I want to send the filepath of a file on my server to the client in order to play it using a media player. How can I retrieve that string on the client side in order to concatenate it in the src attribute of a <video element without using sockets?
Server snippet:
res.set('content-type', 'text/plain');
res.send('/files/download.mp4');
This is how you make a request to the server without any frameworks. "/path_to_page" is the route you set to the page that is supposed to process the request.
var xhr = new XMLHttpRequest();
xhr.open('GET', '/path_to_page', true);
xhr.onload = function(e) {
if (this.status == 200) {
console.log(this.responseText); // output will be "/files/download.mp4"
}
};
xhr.send();
}
You might also want to send some params.
var formdata = new FormData();
formdata.append("param_name", "value");
So you might for instance want to send the filename or such.
You just need to change 2 lines from the first code snippet. One would be
xhr.open('POST', '/path_to_page', true); // set to post to send the params
xhr.send(formdata); // send the params
To get the params on the server, if you are using express, they are in req.body.param_name
Which framework are you using??
You can declare base path of your project directory in ajax and the followed by your file.
jQuery.ajax({
type: "GET",
url: "/files/download.mp4",
});
Since you are using express (on node), you could use socket.io:
Server:
var io = require('socket.io').listen(80),
fs = require('fs');
io.sockets.on('connection', function (socket) {
socket.on('download', function(req) {
fs.readFile(req.path, function (err, data) {
if (err) throw err;
socket.emit('video', { video: data });
});
});
});
Client:
<script src="/socket.io/socket.io.js"></script>
<script>
var socket = io.connect('http://localhost');
...
// request a download
socket.emit('download', { path: '/files/download.mp4' });
// receive a download
socket.on('video', function (data) {
// do sth with data.video;
});
...
</script>
Edit: didnt notice you didnt want to use sockets. Still it is a viable solution.
Related
So we get a file (an image file) in the front-end like so:
//html
<input type="file" ng-change="onFileChange">
//javascript
$scope.onFileChange = function (e) {
e.preventDefault();
let file = e.target.files[0];
// I presume this is just a binary file
// I want to HTTP Post this file to a server
// without using form-data
};
What I want to know is - is there a way to POST this file to a server, without including the file as form-data? The problem is that the server I am send a HTTP POST request to, doesn't really know how to store form-data when it receives a request.
I believe this is the right way to do it, but I am not sure.
fetch('www.example.net', { // Your POST endpoint
method: 'POST',
headers: {
"Content-Type": "image/jpeg"
},
body: e.target.files[0] // the file
})
.then(
response => response.json() // if the response is a JSON object
)
You can directly attach the file to the request body. Artifactory doesn't support form uploads (and it doesn't look like they plan to)
You'll still need to proxy the request somehow to avoid CORS issues, and if you're using user credentials, you should be cautious in how you treat them. Also, you could use a library like http-proxy-middleware to avoid having to write/test/maintain the proxy logic.
<input id="file-upload" type="file" />
<script>
function upload(data) {
var file = document.getElementById('file-upload').files[0];
var xhr = new XMLHttpRequest();
xhr.open('PUT', 'https://example.com/artifactory-proxy-avoiding-cors');
xhr.send(file);
}
</script>
Our front-end could not HTTP POST directly to the JFrog/Artifactory server. So we ended up using a Node.js server as a proxy, which is not very ideal.
Front-end:
// in an AngularJS controller:
$scope.onAcqImageFileChange = function (e) {
e.preventDefault();
let file = e.target.files[0];
$scope.acqImageFile = file;
};
// in an AngularJS service
createNewAcqImage: function(options) {
let file = options.file;
return $http({
method: 'POST',
url: '/proxy/image',
data: file,
headers: {
'Content-Type': 'image/jpeg'
}
})
},
Back-end:
const express = require('express');
const router = express.Router();
router.post('/image', function (req, res, next) {
const filename = uuid.v4();
const proxy = http.request({
method: 'PUT',
hostname: 'engci-maven.nabisco.com',
path: `/artifactory/cdt-repo/folder/${filename}`,
headers: {
'Authorization': 'Basic ' + Buffer.from('cdt-deployer:foobar').toString('base64'),
}
}, function(resp){
resp.pipe(res).once('error', next);
});
req.pipe(proxy).once('error', next);
});
module.exports = router;
not that we had to use a PUT request to send an image to Artifactory, not POST, something to do with Artifactory (the engci-maven.nabisco.com server is an Artifactory server). As I recall, I got CORS issues when trying to post directly from our front-end to the other server, so we had to use our server as a proxy, which is something I'd rather avoid, but oh well for now.
Here is my code:
var socket = require('socket.io-client')('http://127.0.0.1:3000/printers', {
query: "shop=" + "123456",
transports: ["websocket"]
});
If I delete query, I can connect to socket. Where am I wrong?
There doesn't seem to be anything wrong with your client-side code. I can connect by copying and pasting your code.
I suspect the problem is within your server-side code. Here is an example I am using with your client-side code:
var http = require('http');
var io = require('socket.io');
var server = http.createServer(function(req,res){
res.writeHead(200);
res.end('Hello, World!\n');
});
server.listen(80);
var socket = io.listen(server);
socket.use(function(socket, next){
console.log("Query: ", socket.handshake.query);
if (socket.handshake.query.shop == '123456') {
next();
}
next(new Error('You cannot use that shop'));
});
socket.on('connection', function(client) {
console.log('New Connection');
});
I'm able to obtain the query data in the 'socket.use' function. If I don't call the next() function, the client will never get the message that the server has received the response and is connected.
I recommend checking out the example used in this thread.
