Directly returning an object in a promise

Question

Why would this piece of code

app.post('/api/v1/subscribe', (req, res) => {
  lsq.services.get('subscribe')
    .then(service => {
      method: 'POST',
      uri: `http://${service}/api/v1/demo/subscribe`,
      json: req.body,
    })
    .then(rp)
});

throw error

 uri: `http://${service}/api/v1/demo/subscribe`,
    ^
SyntaxError: Unexpected token :

My guess is that JS considers { as function opening braces, not object opening braces. So, are we not allowed to directly return an object in a promise?

score 2 · Accepted Answer · answered Feb 22 '18 at 09:27

2

This isn't related to promises at all, only to the ambiguity of the fat arrow function syntax. The problem is the literal object you return is confused with a function body. Just put it between parenthesis:

app.post('/api/v1/subscribe', (req, res) => {
  lsq.services.get('subscribe')
    .then(service => ({
      method: 'POST',
      uri: `http://${service}/api/v1/demo/subscribe`,
      json: req.body,
    }))
    .then(rp)
});

answered Feb 22 '18 at 09:27

Denys Séguret

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Please just close as a dupe instead of answering – Bergi Feb 22 '18 at 09:38
@Bergi I close many questions as dupe but I'm sorry, I can't be aware of **all** previous questions asked on SO – Denys Séguret Feb 22 '18 at 13:01
Not all of them of course, but this one is rather popular :-) – Bergi Feb 22 '18 at 13:07
I guess I wasn't active enough recently, I hadn't seen it... – Denys Séguret Feb 22 '18 at 13:11
You also don't have any ES6 badge, so I guess I'm just a bit biased… – Bergi Feb 22 '18 at 13:15

Directly returning an object in a promise

1 Answers1