正在使用的加密

const pipeline = [
  {
    $lookup: {
      from: "encryptedCollection",
      localField: "userId",
      foreignField: "_id",
      as: "userDetails"
    }
  }
];
const results = await collection.aggregate(pipeline).toArray();

import * as net from "net";
const kmsConnectCallback = ({ host, port, timeoutMS, signal }) =>
  new Promise((resolve, reject) => {
    // Opens a plain connection to the proxy, not to the KMS host.
    // Passing signal lets Node abort the connection attempt when the
    // driver's timeout budget expires.
    const socket = net.connect({
      host: "proxy.example.com",
      port: 8080,
      signal
    });
    // Applies the remaining CSOT budget to the proxy handshake, so that
    // a proxy that accepts the connection but never answers CONNECT
    // can't stall the operation.
    if (timeoutMS !== undefined) {
      socket.setTimeout(timeoutMS, () => {
        socket.destroy();
        reject(new Error("Timed out waiting for the proxy"));
      });
    }
    socket.once("error", reject);
    socket.once("connect", () => {
      // Asks the proxy to tunnel to the KMS host
      socket.write(
        `CONNECT ${host}:${port} HTTP/1.1\r\n` +
          `Host: ${host}:${port}\r\n\r\n`
      );
      socket.once("data", chunk => {
        if (chunk.toString("utf8").startsWith("HTTP/1.1 200")) {
          // Clears the handshake timeout and returns the socket so that
          // the driver can perform the TLS handshake
          socket.setTimeout(0);
          resolve(socket);
        } else {
          socket.destroy();
          reject(new Error("Proxy refused the CONNECT request"));
        }
      });
    });
  });
const clientEncryption = new ClientEncryption(keyVaultClient, {
  keyVaultNamespace,
  kmsProviders,
  kmsConnectCallback
});