next.config.js

const withPlugins = require("next-compose-plugins");
const withPWA = require("next-pwa");
const runtimeCaching = require("next-pwa/cache");
const withBundleAnalyzer = require("@next/bundle-analyzer")({
  enabled: process.env.ANALYZE === "true",
});

const __prod__ = process.env.NODE_ENV === "production";

const nextConfig = {
  images: {
    domains: [
      "i.scdn.co", // Spotify Album Art
    ],
  },
  reactStrictMode: true,
  async headers() {
    return [
      {
        source: "/(.*)",
        headers: securityHeaders,
      },
    ];
  },
  webpack: (config, { isServer }) => {
    if (isServer) {
      require("./scripts/generate-sitemap");
    }
    return config;
  },
};

module.exports = withPlugins(
  [
    [
      withPWA,
      {
        pwa: {
          dest: "public",
          disable: __prod__ ? false : true,
          runtimeCaching,
        },
      },
    ],
    [withBundleAnalyzer],
  ],
  nextConfig,
);

// https://securityheaders.com
const ContentSecurityPolicy = `
  default-src 'self' disqus.com c.disquscdn.com;
  script-src 'self' *.googletagmanager.com *.disqus.com c.disquscdn.com;
  child-src 'self' *.google.com;
  frame-src disqus.com;
  style-src 'self' *.googleapis.com c.disquscdn.com;
  img-src * blob: data:;
  media-src 'none';
  connect-src *;
  font-src 'self';
`;

const securityHeaders = [
  // https://developer.mozilla.org/en-US/docs/Web/HTTP/CSP
  {
    key: "Content-Security-Policy",
    value: ContentSecurityPolicy.replace(/\n/g, ""),
  },
  // https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Referrer-Policy
  {
    key: "Referrer-Policy",
    value: "strict-origin-when-cross-origin",
  },
  // https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Frame-Options
  {
    key: "X-Frame-Options",
    value: "DENY",
  },
  // https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Content-Type-Options
  {
    key: "X-Content-Type-Options",
    value: "nosniff",
  },
  // https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-DNS-Prefetch-Control
  {
    key: "X-DNS-Prefetch-Control",
    value: "on",
  },
  // https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Strict-Transport-Security
  {
    key: "Strict-Transport-Security",
    value: "max-age=31536000; includeSubDomains; preload",
  },
  // https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Feature-Policy
  // Opt-out of Google FLoC: https://amifloced.org/
  {
    key: "Permissions-Policy",
    value: "camera=(), microphone=(), geolocation=(), interest-cohort=()",
  },
];