私有NPM代理程序

npm-proxy.js

const httpRequest = require("http").request;
const httpsRequest = require("https").request;
const parseUrl = require("url").parse;
const connect = require("connect");
const colors = require("colors");

const PORT = Number(process.env.PORT || 6666);
const REGISTRY_CDN =
  process.env.REGISTRY_CDN || "https://registry.npm.taobao.org";
const REGISTRY_PRIVATE =
  process.env.REGISTRY_PRIVATE || "https://sinopia.example.com";
const PRIVATE_AUTHTOKEN =
  process.env.PRIVATE_AUTHTOKEN ||
  "*********************";
const PACKAGE_PREFIX = process.env.PACKAGE_PREFIX || "@";

const app = connect();

app.use(function(req, res) {
  // console.log(req.url.indexOf(PACKAGE_PREFIX) === 0, req.url, PACKAGE_PREFIX);
  if (req.url.indexOf(PACKAGE_PREFIX) === 1) {
    proxy(req, res, REGISTRY_PRIVATE);
  } else {
    proxy(req, res, REGISTRY_CDN);
  }
});

console.log("CDN 地址：%s", REGISTRY_CDN);
console.log("私有地址：%s", REGISTRY_PRIVATE);
app.listen(PORT, () => console.log("监听端口：%s", PORT));

let counter = 0;
function proxy(req, res, target) {
  const n = ++counter;
  const t = Date.now();
  const log = (...args) => outputLog(n, t, ...args);

  log("%s %s  代理到：%s", req.method, req.url, target);
  // console.log(req.headers);
  const info = parseUrl(target);
  info.port = Number(info.port || (isHttpsProtocol(info.protocol) ? 443 : 80));
  const headers = { ...req.headers };
  delete headers["connection"];
  delete headers["host"];
  if (target === REGISTRY_PRIVATE) {
    // 私有 NPM 的 authtoken
    headers["authorization"] = `Bearer ${PRIVATE_AUTHTOKEN}`;
  }
  const info2 = {
    host: info.hostname,
    port: info.port,
    method: req.method,
    path: req.url,
    headers: headers
  };

  // 针对 CNPM 特殊情况
  if (info2.path === "//binary-mirror-config/latest") {
    info2.path = info2.path.slice(1);
  }
  // 针对 sinopia 特殊情况在 CNPM 上有 bug
  let hook = false;
  if (
    target === REGISTRY_PRIVATE &&
    req.method === "GET" &&
    /\/[a-zA-Z0-9\-%@]/.test(req.url)
  ) {
    delete info2.headers["accept-encoding"];
    hook = (req, res, req2, res2) => {
      log("改写 package 数据");
      delete res2.headers["content-length"];
      res.writeHead(res2.statusCode || 200, res2.headers);
      const list = [];
      res2.on("data", b => list.push(b));
      res2.on("end", () => {
        const buf = Buffer.concat(list);
        let data;
        try {
          data = JSON.parse(buf.toString());
        } catch (err) {
          log(colors.red("解析 JSON 出错：%s"), err);
          return res.end(buf);
        }
        for (const v in data.versions) {
          const vf = data.versions[v];
          if (vf && vf.dist && vf.dist.tarball) {
            // 改写为 https
            if (vf.dist.tarball.indexOf("http:") === 0) {
              vf.dist.tarball = `https:${vf.dist.tarball.slice(5)}`;
            }
            // 更换域名为本地服务器
            vf.dist.tarball = String(vf.dist.tarball).replace(
              REGISTRY_PRIVATE,
              `http://127.0.0.1:${PORT}`
            );
          }
        }
        res.end(JSON.stringify(data));
      });
    };
  }

  // log(info2);
  const request = isHttpsProtocol(info.protocol) ? httpsRequest : httpRequest;
  const req2 = request(info2, res2 => {
    const status = res2.statusCode;
    log(
      "响应：%s",
      status < 200 || status >= 400
        ? colors.yellow(status)
        : colors.green(status)
    );
    res2.on("error", err => {
      log("出错：%s", err);
      res.end(String(err));
    });

    if (hook) {
      return hook(req, res, req2, res2);
    }

    res.writeHead(res2.statusCode || 200, res2.headers);
    res2.pipe(res);
  });

  req2.on("error", err => {
    log(colors.red("出错：%s"), n, err);
  });
  req2.on("close", err => {
    log("结束");
  });

  req.pipe(req2);
}

function isHttpsProtocol(protocol) {
  protocol = protocol || "http:";
  return protocol.toLowerCase() === "https:";
}

function outputLog() {
  const args = Array.prototype.slice.call(arguments);
  const n = args[0];
  const t = args[1];
  const s = args[2];
  const a = args.slice(3);
  const x = [
    `%s %s ${s} %s`,
    colors.gray(toISOString(new Date())),
    colors.green(`[${n}]`),
    ...a,
    colors.cyan(`+${Date.now() - t}ms`)
  ];
  console.log.apply(console, x);
}

function toISOString(date) {
  function pad(n) {
    return n < 10 ? "0" + n : String(n);
  }
  return (
    date.getFullYear() +
    "-" +
    pad(date.getMonth() + 1) +
    "-" +
    pad(date.getDate()) +
    "T" +
    pad(date.getHours()) +
    ":" +
    pad(date.getMinutes()) +
    ":" +
    pad(date.getSeconds()) +
    "." +
    (date.getMilliseconds() / 1000).toFixed(3).slice(2, 5) +
    "+" +
    pad(-date.getTimezoneOffset() / 60) +
    ":00"
  );
}

// npm获取路径： https://sinopia.example.com/json5/-/json5-0.5.1.tgz
// cnpm获取路径：https://sinopia.example.com/@private%2fmodule/-/module-1.2.0.tgz
// cnpm --registry="http://127.0.0.1:6666/" i @gz/oss