express res.send as result of promise
I'm not understanding what's going on...
Using q promises, this works:
const deferred = q.defer();
deferred.resolve('Hellow');
const myPromise = deferred.promise;
router.get('/items', (req, res) => {
myPromise.then((result) => res.send(result));
});
but this doesn't, it keeps the browser like if the request never ends:
router.get('/items', (req, res) => {
myPromise.then(res.send);
});
What's wrong?
node.js express
asked Jul 4 '16 at 14:43
Miquel
4,40143562
add a comment |
I'm not understanding what's going on...
Using q promises, this works:
const deferred = q.defer();
deferred.resolve('Hellow');
const myPromise = deferred.promise;
router.get('/items', (req, res) => {
myPromise.then((result) => res.send(result));
});
but this doesn't, it keeps the browser like if the request never ends:
router.get('/items', (req, res) => {
myPromise.then(res.send);
});
What's wrong?
node.js express
asked Jul 4 '16 at 14:43
Miquel
4,40143562
add a comment |
I'm not understanding what's going on...
Using q promises, this works:
const deferred = q.defer();
deferred.resolve('Hellow');
const myPromise = deferred.promise;
router.get('/items', (req, res) => {
myPromise.then((result) => res.send(result));
});
but this doesn't, it keeps the browser like if the request never ends:
router.get('/items', (req, res) => {
myPromise.then(res.send);
});
What's wrong?
node.js express
asked Jul 4 '16 at 14:43
Miquel
4,40143562
I'm not understanding what's going on...
Using q promises, this works:
const deferred = q.defer();
deferred.resolve('Hellow');
const myPromise = deferred.promise;
router.get('/items', (req, res) => {
myPromise.then((result) => res.send(result));
});
but this doesn't, it keeps the browser like if the request never ends:
router.get('/items', (req, res) => {
myPromise.then(res.send);
});
What's wrong?
node.js express
node.js express
asked Jul 4 '16 at 14:43
Miquel
4,40143562
asked Jul 4 '16 at 14:43
Miquel
4,40143562
asked Jul 4 '16 at 14:43
Miquel
4,40143562
asked Jul 4 '16 at 14:43
Miquel
4,40143562
asked Jul 4 '16 at 14:43
Miquel
4,40143562
4,40143562
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
Below is the fragment of the express library related to res.send:
res.send = function send(body) {
var chunk = body;
var encoding;
var len;
var req = this.req;
var type;
// settings
var app = this.app;
// allow status / body
if (arguments.length === 2) {
// res.send(body, status) backwards compat
if (typeof arguments[0] !== 'number' && typeof arguments[1] === 'number') {
deprecate('res.send(body, status): Use res.status(status).send(body) instead');
this.statusCode = arguments[1];
} else {
deprecate('res.send(status, body): Use res.status(status).send(body) instead');
this.statusCode = arguments[0];
chunk = arguments[1];
}
}
//.....
As you can see, there are lots of this references. In your case myPromise.then(res.send) the this refers to promise object, not to res, that's why your code doesn't work.
You can change the context by using .bind method, so this will refer to res object:
router.get('/items', (req, res) => {
myPromise.then(res.send.bind(res));
});
answered Jul 4 '16 at 14:50
Engineer
36.3k97383
.bind-thisevil, thanks, there should be a tag for this :)
– Miquel
Jul 4 '16 at 17:41
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Below is the fragment of the express library related to res.send:
res.send = function send(body) {
var chunk = body;
var encoding;
var len;
var req = this.req;
var type;
// settings
var app = this.app;
// allow status / body
if (arguments.length === 2) {
// res.send(body, status) backwards compat
if (typeof arguments[0] !== 'number' && typeof arguments[1] === 'number') {
deprecate('res.send(body, status): Use res.status(status).send(body) instead');
this.statusCode = arguments[1];
} else {
deprecate('res.send(status, body): Use res.status(status).send(body) instead');
this.statusCode = arguments[0];
chunk = arguments[1];
}
}
//.....
As you can see, there are lots of this references. In your case myPromise.then(res.send) the this refers to promise object, not to res, that's why your code doesn't work.
