dcrouter/test/suite/smtpclient_connection/test.ccm-03.starttls-upgrade.ts

import { tap, expect } from '@git.zone/tstest/tapbundle';
import { startTestServer, stopTestServer, type ITestServer } from '../../helpers/server.loader.js';
import { createSmtpClient } from '../../../ts/mail/delivery/smtpclient/index.js';
import type { SmtpClient } from '../../../ts/mail/delivery/smtpclient/smtp-client.js';
import { Email } from '../../../ts/mail/core/classes.email.js';

let testServer: ITestServer;
let smtpClient: SmtpClient;

tap.test('setup - start SMTP server with STARTTLS support', async () => {
  testServer = await startTestServer({
    port: 2528,
    tlsEnabled: true, // Enables STARTTLS capability
    authRequired: false
  });
  
  expect(testServer.port).toEqual(2528);
});

tap.test('CCM-03: STARTTLS Upgrade - should upgrade plain connection to TLS', async () => {
  const startTime = Date.now();
  
  try {
    // Create SMTP client starting with plain connection
    smtpClient = createSmtpClient({
      host: testServer.hostname,
      port: testServer.port,
      secure: false, // Start with plain connection
      connectionTimeout: 10000,
      tls: {
        rejectUnauthorized: false // For self-signed test certificates
      },
      debug: true
    });
    
    // The client should automatically upgrade to TLS via STARTTLS
    const isConnected = await smtpClient.verify();
    expect(isConnected).toBeTrue();
    
    const duration = Date.now() - startTime;
    console.log(`✅ STARTTLS upgrade completed in ${duration}ms`);
    
  } catch (error) {
    const duration = Date.now() - startTime;
    console.error(`❌ STARTTLS upgrade failed after ${duration}ms:`, error);
    throw error;
  }
});

tap.test('CCM-03: STARTTLS Upgrade - should send email after upgrade', async () => {
  const email = new Email({
    from: 'test@example.com',
    to: 'recipient@example.com',
    subject: 'STARTTLS Upgrade Test',
    text: 'This email was sent after STARTTLS upgrade',
    html: '<p>This email was sent after <strong>STARTTLS upgrade</strong></p>'
  });
  
  const result = await smtpClient.sendMail(email);
  
  expect(result.success).toBeTrue();
  expect(result.acceptedRecipients).toContain('recipient@example.com');
  expect(result.rejectedRecipients.length).toEqual(0);
  
  console.log('✅ Email sent successfully after STARTTLS upgrade');
  console.log('📧 Message ID:', result.messageId);
});

tap.test('CCM-03: STARTTLS Upgrade - should handle servers without STARTTLS', async () => {
  // Start a server without TLS support
  const plainServer = await startTestServer({
    port: 2529,
    tlsEnabled: false // No STARTTLS support
  });
  
  try {
    const plainClient = createSmtpClient({
      host: plainServer.hostname,
      port: plainServer.port,
      secure: false,
      connectionTimeout: 5000,
      debug: true
    });
    
    // Should still connect but without TLS
    const isConnected = await plainClient.verify();
    expect(isConnected).toBeTrue();
    
    // Send test email over plain connection
    const email = new Email({
      from: 'test@example.com',
      to: 'recipient@example.com',
      subject: 'Plain Connection Test',
      text: 'This email was sent over plain connection'
    });
    
    const result = await plainClient.sendMail(email);
    expect(result.success).toBeTrue();
    
    await plainClient.close();
    console.log('✅ Successfully handled server without STARTTLS');
    
  } finally {
    await stopTestServer(plainServer);
  }
});

tap.test('CCM-03: STARTTLS Upgrade - should respect TLS options during upgrade', async () => {
  const customTlsClient = createSmtpClient({
    host: testServer.hostname,
    port: testServer.port,
    secure: false, // Start plain
    connectionTimeout: 10000,
    tls: {
      rejectUnauthorized: false,
      minVersion: 'TLSv1.2',
      ciphers: 'HIGH:!aNULL:!MD5'
    }
  });
  
  const isConnected = await customTlsClient.verify();
  expect(isConnected).toBeTrue();
  
  await customTlsClient.close();
  console.log('✅ Custom TLS options applied during STARTTLS upgrade');
});

tap.test('CCM-03: STARTTLS Upgrade - should handle upgrade failures gracefully', async () => {
  // Create a mock scenario where STARTTLS might fail
  // This would typically happen with certificate issues or protocol mismatches
  
  let errorCaught = false;
  
  try {
    const strictTlsClient = createSmtpClient({
      host: testServer.hostname,
      port: testServer.port,
      secure: false,
      connectionTimeout: 5000,
      tls: {
        rejectUnauthorized: true, // Strict validation with self-signed cert
        servername: 'wrong.hostname.com' // Wrong hostname
      }
    });
    
    await strictTlsClient.verify();
    await strictTlsClient.close();
  } catch (error) {
    errorCaught = true;
    expect(error).toBeInstanceOf(Error);
    console.log('✅ STARTTLS upgrade failure handled gracefully');
  }
  
  // Should fail due to certificate validation
  expect(errorCaught).toBeTrue();
});

tap.test('CCM-03: STARTTLS Upgrade - should maintain connection state after upgrade', async () => {
  const stateClient = createSmtpClient({
    host: testServer.hostname,
    port: testServer.port,
    secure: false,
    connectionTimeout: 10000,
    tls: {
      rejectUnauthorized: false
    }
  });
  
  // Connect and verify
  await stateClient.verify();
  expect(stateClient.isConnected()).toBeTrue();
  
  // Send multiple emails to verify connection remains stable
  for (let i = 0; i < 3; i++) {
    const email = new Email({
      from: 'test@example.com',
      to: 'recipient@example.com',
      subject: `STARTTLS State Test ${i + 1}`,
      text: `Message ${i + 1} after STARTTLS upgrade`
    });
    
    const result = await stateClient.sendMail(email);
    expect(result.success).toBeTrue();
  }
  
  await stateClient.close();
  console.log('✅ Connection state maintained after STARTTLS upgrade');
});

tap.test('cleanup - close SMTP client', async () => {
  if (smtpClient && smtpClient.isConnected()) {
    await smtpClient.close();
  }
});

tap.test('cleanup - stop SMTP server', async () => {
  await stopTestServer(testServer);
});

tap.start();