@redocly/cli/src/commands/preview-docs/preview-server/server.ts

[@Redocly](https://redocly.com) CLI is your all-in-one OpenAPI utility. It builds, manages, improves, and quality-checks your OpenAPI descriptions, all of which comes in handy for various phases of the API Lifecycle. Create your own rulesets to make API g

import * as http from 'http';
import * as zlib from 'zlib';

import type { ReadStream } from 'fs';

const SocketServer = require('simple-websocket/server.js');

export const mimeTypes = {
  '.html': 'text/html',
  '.js': 'text/javascript',
  '.css': 'text/css',
  '.json': 'application/json',
  '.png': 'image/png',
  '.jpg': 'image/jpg',
  '.gif': 'image/gif',
  '.svg': 'image/svg+xml',
  '.wav': 'audio/wav',
  '.mp4': 'video/mp4',
  '.woff': 'application/font-woff',
  '.ttf': 'application/font-ttf',
  '.eot': 'application/vnd.ms-fontobject',
  '.otf': 'application/font-otf',
  '.wasm': 'application/wasm',
};

// credits: https://stackoverflow.com/a/9238214/1749888
export function respondWithGzip(
  contents: string | Buffer | ReadStream,
  request: http.IncomingMessage,
  response: http.ServerResponse,
  headers = {},
  code = 200
) {
  let compressedStream;
  const acceptEncoding = (request.headers['accept-encoding'] as string) || '';
  if (acceptEncoding.match(/\bdeflate\b/)) {
    response.writeHead(code, { ...headers, 'content-encoding': 'deflate' });
    compressedStream = zlib.createDeflate();
  } else if (acceptEncoding.match(/\bgzip\b/)) {
    response.writeHead(code, { ...headers, 'content-encoding': 'gzip' });
    compressedStream = zlib.createGzip();
  } else {
    response.writeHead(code, headers);
    if (typeof contents === 'string' || Buffer.isBuffer(contents)) {
      response.write(contents);
      response.end();
    } else if (response !== undefined) {
      contents.pipe(response);
    }
    return;
  }

  if (typeof contents === 'string' || Buffer.isBuffer(contents)) {
    compressedStream.write(contents);
    compressedStream.pipe(response);
    compressedStream.end();
  } else {
    contents.pipe(compressedStream).pipe(response);
  }
}

export function startHttpServer(port: number, host: string, handler: http.RequestListener) {
  return http.createServer(handler).listen(port, host);
}

export function startWsServer(port: number, host: string) {
  const socketServer = new SocketServer({ port, host, clientTracking: true });

  socketServer.on('connection', (socket: any) => {
    socket.on('data', (data: string) => {
      const message = JSON.parse(data);
      switch (message.type) {
        case 'ping':
          socket.send('{"type": "pong"}');
          break;
        default:
        // nope
      }
    });
  });

  socketServer.broadcast = (message: string) => {
    socketServer._server.clients.forEach((client: any) => {
      if (client.readyState === 1) {
        // OPEN
        client.send(message);
      }
    });
  };

  return socketServer;
}