How to return value inestead promise in this function?

Question

I'm trying to make the connection with MongoDB database but I can't to export database object, inestead export a promise.

What I would be missing?

index.js

export const db = async() => { 
  return await MongoClient.connect(MONGO_URL)
}

I have also tried this way:

export const db = async() => { 
  const result = await MongoClient.connect(MONGO_URL)
  return result
}

resolvers.js

import { db } from '/mongodb'

This function returns Async Function db

I have also tried this way: `export const db = async() => { const result = await MongoClient.connect(MONGO_URL) return result }` — Alejandro Uray, Dec 23 '18 at 13:42
`What I would be missing?` time. you can not return/export a value that does not exist (yet). That's what Promises are/are dealing with; a value that will be available at some point in the future, but not yet. — Thomas, Dec 23 '18 at 13:56

xianshenglu · Accepted Answer · 2018-12-23T13:50:36.047

0

try this:

const db = async() => { 
  return await MongoClient.connect(MONGO_URL)
}

export const dbResult=db()

Then

import { dbResult} from './mongodb'
dbResult.then(res=>{
     //see what they are
     //console.log(dbResult,res)
})

edited Dec 23 '18 at 13:50

answered Dec 23 '18 at 13:43

xianshenglu

`const Posts = dbResult.collection('messages')` Returns `dbResult.collection is not a function` – Alejandro Uray Dec 23 '18 at 13:50
@AlejandroUray ?? – xianshenglu Dec 23 '18 at 13:51
@AlejandroUray,updated, try again, `dbResult` is a `promise`, you can't call it directly, see the console. – xianshenglu Dec 23 '18 at 13:55
you can simplify this to `export const dbResult = MongoClient.connect(MONGO_URL);` – Thomas Dec 23 '18 at 13:59
@Thomas, that's because I don't know `MongoClient`. I just know `promise` and `async`. – xianshenglu Dec 23 '18 at 14:02
Thanks @xianshenglu I solved! – Alejandro Uray Dec 23 '18 at 14:47

score 0 · Answer 2 · answered Dec 23 '18 at 13:52

0

The reason is because you are exporting an async function (promise). What you could do is:

1) Change to require() over import (generally better, ES6 modules is iffy)

2) Do something like const database = await (require('./mongodb').db())

answered Dec 23 '18 at 13:52

sausage

2 Answers2