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Next.js E-commerce Example Issue - UnhandledPromiseRejectionWarning: Error: Option requires argument: --port

32 replies
Last updated: Jan 25, 2021
Hi, I’m trying to set up the Next.js E-commerece example but I’ve ran into an issue. I get this error in console 
(node:33819) UnhandledPromiseRejectionWarning: Error: Option requires argument: --port
. In the package.json-file I see that the script 
"dev": "concurrently \"next --port $PORT\" \"cd studio && sanity start\"",
is trying to use a variable called $PORT (I’m assuming), but this variable isn’t defined anywhere in the example.
Jan 25, 2021, 10:33 AM
The studio runs on port 
3333
, but the guide says it will run on 
localhost:3000/studio
Jan 25, 2021, 10:38 AM
I used the “Create project” thing
Jan 25, 2021, 10:38 AM
Maybe I’m not suppose to run 
npm run dev
. But I also have some issues with Vercel when using 
npm start
Jan 25, 2021, 10:41 AM
I think you can pass in a port like so:
$PORT=3000 npm run dev
…but you might as well remove the --port argument together with $PORT in your package.json script!
Jan 25, 2021, 10:42 AM
the template rewrites 
/studio
to localhost:3333 for you, I think that’s why in the guide it saids localhost:3000/studio
Jan 25, 2021, 10:43 AM
I’m not sure where to go from here
Jan 25, 2021, 10:48 AM
Seems like the login helped a bit. Next runs, but the studio (localhost:3000/studio) loads until I get a 5xx error
Jan 25, 2021, 11:05 AM
I also noticed 
sanity.json
has this in it:
  "api": {
    "projectId": "placeholder",
    "dataset": "placeholder"
  },
I tried with placeholder and with my projectId and dataset
Jan 25, 2021, 11:07 AM
Error occurred proxying <http://localhost:3333/studio> Error: connect ECONNREFUSED 127.0.0.1:3333
    at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1146:16) {
  errno: -61,
  code: 'ECONNREFUSED',
  syscall: 'connect',
  address: '127.0.0.1',
  port: 3333
}
Jan 25, 2021, 11:20 AM
looks like the studio is not running on port 3333
Jan 25, 2021, 11:21 AM
could you cd into /studio &amp; run 
sanity start
?
Jan 25, 2021, 11:21 AM
Yeah, the studio runs fine that way
Jan 25, 2021, 11:24 AM
cool, you should be able to go to localhost:3000/studio now I think
Jan 25, 2021, 11:24 AM
(http://localhost:3333 probably when using the standard port with 
sanity start
)
Jan 25, 2021, 11:25 AM
Is there anyway to make it work without having two terminal windows?
Jan 25, 2021, 11:26 AM
It works if I run 
sanity start
in one window and 
npm start
in another
Jan 25, 2021, 11:27 AM
the 
npm run dev
is supposedly the one that’ll run both in one window
Jan 25, 2021, 11:27 AM
npm run dev
in the root should start both your Next and Sanity development servers on localhost:3000 and localhost:3333, respectively
Jan 25, 2021, 11:27 AM
Then I get the port problem again
Jan 25, 2021, 11:28 AM
you could try 
PORT=3000 npm run dev
, or just remove the whole ‘--port $PORT’ part
Jan 25, 2021, 11:29 AM
Ah, I see. I tried that earlier with the $ sign first.
Jan 25, 2021, 11:30 AM
my bad, I think I might have mistakenly left that in 😛
Jan 25, 2021, 11:31 AM
Ok, now it runs fine.
Jan 25, 2021, 11:31 AM
Thanks 🙂
Jan 25, 2021, 11:31 AM
Looks like it's missing an environment variable there. You could do as Derek suggested or create a 
.env
file in your project root folder with this content:
PORT="3000"
Jan 25, 2021, 11:31 AM
The example .env didn’t contain that variable. I also tried adding that, but it doesn’t seem to do anything
Jan 25, 2021, 11:32 AM
(Or rename 
.env.test
to 
.env
and add that variable there)
Jan 25, 2021, 11:32 AM
Sorry about the confusion, Ole, we'll update the starter to include that information 🙂
Jan 25, 2021, 11:32 AM
NODE_ENV=PORT
works
Jan 25, 2021, 11:37 AM
I don’t know what the 
$
sign means, but on macOS it doesn’t seem to read it from .env with it
Jan 25, 2021, 11:37 AM
For simplicity, we should probably just adapt it to run 
next
in dev instead, without the 
--port
flag:
    "dev": "concurrently \"next\" \"cd studio && sanity start\"",
Jan 25, 2021, 11:49 AM
Updated the starter itself as well now. Thanks for the feedback, Ole - and thanks for helping out, Derek 🙌
Jan 25, 2021, 11:54 AM

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