Sample IAM Authentication for Oracle Autonomous Database using node-oracledb

iamTokenAuthentication.js

const fs = require('fs');
const oracledb = require('oracledb');
const { execSync } = require('child_process');

let accessTokenObj;

// Execute the OCI-CLI command to generate a token.
// Requires Python to be installed to run OCI-CLI
// This should create two files "token" and "oci_db_key.pem".
// On Linux the default file location is "~/.oci/db-token".
try {
  const cmdResult = execSync('oci iam db-token get', { encoding: 'utf-8' });
  console.log(cmdResult);
} catch (err) {
  console.log(err);
}

// User defined function for reading token and private key values generated by
// the OCI-CLI.
function getToken() {
  // Set the IAM Token and private key path here
  const tokenPath = '/home/user_name/.oci/db-token/token';
  const privateKeyPath = '/home/user_name/.oci/db-token/oci_db_key.pem';

  let token = '';
  let privateKey = '';
  try {
    // Read token file
    token = fs.readFileSync(tokenPath, 'utf8');
    // Read private key file
    const privateKeyFileContents = fs.readFileSync(privateKeyPath, 'utf-8');
    privateKeyFileContents.split(/\r?\n/).forEach(line => {
      if (line != '-----BEGIN PRIVATE KEY-----' &&
        line != '-----END PRIVATE KEY-----')
        privateKey = privateKey.concat(line);
    });
  } catch (err) {
    console.error(err);
  }

  const tokenBasedAuthData = {
    token: token,
    privateKey: privateKey
  };
  return tokenBasedAuthData;
}

function callback(refresh) {
  if (!refresh) {
    // read from cache or generate new tokens
    return accessTokenObj;
  }

  // refresh=true indicates that token is checked for expiry by driver
  // token is expired
  accessTokenObj =  getToken();
  return accessTokenObj;
}

async function run() {
  let connection;
  // Get token and private key.
  accessTokenObj = getToken();

  // Configuration for token based authentication:
  //   accessToken:    The token values
  //   externalAuth:   Must be set to true for token based authentication.
  //   connectString:  set to the Oracle Net alias or connect descriptor of
  //                   your Oracle Autonomous Database.
  //   walletPassword: set to the Wallet password of your Oracle Autonomous
  //                   Database. This is required if you are using mTLS to
  //                   connect to the Autonomous Database and not using an
  //                   auto-login wallet.
  const config = {
    accessToken: callback,
    externalAuth: true,
    connectString: "db_connectstring",
    walletPassword: "walletPassword"
  };

  try {
    connection = await oracledb.getConnection(config);
    const sql = `SELECT TO_CHAR(current_date, 'DD-Mon-YYYY HH24:MI') AS D
                 FROM DUAL`;
    const result = await connection.execute(sql);
    console.log("Current date and time is:\n", result.rows[0][0]);
  } catch (err) {
    console.error(err);
  } finally {
    try {
      if (connection)
        await connection.close();
    } catch (err) {
      console.error(err.message);
    }
  }
}

run();