web/pages/_document.tsx (21 lines of code) (raw):
/**
* Copyright 2021 Google LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import { ServerStyleSheets } from "@material-ui/core";
import Document, {
DocumentContext,
DocumentInitialProps,
Head,
Html,
Main,
NextScript,
} from "next/document";
import { Children } from "react";
import { enabledGa, GA_MEASUREMENT_ID } from "../src/gtag";
export default class MyDocument extends Document {
render(): JSX.Element {
return (
<Html lang={this.props.locale}>
<Head>
<link
rel="stylesheet"
href="https://fonts.googleapis.com/css?family=Roboto:300,400,500,700&display=swap"
/>
<link rel="icon" href="/favicon.ico" />
{enabledGa ? (
<>
<script
async
src={`https://www.googletagmanager.com/gtag/js?id=${GA_MEASUREMENT_ID}`}
/>
<script
dangerouslySetInnerHTML={{
__html: `
window.dataLayer = window.dataLayer || [];
function gtag(){dataLayer.push(arguments);}
gtag('js', new Date());
gtag('config', '${GA_MEASUREMENT_ID}', {
page_path: window.location.pathname,
});
`,
}}
/>
</>
) : null}
</Head>
<body>
<Main />
<NextScript />
</body>
</Html>
);
}
}
MyDocument.getInitialProps = async (
ctx: DocumentContext
): Promise<DocumentInitialProps> => {
const sheets = new ServerStyleSheets();
const originalRenderPage = ctx.renderPage;
ctx.renderPage = () =>
originalRenderPage({
enhanceApp: (App) => (props) => sheets.collect(<App {...props} />),
});
const initialProps = await Document.getInitialProps(ctx);
return {
...initialProps,
styles: [
...Children.toArray(initialProps.styles),
sheets.getStyleElement(),
],
};
};