import * as React from "react";
import Document, { Html, Head, Main, NextScript } from "next/document";
import createEmotionServer from "@emotion/server/create-instance";
import { theme } from "../theme";
import createEmotionCache from "../createEmotionCache";
export default class MyDocument extends Document {
render() {
return (
{/* PWA primary color */}
);
}
}
// `getInitialProps` belongs to `_document` (instead of `_app`),
// it's compatible with static-site generation (SSG).
MyDocument.getInitialProps = async (ctx) => {
// Resolution order
//
// On the server:
// 1. app.getInitialProps
// 2. page.getInitialProps
// 3. document.getInitialProps
// 4. app.render
// 5. page.render
// 6. document.render
//
// On the server with error:
// 1. document.getInitialProps
// 2. app.render
// 3. page.render
// 4. document.render
//
// On the client
// 1. app.getInitialProps
// 2. page.getInitialProps
// 3. app.render
// 4. page.render
const originalRenderPage = ctx.renderPage;
// You can consider sharing the same emotion cache between all the SSR requests to speed up performance.
// However, be aware that it can have global side effects.
const cache = createEmotionCache();
const { extractCriticalToChunks } = createEmotionServer(cache);
ctx.renderPage = () =>
originalRenderPage({
// eslint-disable-next-line react/display-name
enhanceApp: (App) => (props) => ,
});
const initialProps = await Document.getInitialProps(ctx);
// This is important. It prevents emotion to render invalid HTML.
// See https://github.com/mui-org/material-ui/issues/26561#issuecomment-855286153
const emotionStyles = extractCriticalToChunks(initialProps.html);
const emotionStyleTags = emotionStyles.styles.map((style) => (
));
return {
...initialProps,
// Styles fragment is rendered after the app and page rendering finish.
styles: [
...React.Children.toArray(initialProps.styles),
...emotionStyleTags,
],
};
};