proxy.js

const fs = require('fs');
const dotenv = require('dotenv');
const express = require('express');
const next = require('next');
const { createProxyMiddleware } = require('http-proxy-middleware');

// .env.localまたは.envファイルを読み込む
const dotenvFiles = ['.env.local', '.env'];
for (const envFile of dotenvFiles) {
  if (fs.existsSync(envFile)) {
    const stats = fs.statSync(envFile);
    if (stats.isFile()) {
      dotenv.config({ path: envFile });
      break;
    }
  }
}

const SITE_URL = process.env.SITE_URL;
const API_URL = process.env.NEXT_PUBLIC_CUCULUS_API_URL;

const siteUrl = new URL(SITE_URL);
const apiUrl = new URL(API_URL);

const dev = process.env.STAGE !== 'production';
const app = next({ dev });
const handle = app.getRequestHandler();

// Next.js を localhost:3000 で起動
app.prepare().then(() => {
  const server = express();

  // .well-known/*へのリクエストをプロキシする
  server.use(
    '/.well-known/*',
    createProxyMiddleware({
      target: API_URL,
      changeOrigin: true,
    }),
  );

  // users/*へのリクエストをプロキシする
  server.use(
    '/users/*',
    createProxyMiddleware({
      target: API_URL,
      changeOrigin: true,
    }),
  );

  // nodeinfo/*へのリクエストをプロキシする
  server.use(
    '/nodeinfo/*',
    createProxyMiddleware({
      target: API_URL,
      changeOrigin: true,
    }),
  );

  // inboxへのリクエストをプロキシする
  server.use(
    '/inbox',
    createProxyMiddleware({
      target: API_URL,
      changeOrigin: true,
    }),
  );

  server.all('*', (req, res) => {
    return handle(req, res);
  });
  server.listen(siteUrl.port, (err) => {
    if (err) throw err;
    console.log(`> Ready on ${SITE_URL}`);
  });
});

// localhost:8080 へのアクセスを 開発環境 にプロキシ
const proxy = express();
proxy.use(
  '/',
  createProxyMiddleware({
    target: 'https://api.develop.cuculus.jp',
    changeOrigin: true,
    secure: false,
    on: {
      proxyReq: (proxyReq) => {
        proxyReq.setHeader('host', siteUrl.hostname);
      },
      proxyRes: (proxyRes) => {
        proxyRes.headers['Access-Control-Allow-Origin'] = SITE_URL;
        proxyRes.headers['Access-Control-Allow-Credentials'] = 'true';
        // Set-Cookieが返却された際、Domain=.localhost;に変更
        const setCookie = proxyRes.headers['set-cookie'] ?? undefined;
        if (setCookie) {
          const pattern = /Domain=\.[a-zA-Z0-9-]*\.cuculus\.jp;/;
          const cookies = [];
          setCookie.forEach((value) => {
            cookies.push(
              value.replace(pattern, `Domain=.${siteUrl.hostname};`),
            );
          });
          proxyRes.headers['set-cookie'] = cookies;
        }
      },
    },
  }),
);
proxy.listen(apiUrl.port, (err) => {
  if (err) throw err;
  console.log(`> Proxy server ready on ${API_URL}`);
});