@netlify/next-runtime/dist/run/handlers/server.js

Run Next.js seamlessly on Netlify

import { toComputeResponse, toReqRes } from '@fastly/http-compute-js';
import { readFileSync } from 'node:fs';
import { join } from 'node:path/posix';
import { RUN_DIR } from '../constants.js';
import { setCacheControlHeaders, setCacheTagsHeaders, setVaryHeaders } from '../headers.js';
import { nextResponseProxy } from '../revalidate.js';
let nextHandler, nextConfig, cacheEntry;
export default async (request) => {
    if (!nextHandler) {
        // set the server config
        const { getRunConfig, setRunConfig } = await import('../config.js');
        nextConfig = await getRunConfig();
        setRunConfig(nextConfig);
        cacheEntry = await getCacheEntry(request);
        const { getMockedRequestHandlers } = await import('./next.cjs');
        [nextHandler] = await getMockedRequestHandlers({
            port: 3000,
            hostname: 'localhost',
            dir: RUN_DIR,
            isDev: false,
        });
    }
    const { req, res } = toReqRes(request);
    const resProxy = nextResponseProxy(res);
    resProxy.prependListener('_headersSent', (event) => {
        const headers = new Headers(event.headers);
        setCacheControlHeaders(headers);
        setCacheTagsHeaders(request, headers, cacheEntry);
        setVaryHeaders(headers, request, nextConfig);
        event.headers = Object.fromEntries(headers.entries());
        // console.log('Modified response headers:', JSON.stringify(event.headers, null, 2))
    });
    // temporary workaround for https://linear.app/netlify/issue/ADN-111/
    delete req.headers['accept-encoding'];
    try {
        // console.log('Next server request:', req.url)
        await nextHandler(req, resProxy);
    }
    catch (error) {
        console.error(error);
        resProxy.statusCode = 500;
        resProxy.end('Internal Server Error');
    }
    // log the response from Next.js
    const response = {
        headers: resProxy.getHeaders(),
        statusCode: resProxy.statusCode,
    };
    // console.log('Next server response:', JSON.stringify(response, null, 2))
    return toComputeResponse(resProxy);
};
const prerenderManifest = JSON.parse(readFileSync(join(process.cwd(), '.next/prerender-manifest.json'), 'utf-8'));
const getCacheEntry = async (request) => {
    // dynamically importing to avoid calling NetlifyCacheHandler beforhand
    // @ts-expect-error
    const NetlifyCacheHandler = await import('../../../dist/run/handlers/cache.cjs');
    // Have to assign NetlifyCacheHandler.default to new variable to prevent error: `X is not a constructor`
    const CacheHandler = NetlifyCacheHandler.default;
    const cache = new CacheHandler({
        _appDir: true,
        revalidateTags: [],
        _requestHandler: {},
    });
    const path = new URL(request.url).pathname;
    // Checking if route is in prerender manifest before retrieving pageData from Blob
    if (prerenderManifest.routes[path]) {
        return await cache.get(path, { type: 'json' });
    }
};