Is it is possible to send image through meteor call to the API?
Client js
var r = {image : image};
Meteor.apply('callToServer', r, function(error, result){
console.log(result);
});
Server js
Meteor.methods({
uploadAndSaveToDB: function(data){
var result = Meteor.http.post(apiUrl, {
params: { image : data['image']}
});
var result = JSON.parse(result.content);
return result;
},
});
If your question is about how to get the image data and send it to your api, it depends on a couple factors:
How are you getting the image's data in the first place from your app (a submission form, a URL, some drawing library...)
In what format does the API you are calling expects the image data to be sent (URL, raw data, encrypted...)
If you are simply asking if it is doable, then yes, definitely. You will just need to add the http package for this:
meteor add http
You can then make requests to your api pretty much like you wrote it. Just make sure to give the right name to your method call (also use call and not apply if you are not submitting an array of arguments):
Client js
var r = {image : image};
Meteor.call('uploadAndSaveToDB', r, function(error, result){
console.log(result);
});
Server js
Meteor.methods({
uploadAndSaveToDB: function(data){
var result = HTTP.post(apiUrl, {
params: { image : data['image']}
});
var result = JSON.parse(result.content);
return result;
},
});
I have the followign JavaScript code:
function upload(blob) {
var xhr = new XMLHttpRequest();
var url = "test.cfm";
xhr.onload=function(e) {
if(this.readyState === 4) {
console.log("Server returned: ",e.target.responseText);
}
};
var fd=new FormData();
fd.append("randomname",blob);
xhr.open("POST",url,true);
xhr.send(fd); }
How can I catch it on server side by ColdFusion and Save blob object to File?
Can someone please some code sample. Thx.
PS. I am pretty new in CF.
Since you are using formdata, you can access the form variable with ajax, just like you would with normal http requests.
#form.randomname#
#form['randomname']#
So you could save the content in a file with
<cfscript>
fileWrite( 'c:\myfile.txt', form.randomname );
</cfscript>
I was in the middle of teaching myself some Ajax, and this lesson required building a simple file upload form locally. I'm running XAMPP on windows 7, with a virtual host set up for http://test. The solution in the book was to use node and an almost unknown package called "multipart" which was supposed to parse the form data but was crapping out on me.
I looked for the best package for the job, and that seems to be formidable. It does the trick and my file will upload locally and I get all the details back through Ajax. BUT, it won't play nice with the simple JS code from the book which was to display the upload progress in a progress element. SO, I looked around and people suggested using socket.io to emit the progress info back to the client page.
I've managed to get formidable working locally, and I've managed to get socket.io working with some basic tutorials. Now, I can't for the life of me get them to work together. I can't even get a simple console log message to be sent back to my page from socket.io while formidable does its thing.
First, here is the file upload form by itself. The script inside the upload.html page:
document.getElementById("submit").onclick = handleButtonPress;
var httpRequest;
function handleResponse() {
if (httpRequest.readyState == 4 && httpRequest.status == 200) {
document.getElementById("results").innerHTML = httpRequest.responseText;
}
}
function handleButtonPress(e) {
e.preventDefault();
var form = document.getElementById("myform");
var formData = new FormData(form);
httpRequest = new XMLHttpRequest();
httpRequest.onreadystatechange = handleResponse;
httpRequest.open("POST", form.action);
httpRequest.send(formData);
}
And here's the corresponding node script (the important part being form.on('progress')
var http = require('http'),
util = require('util'),
formidable = require('formidable');
http.createServer(function(req, res) {
if (req.url == '/upload' && req.method.toLowerCase() == 'post') {
var form = new formidable.IncomingForm(),
files = [],
fields = [];
form.uploadDir = './files/';
form.keepExtensions = true;
form
.on('progress', function(bytesReceived, bytesExpected) {
console.log('Progress so far: '+(bytesReceived / bytesExpected * 100).toFixed(0)+"%");
})
.on('file', function(name, file) {
files.push([name, file]);
})
.on('error', function(err) {
console.log('ERROR!');
res.end();
})
.on('end', function() {
console.log('-> upload done');
res.writeHead(200, "OK", {
"Content-Type": "text/html", "Access-Control-Allow-Origin": "http://test"
});
res.end('received files: '+util.inspect(files));
});
form.parse(req);
} else {
res.writeHead(404, {'content-type': 'text/plain'});
res.end('404');
}
return;
}).listen(8080);
console.log('listening');
Ok, so that all works as expected. Now here's the simplest socket.io script which I'm hoping to infuse into the previous two to emit the progress info back to my page. Here's the client-side code:
var socket = io.connect('http://test:8080');
socket.on('news', function(data){
console.log('server sent news:', data);
});
And here's the server-side node script:
var http = require('http'),
fs = require('fs');
var server = http.createServer(function(req, res) {
fs.createReadStream('./socket.html').pipe(res);
});
var io = require('socket.io').listen(server);
io.sockets.on('connection', function(socket) {
socket.emit('news', {hello: "world"});
});
server.listen(8080);
So this works fine by itself, but my problem comes when I try to place the socket.io code inside my form.... I've tried placing it anywhere it might remotely make sense, i've tried the asynchronous mode of fs.readFile too, but it just wont send anything back to the client - meanwhile the file upload portion still works fine. Do I need to establish some sort of handshake between the two packages? Help me out here. I'm a front-end guy so I'm not too familiar with this back-end stuff. I'll put this aside for now and move onto other lessons.
Maybe you can create a room for one single client and then broadcast the percentage to this room.
I explained it here: How to connect formidable file upload to socket.io in Node.js