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using stream.pipe make express middleware skipped

im using express and nodejs for my api server,
and now im implementing pdf download (im using pdf-creator-node) for converting html to pdf.
the pdf-creator-node will create a stream when converting a html, and when i pipe it, all my middleware (notFoundHandler, errorHandler,responseLogger) got skipped
router.get(
'/generatePDF', authenticate, schemaValidation({ params: generatePDFschema }),
(req, res, next) => {
generatePDF(details) {
const template = readFile('./src/templates/da-template.html');
const receipt = {
html: template,
data: payload,
type: 'stream'
};
const generatedPdf = pdf.create(receipt, advisOptions);
return generatedPdf;
}
const pdfStream = generatePDF(details);
res.setHeader('Content-type', 'application/pdf');
pdfStream.pipe(res);
},
notFoundHandler,
errorHandler,
responseLogger
);
is there any express api can i use to pipe a stream?

The middleware you show is passed to router.get() AFTER your request handler so it will not get a chance to run unless you call next() in your request handler. When you pass multiple request handlers to a router.get(), they will run sequentially in order and the 2nd one will only get a chance to run if the first one calls next(). Same for the 3rd one, and so on.
Furthermore, pdfStream.pipe(res); does not call next().
I don't know exactly what those middleware functions are supposed to do, but making a guess based on their names, perhaps they are supposed to run BEFORE your request handler, not after so they can put things in place for various error conditions.
If you want further help, then please show the code for those three middleware functions so we can see more specifically what they are trying to do.

How to create an express update route with multiple parameters

I want to update an attribute within a JSON object using fetch PUT. I've created a put function taking in 2 URL parameters
app.put('/trustRoutes/:id/:item', (req, res){
I am able to update the data with a single parameter but since I only want to change one value inside that object, calling put will replace the whole object with my new body.
below is what I've tried.
app.put('/trustRoutes/:id/:item', (req, res) => {
readFile(data => {
const userId = req.params['id/item'];
// have also tried const userId = req.params.id.item
data[userId] = req.body;
//write data back to file
I looked around at other examples but couldn't find any that were updating data instead of GET. If there is one I missed please let me know.

PUT requests are great for completely overwriting a resource, and is idempotent. This answer does a good job explaining idempotency. For updating a resource partially, a PATCH request is a better choice.
app.patch('/trustRoutes/:id/:item', (req, res) => {
readFile(data => {
data[userId] = req.params[id];
data[item] = req.params[item];
// A get request for this resource would now show both of the updated values
// Write file

Getting error 404 for put request (using express and node js) [duplicate]

I am trying to create two routes in my express app. One route, without a parameter will give me a list of choices, the other one with a parameter will give me the choice related to the id.
router.get('/api/choice', choice_controller.get_choices);
router.get('/api/choice/:id', choice_controller.get_choice);
When I go to .../api/choice/?id=1 the api returns the list of choices, and therefore follows the route without the param (/api/choice). How do I make sure that the router does not omit the parameter?
Thanks in advance.
UPDATE
It seems that it does not fire the /api/choice/:id route. If I remove the one without the param, it gives a 404 so. Could someone explain to me why /api/choice/?id=1 is not getting picked up by /api/choice/:id?

Basically, your declared routes are documented in the Express documentation.
The second route is resolved by a URL like /api/choice/hello where 'hello' is mapped into the req object object as:
router.get('/api/choice/:id', function (req, res) {
console.log("choice id is " + req.params.id);
});
What you are actually trying is mapping query parameters.
A URL like /api/choice/?id=1 is resolved by the first router you provided.
Query parameters are easy to get mapped against the request as:
router.get('/api/choice', function (req, res) {
console.log('id: ' + req.query.id);
//get the whole query as!
const queryStuff = JSON.stringify(req.query);
console.log(queryStuff)
});

Neither Node.js PUT or POST routes are presenting the data that is being received

