Build Fails With Error for Unhandled 'error' event

[ajaytech]

Bug report

After Adding Custom Server.js the Build Fails With Error:
DeprecationWarning: Unhandled promise rejections are deprecated.

Describe the bug

In the Console After Trying Multiple Times Clearing the node_modules and .next files for Multiple Versions of NodeJS(v10.13.0, v10.16.3 and v13.8.0). Repeted Error is shown.

DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
    at emitDeprecationWarning (internal/process/promises.js:95:13)
    at emitWarning (internal/process/promises.js:88:3)
    at emitPromiseRejectionWarnings (internal/process/promises.js:120:9)
    at process._tickCallback (internal/process/next_tick.js:69:34)

To Reproduce:

Not Using next.config.js
in Pages: NextJS: _app.js is present with server.js

###_app.js With Context API and GraphQL

import App, { Container } from "next/app";
import React from "react";
import "semantic-ui-css/semantic.min.css";
import "video.js/dist/video-js.css";
import "@videojs/themes/dist/fantasy/index.css";


import "react-markdown-editor-lite/lib/index.css";
import "react-quill/dist/quill.snow.css";
// import "draft-js/dist/Draft.css";
import "react-draft-wysiwyg/dist/react-draft-wysiwyg.css";
import "react-toastify/dist/ReactToastify.css";
import "./app.css";


//Adding Apollo
import { ApolloClient } from "apollo-client";
import { InMemoryCache } from "apollo-cache-inmemory";
import { ApolloProvider, Mutation } from "react-apollo";
import { createUploadLink } from "apollo-upload-client";

//Adding Global Context

import { BuilderProvider } from "../components/context/BuilderState";
import { withRouter } from "next/router";
import { parseCookies } from "../lib/parseCookies";

const apolloCache = new InMemoryCache();

const uploadLink = createUploadLink({
  uri: "http://localhost:3000/api/graphql",
  headers: {
    "keep-alive": "true"
  }
});

// Temporary wrapper to use React Context
const InjectRouterContext = props => {
  const { cookies, router } = props;
  const someInject = withRouter(({ children }) => {

    return (
      <BuilderProvider cookiesSSRPass={cookies} value={router}>
        {children}
      </BuilderProvider>
    );
  });
  return someInject;
};
const client = new ApolloClient({
  cache: apolloCache,
  link: uploadLink
});

class MyApp extends App {
  static async getInitialProps(appArgument) {
 
    const { ctx } = appArgument;
    const { query, req } = ctx;
  
    const cookies = parseCookies(req);
    return {
      query,
      cookies,
      renderFrom: "demo.demo.com"
    };
  }
  render() {
    const { Component, pageProps } = this.props;

    const InjectRouterContxCookie = InjectRouterContext(this.props);
    
    return (
      <InjectRouterContxCookie>
        <ApolloProvider client={client}>
          <Component {...pageProps} />
        </ApolloProvider>
      </InjectRouterContxCookie>
    );
  }
}

export default MyApp;

Content of server.js:

const { createServer } = require("http");
const { parse } = require("url");
const next = require("next");
const dev = process.env.NODE_ENV !== "production";
const app = next({ dev });
const handle = app.getRequestHandler();

app.prepare().then(() => {
  createServer((req, res) => {
    // Be sure to pass `true` as the second argument to `url.parse`.
    // This tells it to parse the query portion of the URL.
    const parsedUrl = parse(req.url, true);
    const { pathname, query } = parsedUrl;

    if (pathname === "/demo.demo.com") {
      app.render(req, res, "/demo.demo.com", query);
    } else if (pathname === "/demo1.demo1.com") {
      app.render(req, res, "/demo1.demo.com1", query);
    } else {
      handle(req, res, parsedUrl);
    }
  }).listen(3000, err => {
    if (err) throw err;
    console.log("> Ready on http://demo.demo.com:3000");
  });
});

The Build is Failing Recently After Adding the Server.js File.

Screenshots

System information

• OS: [macOS]
• Version of Next.js: [9.3.2]
• Version of Node.js: [e.g. 10.13.0, 10.16.3 and 13.8.0]

Additional context

Recently Added Carousel With react-items-carousel and Dynamic Sub-routing Before that Build was successful with NextJS

[jamesmosier]

Hi @ajaytech.

1. Have you tried removing each piece of newly added code/functionality until the build works? Working backwards is a good start to finding the issue!
2. Do you have a more complete reproduction of this issue?

[ajaytech]

@jamesmosier
Thanks for Reply!

I am looking for way to reproduce the error and working backwards to check what is breaking.

But is there some way to debug and find Call Stack After Build.

I have tested the same scenario in a GCP Machine and it gives the error on Validation Fail of Build with Node 10.13 and Next 9.3.2 and 9.4.4

dev@up-dev:~/Ajay/code$ yarn run build
yarn run v1.22.4
$ next build 
(node:29998) ExperimentalWarning: The fs.promises API is experimental
Creating an optimized production build  
Compiled successfully.
Warning: You have opted-out of Automatic Static Optimization due to `getInitialProps` in `pages/_app`. This does not opt-out pages with `getStaticProps`
Read more: https://err.sh/next.js/opt-out-auto-static-optimization
> Build error occurred
{ Error: Could not find a valid build in the '/home/dev/Ajay/code/.next' directory! Try building your app with 'next build' before starting the server.
    at Server.readBuildId (/home/dev/Ajay/code/node_modules/next/dist/next-server/server/next-server.js:105:355)
    at new Server (/home/dev/Ajay/code/node_modules/next/dist/next-server/server/next-server.js:3:120)
    at createServer (/home/dev/Ajay/code/node_modules/next/dist/server/next.js:2:328)
    at Object.BS8E (/home/dev/Ajay/code/.next/server/static/okr7NtbxtKr2qCXHWYL3F/pages/server.js:118:13)
    at __webpack_require__ (/home/dev/Ajay/code/.next/server/static/okr7NtbxtKr2qCXHWYL3F/pages/server.js:23:31)
    at Object.19 (/home/dev/Ajay/code/.next/server/static/okr7NtbxtKr2qCXHWYL3F/pages/server.js:99:18)
    at __webpack_require__ (/home/dev/Ajay/code/.next/server/static/okr7NtbxtKr2qCXHWYL3F/pages/server.js:23:31)
    at /home/dev/Ajay/code/.next/server/static/okr7NtbxtKr2qCXHWYL3F/pages/server.js:91:18
    at Object.<anonymous> (/home/dev/Ajay/code/.next/server/static/okr7NtbxtKr2qCXHWYL3F/pages/server.js:94:10)
    at Module._compile (internal/modules/cjs/loader.js:688:30) type: 'Error' }
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

-Regards
Ajay

[jamesmosier]

There is no way to find the call stack after the build to my knowledge. As far as your issues, I am not sure. It is hard to tell from just seeing the _app and server file unfortunately.

[ajaytech]

@jamesmosier : It got solved in the dev mode i was getting a warning linked to issue with semantic-ui (Development issue not library issue) which was not breaking anything but in build phase it was failing.