", util.inspect(fields)
console.log "received files:", util.inspect(files)
size = files[0][1].size
pathList = files[0][1].path.split("/")
#console.log 'pathList=', pathList
file = pathList[pathList.length - 1]
console.log "file=" + file
......

I created node-pluploader to handle this, as I found elife's answer didn't work for chunked uploads, as said chunks come in on different requests.
Express-based usage example:
var Pluploader = require('node-pluploader');
var pluploader = new Pluploader({
uploadLimit: 16
});
/*
* Emitted when an entire file has been uploaded.
*
* #param file {Object} An object containing the uploaded file's name, type, buffered data & size
* #param req {Request} The request that carried in the final chunk
*/
pluploader.on('fileUploaded', function(file, req) {
console.log(file);
});
/*
* Emitted when an error occurs
*
* #param error {Error} The error
*/
pluploader.on('error', function(error) {
throw error;
});
// This example assumes you're using Express
app.post('/upload', function(req, res){
pluploader.handleRequest(req, res);
});