I tried this with a number of different modules and methods.
Even by proving the other modules do work as expected in Node by building a separate test project and testing each module individually.
Posting FROM Node's hosted router to a remote API (not TO Node's hosted API)
This problem is not one of SENDING data to an API. It must IMO a problem in the receiving API's not giving up the data it IS receiving for some reason.
I've proven the PUT or POST calls are sending the data by sending the call to http://httpbin/org. That site shows me I'm sending what I expect to be sending.
Here is how I'm sending. I can even see in the receiving API that that API is certainly getting called successfully.
-- sending -- ((Again. This shows my node.http attempt. But I get the same problem using requestjs, requestifyjs, needlejs))
router.get('/', function (req, res, next) {
var hst = req.headers.host.split(':');
var lookbackURL = 'https://' + req.headers.host + req.baseUrl;
lookbackURL = 'http"httpbin.org/put';
var dat = {
what: 'ever'
, try: 'again'
};
var bdy = JSON.stringify(dat);
var options = {
host: hst[0], port: hst[1], path: req.baseUrl, method: 'PUT'
, headers: { 'Content-Type': 'application/json' }
};
var r = nodeHttp.request(options); r.write(bdy); r.end();
res.sendStatus(200);
});
-- receiving --
router.put('/', function (req, res, next) {
console.log('r', req);
});
No matter what module or method I use, in all cases, the receiving req object doesn't contain the what or try data.
BUT in my test project the data is there as I expect it to be, in all cases.
Doing the same console.log(req); in the test project, reqestjs, requestjs, needlejs, node.http all show a proper body object.
But in this problem there isn't a body object in req.
And sending this put/post to http://httpbin.org I can see the body object is being sent.
Any ideas?

Issue found. And it was something no one on here could have gotten for the code I posted.
For reasons I will not go into I have to take body-parser out this application. This also means app.use() won't have a parser given to it.
And that means I have to deal with getting the data on my own. So I've added a req.on('data') listener to read the chunk from the call to the API.
router.put('/', function (req, res, next) {
var data = '';
req.on('data', function (chunk) {
data += chunk;
.....
});
.....
I also decided to do this as a PUT using Requestify.
This just goes to show how easy it is to become complacent and forget how things really work; the assumption of body-parser (or other things) always being there for instance. Or what it is really doing for you.
NEXT I have to figure out how to get a value out of the `req.on('data) back to the method PUTting to the API. Any tips? Appreciated.

Using the PUT method with Express.js

I'm trying to implement update functionality to an Express.js app, and I'd like to use a PUT request to send the new data, but I keep getting errors using PUT. From everything I've read, it's just a matter of using app.put, but that isn't working. I've got the following in my routes file:
send = function(req, res) {
req.send(res.locals.content);
};
app.put('/api/:company', function(res,req) {
res.send('this is an update');
}, send);
When I use postman to make a PUT request, I get a "cannot PUT /api/petshop" as an error. I don't understand why I can't PUT, or what's going wrong.

You may be lacking the actual update function. You have the put path returning the result back to the client but missing the part when you tell the database to update the data.
If you're using MongoDB and ExpressJS, you could write something like this :
app.put('/api/:company', function (req, res) {
var company = req.company;
company = _.extend(company, req.body);
company.save(function(err) {
if (err) {
return res.send('/company', {
errors: err.errors,
company: company
});
} else {
res.jsonp(company);
}
})
});
This mean stack project may help you as it covers this CRUD functionality which I just used here swapping their articles for your companies. same same.

Your callback function has the arguments in the wrong order.
Change the order of callback to function(req, res).
Don't use function(res, req).

Also if you want to redirect in put or delete (to get adress), you can't use normal res.redirect('/path'), you should use res.redirect(303, '/path') instead. (source)
If not, you'll get Cannot PUT error.

Have you been checking out your headers information?
Because header should be header['content-type'] = 'application/json'; then only you will get the update object in server side (node-express), otherwise if you have content type plain 'text/htm' like that you will get empty req.body in your node app.