You can change the context by using .bind method, so this will refer to res object:
router.get('/items', (req, res) => {
myPromise.then(res.send.bind(res));
});
answered Jul 4 '16 at 14:50
Engineer
36.3k97383
.bind-thisevil, thanks, there should be a tag for this :)
– Miquel
Jul 4 '16 at 17:41
add a comment |
Below is the fragment of the express library related to res.send:
res.send = function send(body) {
var chunk = body;
var encoding;
var len;
var req = this.req;
var type;
// settings
var app = this.app;
// allow status / body
if (arguments.length === 2) {
// res.send(body, status) backwards compat
if (typeof arguments[0] !== 'number' && typeof arguments[1] === 'number') {
deprecate('res.send(body, status): Use res.status(status).send(body) instead');
this.statusCode = arguments[1];
} else {
deprecate('res.send(status, body): Use res.status(status).send(body) instead');
this.statusCode = arguments[0];
chunk = arguments[1];
}
}
//.....
As you can see, there are lots of this references. In your case myPromise.then(res.send) the this refers to promise object, not to res, that's why your code doesn't work.
You can change the context by using .bind method, so this will refer to res object:
router.get('/items', (req, res) => {
myPromise.then(res.send.bind(res));
});
answered Jul 4 '16 at 14:50
Engineer
36.3k97383
.bind-thisevil, thanks, there should be a tag for this :)
– Miquel
Jul 4 '16 at 17:41
add a comment |
Below is the fragment of the express library related to res.send:
res.send = function send(body) {
var chunk = body;
var encoding;
var len;
var req = this.req;
var type;
// settings
var app = this.app;
// allow status / body
if (arguments.length === 2) {
// res.send(body, status) backwards compat
if (typeof arguments[0] !== 'number' && typeof arguments[1] === 'number') {
deprecate('res.send(body, status): Use res.status(status).send(body) instead');
this.statusCode = arguments[1];
} else {
deprecate('res.send(status, body): Use res.status(status).send(body) instead');
this.statusCode = arguments[0];
chunk = arguments[1];
}
}
//.....
As you can see, there are lots of this references. In your case myPromise.then(res.send) the this refers to promise object, not to res, that's why your code doesn't work.
You can change the context by using .bind method, so this will refer to res object:
router.get('/items', (req, res) => {
myPromise.then(res.send.bind(res));
});
answered Jul 4 '16 at 14:50
Engineer
36.3k97383
Below is the fragment of the express library related to res.send:
res.send = function send(body) {
var chunk = body;
var encoding;
var len;
var req = this.req;
var type;
// settings
var app = this.app;
// allow status / body
if (arguments.length === 2) {
// res.send(body, status) backwards compat
if (typeof arguments[0] !== 'number' && typeof arguments[1] === 'number') {
deprecate('res.send(body, status): Use res.status(status).send(body) instead');
this.statusCode = arguments[1];
} else {
deprecate('res.send(status, body): Use res.status(status).send(body) instead');
this.statusCode = arguments[0];
chunk = arguments[1];
}
}
//.....
As you can see, there are lots of this references. In your case myPromise.then(res.send) the this refers to promise object, not to res, that's why your code doesn't work.
You can change the context by using .bind method, so this will refer to res object:
router.get('/items', (req, res) => {
myPromise.then(res.send.bind(res));
});
answered Jul 4 '16 at 14:50
Engineer
36.3k97383
edited Jul 4 '16 at 14:57
answered Jul 4 '16 at 14:50
Engineer
36.3k97383
answered Jul 4 '16 at 14:50
Engineer
36.3k97383
answered Jul 4 '16 at 14:50
Engineer
36.3k97383
36.3k97383
.bind-thisevil, thanks, there should be a tag for this :)
– Miquel
Jul 4 '16 at 17:41
add a comment |
.bind-thisevil, thanks, there should be a tag for this :)
– Miquel
Jul 4 '16 at 17:41
.bind-this evil, thanks, there should be a tag for this :)– Miquel
Jul 4 '16 at 17:41
.bind-this evil, thanks, there should be a tag for this :)– Miquel
Jul 4 '16 at 17:41
add a comment |
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