I want to download a pdf file when clicking a button on a html page.The html page is deployed on nodejs.And the pdf file is on apache http server.So the html page and nodejs server are on the same domain, but the html page and apache http server are cross domain.
Can I do like this?
when I click the button, I send a request to nodejs, and nodejs get file from apache http server, and then send response to client(browser).Can this case work?
And if the pdf file is very large, I can wait until nodejs get it over and then send response to client.I just want to achieve this goal, download this file like <a href="xxx" download="yyy">Download<a>
Can I achieve this goal?
Yes, you can do that. Browser -> Node.JS Server -> Http Server -> Node.JS Server -> Browser Using Request module you can stream files between req and res. https://www.npmjs.com/package/request#streaming
Example:
http.createServer(function (req, resp) {
if (req.url === '/doodle.png') {
r.get('http://google.com/doodle.png').pipe(resp)
}
}).listen(port);
Related
I have an Express/Node server with an endpoint to provide the PDF, and a React client that is making a get request to that endpoint.
Currently the PDF is in what I believe is raw pdf binary data string form (obtained from the response of a separate api request), and on the client side I want to click a button in the browser and have the PDF download.
I'm not sure what is needed on the server side and on the client side to successfully trigger
the download on request.
Do I need to convert the binary PDF data to something on the server side first? Or does this get handled on the client side?
And what would be the code to do this?
Server:
const servePDF = async (req, res) => {
const pdfBinary = '%PDF-1.4 %âãÏÓ 2 0 obj <</ColorSpa ......'
~code here to send pdf as response~
}
Client:
const downloadPDF = async () => {
~get request code here, to run onClick of a button, to download file~
}
I have videos stored on a server (server1) that some clients have no access to, and I have another server (server2) that has access to server1 and the clients have access to.
I want those clients to be able to watch those videos through server2 on their browsers.
I can't just redirect them to server1 cuz they can't access it.
I can't download and save the videos on server2 cuz I don't have that much of space on it.
I know how to stream a local video to a client using chunks.
I know how to download and save a video using http.
Is there any way I can stream those videos from server1 to the clients using nodejs on server2?
The request module is deprecated but they have a nice streaming example
const request = require('request');
http.createServer(function (req, resp) {
if (req.url === '/doodle.png') {
if (req.method === 'GET') {
request.get('http://example.com/doodle.png').pipe(resp)
}
}
})
You can use the request module, it's still rock, or to adapt to any other request alternative or the built in http module.
I am trying to setup a login system on a website.
In order to do that, I have to load http only cookies.
In order to load them, I have to send them back to the client via the response object in the createServer function when https starts up.
I have successfully done that via here:
setting up https cookie in nodejs
The problem is twofold.
The https server cookie only loads if I include the port number in the url.
How do I get it to load without including the port number?
When the server kicks in and loads the cookie, the static index.html that was always supposed to load on the client, doesn't load and instead all i get is what was written into the response object on the server. How do I get to load the cookie, and just load that static html file?
I have tried sending in the entire html file as a respnose from the server side. But I'm not sure about that, plus i get MIME type problems in the browser.
I am not sure for the first part but for 2nd one,
you have to properly mention about response data type in response header.
so your should be something like this one:
var app = express(); app.get('/test', function(req, res) { res.sendFile('views/test.html', {root:__dirname}) });
For your first part of the question "How do I get it to load without including the port number?" You can try creating virtual host e.g for localhost:3000 will be something.xyz.
And for your second part you need to serve index.html with render method as follow
server.get('/', function (req, res) {
res.render('index', { greeting: 'Welcome' });
});
Where index is you static file inside view directory.
I've created a small demo, that might get you on the right track:
https://github.com/bergur/simple-server-with-websocket
This example includes:
https web server
websocket server
logic to get the cookies
serving a temp.html file without express
example of javascript class
example of dependency injection in nodejs
I'm trying to run this code
module.exports = async (req, res, next) => {
res.set('Content-Type', 'text/javascript');
const response = {};
res.status(200).render('/default.js', { response });
await fn(response);
};
fn is a function that calls an api to a service that will output to the client something. but its dependent on the default.js file to be loaded first. How can do something like
res.render('/default.js', { response }).then(async() => {
await fn(response);
};
tried it, but doesn't seem to like the then()
also, fn doesn't return data to the client, it calls an api service that is connected with the web sockets opened by the code from default.js that is rendered.
do i have to make an ajax request for the fn call and not call it internally?
any ideas?
Once you call res.render(), you can send no more data to the client, the http response has been sent and the http connection is done - you can't send any more to it. So, it does you no good to try to add something more to the response after you call res.render().
It sounds like you're trying to put some data INTO the script that you send to the browser. Your choices for that are to either:
Get the data you need to with let data = await fn() before you call res.render() and then pass that to res.render() so your template engine can put that data into the script file that you send the server (before you send it).
You will need to change the script file template to be able to do this so it has appropriate directives to insert data into the script file and you will have to be very careful to format the data as Javascript data structures.
Have a script in the page make an ajax call to get the desired data and then do your task in client-side Javascript after the page is already up and running.
It looks like it might be helpful for you to understand the exact sequence of things between browser and server.
Browser is displaying some web page.
User clicks on a link to a new web page.
Browser requests new web page from the server for a particular URL.
Server delivers HTML page for that URL.
Browser parses that HTML page and discovers some other resources required to render the page (script files, CSS files, images, fonts, etc...)
Browser requests each of those other resources from the server
Server gets a request for each separate resource and returns each one of them to the browser.
Browser incorporates those resources into the HTML page it previously downloaded and parsed.
Any client side scripts it retrieved for that page are then run.
So, the code you show appears to be a route for one of script files (in step 5 above). This is where it fits into the overall scheme of loading a page. Once you've returned the script file to the client with res.render(), it has been sent and that request is done. The browser isn't connected to your server anymore for that resource so you can't send anything else on that same request.
I want to open a browser popup for client site on rest api request to nodejs backend.
I had tried
res.setHeader('Content-Type', 'text/html');
res.render('index', { title: 'Hey', message: 'Hello' });
But it still returning html codes as data to the client.
I also used window.open but window is not defined in server side
Is there anyway to make my backend redirect or render html form on api request!
the following image is how the client get response
If you want the browser change page/view, you need something like location.href = /yourview.html
If you want fill your popup with html built on the server, you need to get it using fetch or XMLHttpRequest or something built on top of them (for example axios, like you did) and then attach to the dom.
Once you got it, you can show the popup. But you are on the client side.
res.render return rendered html. http://expressjs.com/en/api.html#app.render