fetch graphql data from nodejs to nextjs (SSR) - node.js

Question

I have nextjs Project, where I use SSR for fetch data from nodejs(graphql) but it works only localhost(dev/production), When I upload the project on vercel I get "500: Internal Server Error", I will share my code and required details below:
I use "graphql-request" on Nextjs
import { gql, request } from "graphql-request";
export async function getServerSideProps(context) {
const endPoint = "http://localhost:4000/";
const query = gql`
query {
exactlyUser(id: "63c3cf0aea56b467893c92d3") {
username
}
}
`;
const data = await request(endPoint, query);
return {
props: {
data: data,
},
};
}
I also give you vercel Error:
[HEAD] /_next/data/U_aH1k5dl2EQA1IzXATL6/index.json
2023-01-17T16:52:11.277Z ddd8e632-1ffa-4772-94c0-aa01e2348bb7 ERROR FetchError: request to http://localhost:4000/ failed, reason: connect ECONNREFUSED 127.0.0.1:4000
at ClientRequest.<anonymous> (/var/task/node_modules/node-fetch/lib/index.js:1491:11)
at ClientRequest.emit (node:events:513:28)
at Socket.socketErrorListener (node:_http_client:494:9)
at Socket.emit (node:events:513:28)
at emitErrorNT (node:internal/streams/destroy:151:8)
at emitErrorCloseNT (node:internal/streams/destroy:116:3)
at process.processTicksAndRejections (node:internal/process/task_queues:82:21) {
type: 'system',
errno: 'ECONNREFUSED',
code: 'ECONNREFUSED',
page: '/'
}
RequestId: ddd8e632-1ffa-4772-94c0-aa01e2348bb7 Error: Runtime exited with error: exit status 1
Runtime.ExitError

Answer 1

Seems like when you deploy the Next.js app to Vercel, the API is not accessible. This is the cause of the "500: Internal Server Error" you're seeing.
Try to change the API endpoint URL to the publicly accessible URL of your GraphQL API, instead of using "http://localhost:4000/". This should allow the Next.js app to fetch data from the API when it's running on Vercel.
Avoid hardcoding the API endpoint.