router-lists-ui/backend/routes/evobgpProxyRoutes.js

const http = require('http');
const https = require('https');
const { URL } = require('url');

/**
 * Нормализует базовый URL API EvoBGP до вида …/v1 (без завершающего слэша).
 */
function normalizeEvobgpBaseUrl(raw) {
  if (!raw || !String(raw).trim()) return '';
  const input = String(raw).trim();
  try {
    const u = new URL(input);
    let path = (u.pathname || '').replace(/\/+$/, '');
    if (!path || path === '/') {
      u.pathname = '/v1';
    } else if (!/\/v1$/i.test(path)) {
      u.pathname = `${path}/v1`;
    } else {
      u.pathname = path;
    }
    return `${u.origin}${u.pathname}`.replace(/\/+$/, '');
  } catch {
    return '';
  }
}

/**
 * Прокси EvoBGP: браузер бьёт в тот же origin (/api/evobgp/…), сервер добавляет Bearer и ходит в EvoBGP по сети Docker (без CORS).
 */
function createEvobgpProxy({ logger = console } = {}) {
  return function evobgpProxy(req, res) {
    const base = normalizeEvobgpBaseUrl(process.env.EVOBGP_API_URL || '');
    const token = String(process.env.EVOBGP_API_TOKEN || '').trim();

    if (!base) {
      return res.status(503).json({
        code: 'E_EVOBGP_PROXY_NOT_CONFIGURED',
        message:
          'Прокси EvoBGP не настроен: задайте EVOBGP_API_URL (и при необходимости EVOBGP_API_TOKEN) в окружении контейнера.',
      });
    }
    if (!token) {
      return res.status(503).json({
        code: 'E_EVOBGP_PROXY_NO_TOKEN',
        message: 'Прокси EvoBGP: не задан EVOBGP_API_TOKEN в окружении сервера.',
      });
    }

    const suffix = req.url && req.url.length ? req.url : '/';
    const targetUrl = `${base}${suffix.startsWith('/') ? suffix : `/${suffix}`}`;

    let parsed;
    try {
      parsed = new URL(targetUrl);
    } catch {
      return res.status(500).json({
        code: 'E_EVOBGP_PROXY_BAD_URL',
        message: 'Некорректный EVOBGP_API_URL',
      });
    }

    const lib = parsed.protocol === 'https:' ? https : http;
    const headers = { ...req.headers };
    delete headers.host;
    delete headers.connection;
    delete headers['content-length'];
    delete headers.cookie;
    headers.authorization = `Bearer ${token}`;
    headers.host = parsed.host;

    const opts = {
      hostname: parsed.hostname,
      port: parsed.port || (parsed.protocol === 'https:' ? 443 : 80),
      path: parsed.pathname + parsed.search,
      method: req.method,
      headers,
      timeout: Math.min(120000, Number(process.env.EVOBGP_PROXY_TIMEOUT_MS) || 60000),
    };

    const clientReq = lib.request(opts, (clientRes) => {
      res.status(clientRes.statusCode);
      const skip = new Set(['connection', 'transfer-encoding', 'content-encoding']);
      Object.keys(clientRes.headers).forEach((k) => {
        if (!skip.has(k.toLowerCase())) {
          res.setHeader(k, clientRes.headers[k]);
        }
      });
      clientRes.pipe(res);
    });

    clientReq.on('error', (err) => {
      try {
        (req.log || logger).error({ err: err.message, target: targetUrl }, 'evobgp proxy');
      } catch {
        /* no-op */
      }
      if (!res.headersSent) {
        res.status(502).json({
          code: 'E_EVOBGP_PROXY_UPSTREAM',
          message: err.message || 'Не удалось связаться с EvoBGP',
        });
      }
    });

    clientReq.on('timeout', () => {
      clientReq.destroy();
      if (!res.headersSent) {
        res.status(504).json({
          code: 'E_EVOBGP_PROXY_TIMEOUT',
          message: 'Таймаут запроса к EvoBGP',
        });
      }
    });

    if (req.method === 'OPTIONS' || req.method === 'GET' || req.method === 'HEAD') {
      clientReq.end();
      return;
    }

    if (req.method === 'DELETE') {
      clientReq.end();
      return;
    }

    const body =
      req.body !== undefined && req.body !== null && typeof req.body === 'object'
        ? JSON.stringify(req.body)
        : typeof req.body === 'string'
          ? req.body
          : '';

    if (body) {
      const buf = Buffer.from(body, 'utf8');
      clientReq.setHeader('Content-Type', req.headers['content-type'] || 'application/json');
      clientReq.setHeader('Content-Length', buf.length);
      clientReq.end(buf);
    } else {
      clientReq.end();
    }
  };
}

module.exports = {
  createEvobgpProxy,
  normalizeEvobgpBaseUrl,
};