{statusCode ? `${statusCode}: ${title}` : 'Application error: a client-side exception has occurred'}

import React from 'react' import Head from '../shared/lib/head' import type { NextPageContext } from '../shared/lib/utils' const statusCodes: { [code: number]: string } = { 400: 'Bad Request', 404: 'This page could not be found', 405: 'Method Not Allowed', 500: 'Internal Server Error', } export type ErrorProps = { statusCode: number hostname?: string title?: string withDarkMode?: boolean } function _getInitialProps({ req, res, err, }: NextPageContext): Promise | ErrorProps { const statusCode = res && res.statusCode ? res.statusCode : err ? err.statusCode! : 404 let hostname if (typeof window !== 'undefined') { hostname = window.location.hostname } else if (req) { const { getRequestMeta } = require('../server/request-meta') as typeof import('../server/request-meta') const initUrl = getRequestMeta(req, 'initURL') if (initUrl) { const url = new URL(initUrl) hostname = url.hostname } } return { statusCode, hostname } } const styles: Record = { error: { // https://github.com/sindresorhus/modern-normalize/blob/main/modern-normalize.css#L38-L52 fontFamily: 'system-ui,"Segoe UI",Roboto,Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji"', height: '100vh', textAlign: 'center', display: 'flex', flexDirection: 'column', alignItems: 'center', justifyContent: 'center', }, desc: { lineHeight: '48px', }, h1: { display: 'inline-block', margin: '0 20px 0 0', paddingRight: 23, fontSize: 24, fontWeight: 500, verticalAlign: 'top', }, h2: { fontSize: 14, fontWeight: 400, lineHeight: '28px', }, wrap: { display: 'inline-block', }, } /** * `Error` component used for handling errors. */ export default class Error

extends React.Component

{ static displayName = 'ErrorPage' static getInitialProps = _getInitialProps static origGetInitialProps = _getInitialProps render() { const { statusCode, withDarkMode = true } = this.props const title = this.props.title || statusCodes[statusCode] || 'An unexpected error has occurred' return (