mxrelay-consumer/tests/transport.test.ts

import nodemailer from 'nodemailer';
import { SMTPWSTransport, createTransport } from '../src/transport';

describe('SMTPWSTransport', () => {
  let transport: SMTPWSTransport;

  beforeEach(() => {
    transport = createTransport({
      host: 'localhost',
      port: 3000,
      auth: {
        user: 'test-api-key'
      },
      debug: false
    });
  });

  afterEach(async () => {
    await transport.close();
  });

  describe('constructor', () => {
    it('should create transport with correct configuration', () => {
      expect(transport.name).toBe('SMTPWS');
      expect(transport.version).toBe('1.0.0');
    });

    it('should handle secure connection configuration', () => {
      const secureTransport = createTransport({
        host: 'localhost',
        port: 443,
        secure: true,
        auth: {
          user: 'test-key'
        },
        debug: false
      });

      const info = secureTransport.getTransportInfo();
      expect(info.secure).toBe(true);
      expect(info.port).toBe(443);
    });
  });

  describe('getTransportInfo', () => {
    it('should return transport information', () => {
      const info = transport.getTransportInfo();
      
      expect(info).toMatchObject({
        name: 'SMTPWS',
        version: '1.0.0',
        host: 'localhost',
        port: 3000,
        secure: false
      });
    });
  });

  describe('send', () => {
    it('should send mail message', async () => {
      const mockMail = {
        data: {
          envelope: {
            from: 'test@example.com',
            to: ['recipient@example.com']
          },
          raw: 'Subject: Test\r\n\r\nTest message'
        }
      };

      // Mock the internal client
      const mockSendCommand = jest.fn()
        .mockResolvedValueOnce('250 Hello')  // EHLO
        .mockResolvedValueOnce('250 OK')     // MAIL FROM
        .mockResolvedValueOnce('250 OK')     // RCPT TO
        .mockResolvedValueOnce('354 Start mail input') // DATA
        .mockResolvedValueOnce('250 Message accepted')  // Message content
        .mockResolvedValueOnce('221 Bye');   // QUIT

      (transport as any).client.sendSMTPCommand = mockSendCommand;

      const result = await transport.send(mockMail);

      expect(result).toMatchObject({
        envelope: mockMail.data.envelope,
        accepted: ['recipient@example.com'],
        rejected: [],
        pending: []
      });

      expect(mockSendCommand).toHaveBeenCalledTimes(6);
    });

    it('should handle rejected recipients', async () => {
      const mockMail = {
        data: {
          envelope: {
            from: 'test@example.com',
            to: ['good@example.com', 'bad@example.com']
          },
          raw: 'Subject: Test\r\n\r\nTest message'
        }
      };

      const mockSendCommand = jest.fn()
        .mockResolvedValueOnce('250 Hello')  // EHLO
        .mockResolvedValueOnce('250 OK')     // MAIL FROM
        .mockResolvedValueOnce('250 OK')     // RCPT TO (good)
        .mockResolvedValueOnce('550 No such user') // RCPT TO (bad)
        .mockResolvedValueOnce('354 Start mail input') // DATA
        .mockResolvedValueOnce('250 Message accepted')  // Message content
        .mockResolvedValueOnce('221 Bye');   // QUIT

      (transport as any).client.sendSMTPCommand = mockSendCommand;

      const result = await transport.send(mockMail);

      expect(result.accepted).toEqual(['good@example.com']);
      expect(result.rejected).toEqual(['bad@example.com']);
    });

    it('should call callback on success', (done) => {
      const mockMail = {
        data: {
          envelope: {
            from: 'test@example.com',
            to: ['recipient@example.com']
          },
          raw: 'Test message'
        }
      };

      const mockSendCommand = jest.fn()
        .mockResolvedValueOnce('250 Hello')
        .mockResolvedValueOnce('250 OK')
        .mockResolvedValueOnce('250 OK')
        .mockResolvedValueOnce('354 Start mail input')
        .mockResolvedValueOnce('250 Message accepted')
        .mockResolvedValueOnce('221 Bye');

      (transport as any).client.sendSMTPCommand = mockSendCommand;

      transport.send(mockMail, (err, info) => {
        expect(err).toBeNull();
        expect(info).toBeDefined();
        expect(info?.accepted).toEqual(['recipient@example.com']);
        done();
      });
    });

    it('should call callback on error', (done) => {
      const mockMail = {
        envelope: {
          from: 'test@example.com',
          to: ['recipient@example.com']
        },
        raw: 'Test message'
      };

      const mockSendCommand = jest.fn()
        .mockRejectedValueOnce(new Error('Connection failed'));

      (transport as any).client.sendSMTPCommand = mockSendCommand;

      transport.send(mockMail, (err, info) => {
        expect(err).toBeDefined();
        expect(err?.message).toBe('Connection failed');
        expect(info).toBeUndefined();
        done();
      });
    });
  });

  describe('verify', () => {
    it('should verify transport connectivity', async () => {
      const mockSendCommand = jest.fn()
        .mockResolvedValueOnce('250 Hello');

      (transport as any).client.sendSMTPCommand = mockSendCommand;

      const result = await transport.verify();
      expect(result).toBe(true);
      expect(mockSendCommand).toHaveBeenCalledWith('EHLO transport-verify\r\n');
    });

    it('should throw error on verification failure', async () => {
      const mockSendCommand = jest.fn()
        .mockRejectedValueOnce(new Error('Connection refused'));

      (transport as any).client.sendSMTPCommand = mockSendCommand;

      await expect(transport.verify()).rejects.toThrow('Transport verification failed');
    });

    it('should throw error on missing API key during construction', async () => {
      expect(() => createTransport({
        host: 'localhost',
        auth: { user: '' },
        debug: false
      })).toThrow('API key is required');
    });
  });

  describe('isIdle', () => {
    it('should return true when transport is idle', () => {
      expect(transport.isIdle()).toBe(true);
    });

    it('should return false when transport has queued messages', () => {
      // Mock queue size
      (transport as any).client.getQueueSize = jest.fn().mockReturnValue(5);
      
      expect(transport.isIdle()).toBe(false);
    });
  });

  describe('nodemailer integration', () => {
    it('should work as nodemailer transport', async () => {
      const transporter = nodemailer.createTransport(transport);
      expect(transporter).toBeDefined();
    });
  });
});