Node Testing

Testing is crucial for ensuring your nodes work correctly and continue to work as the codebase evolves. n8n uses Jest for unit testing and provides testing utilities for nodes.

Testing Setup

All node tests are located in the packages/nodes-base/nodes/ directory alongside the node files.

File Naming Convention

MyNode/
├── MyNode.node.ts
├── MyNode.node.test.ts
├── GenericFunctions.ts
└── GenericFunctions.test.ts

Running Tests

cd packages/nodes-base
pnpm test

Testing Dependencies

Common testing libraries used in n8n:

import { mock } from 'jest-mock-extended';
import type {
  IExecuteFunctions,
  INodeExecutionData,
  ICredentialDataDecryptedObject,
} from 'n8n-workflow';
import { NodeOperationError } from 'n8n-workflow';
import nock from 'nock';

// Your node
import { MyNode } from './MyNode.node';

Library	Purpose
`jest`	Test framework
`jest-mock-extended`	Type-safe mocking
`nock`	HTTP mocking
`n8n-workflow`	Node interfaces and types

Basic Test Structure

Here’s a complete test file structure:

import { mock } from 'jest-mock-extended';
import type {
  IExecuteFunctions,
  INodeExecutionData,
} from 'n8n-workflow';
import { NodeOperationError } from 'n8n-workflow';

import { MyNode } from './MyNode.node';

describe('MyNode', () => {
  // Mock execution functions
  const executeFunctions = mock<IExecuteFunctions>({
    getNode: jest.fn().mockReturnValue({ name: 'MyNode Test' }),
    continueOnFail: jest.fn().mockReturnValue(false),
  });

  beforeEach(() => {
    jest.clearAllMocks();
  });

  describe('execute', () => {
    it('should execute successfully', async () => {
      // Setup
      executeFunctions.getInputData.mockReturnValue([
        { json: { test: 'data' } },
      ]);

      // Execute
      const result = await new MyNode().execute.call(executeFunctions);

      // Assert
      expect(result).toEqual([
        [{ json: { success: true }, pairedItems: { item: 0 } }],
      ]);
    });
  });
});

Mocking Execution Context

The IExecuteFunctions interface provides the context for node execution. Mock it appropriately:

Basic Mocking
Parameters
Credentials
Helpers

const executeFunctions = mock<IExecuteFunctions>({
  getNode: jest.fn().mockReturnValue({ 
    name: 'Test Node',
    type: 'n8n-nodes-base.myNode',
  }),
  continueOnFail: jest.fn().mockReturnValue(false),
  getInputData: jest.fn().mockReturnValue([
    { json: { id: 1, name: 'Test' } },
  ]),
});

// Mock getNodeParameter for different parameters
executeFunctions.getNodeParameter
  .calledWith('operation', 0)
  .mockReturnValue('create');

executeFunctions.getNodeParameter
  .calledWith('resource', 0)
  .mockReturnValue('user');

executeFunctions.getNodeParameter
  .calledWith('name', 0)
  .mockReturnValue('John Doe');

executeFunctions.getNodeParameter
  .calledWith('options', 0)
  .mockReturnValue({ timeout: 5000 });

const credentials = mock<ICredentialDataDecryptedObject>({
  apiKey: 'test-api-key',
  baseUrl: 'https://api.example.com',
});

executeFunctions.getCredentials
  .calledWith('myServiceApi')
  .mockResolvedValue(credentials);

// Mock HTTP request helper
executeFunctions.helpers.request.mockResolvedValue({
  id: 1,
  name: 'Test User',
});

// Mock returnJsonArray
executeFunctions.helpers.returnJsonArray.mockImplementation(
  (data) => data.map((item) => ({ json: item }))
);

HTTP Mocking with Nock

Use nock to mock external API calls:

import nock from 'nock';

describe('API Tests', () => {
  beforeEach(() => {
    nock.cleanAll();
  });

  it('should fetch users', async () => {
    // Mock the API response
    nock('https://api.example.com')
      .get('/users')
      .reply(200, [
        { id: 1, name: 'User 1' },
        { id: 2, name: 'User 2' },
      ]);

    // Execute node
    const result = await new MyNode().execute.call(executeFunctions);

    // Assert
    expect(result[0]).toHaveLength(2);
    expect(result[0][0].json.name).toBe('User 1');
  });
});

Real-World Example: AMQP Tests

Here’s the complete AMQP node test from the source code:

import { mock } from 'jest-mock-extended';
import type {
  ICredentialDataDecryptedObject,
  IExecuteFunctions,
  ICredentialTestFunctions,
  ICredentialsDecrypted,
} from 'n8n-workflow';
import { NodeOperationError } from 'n8n-workflow';

import { Amqp } from './Amqp.node';

// Mock the entire rhea module
const mockSender = {
  close: jest.fn(),
  send: jest.fn().mockReturnValue({ id: 'test-message-id' }),
};

const mockConnection = {
  close: jest.fn(),
  open_sender: jest.fn().mockReturnValue(mockSender),
  options: { reconnect: true },
};

const mockContainer = {
  connect: jest.fn().mockReturnValue(mockConnection),
  on: jest.fn(),
  once: jest.fn(),
};

jest.mock('rhea', () => ({
  create_container: jest.fn(() => mockContainer),
}));

describe('AMQP Node', () => {
  const credentials = mock<ICredentialDataDecryptedObject>({
    hostname: 'localhost',
    port: 5672,
    username: 'testuser',
    password: 'testpass',
    transportType: 'tcp',
  });

  const executeFunctions = mock<IExecuteFunctions>({
    getNode: jest.fn().mockReturnValue({ name: 'AMQP Test Node' }),
    continueOnFail: jest.fn().mockReturnValue(false),
  });

  beforeEach(() => {
    jest.clearAllMocks();

    executeFunctions.getCredentials
      .calledWith('amqp')
      .mockResolvedValue(credentials);
    
    executeFunctions.getInputData.mockReturnValue([
      { json: { testing: true } },
    ]);
    
    executeFunctions.getNodeParameter
      .calledWith('sink', 0)
      .mockReturnValue('test/queue');
    
    executeFunctions.getNodeParameter
      .calledWith('headerParametersJson', 0)
      .mockReturnValue({});
    
    executeFunctions.getNodeParameter
      .calledWith('options', 0)
      .mockReturnValue({});

    // Setup container event mocking
    mockContainer.once.mockImplementation((event: string, callback: any) => {
      if (event === 'sendable') {
        callback({ sender: mockSender });
      }
    });
  });

  it('should throw error when sink is empty', async () => {
    executeFunctions.getNodeParameter
      .calledWith('sink', 0)
      .mockReturnValue('');

    await expect(new Amqp().execute.call(executeFunctions)).rejects.toThrow(
      new NodeOperationError(
        executeFunctions.getNode(),
        'Queue or Topic required!'
      ),
    );
  });

  it('should send message successfully', async () => {
    const result = await new Amqp().execute.call(executeFunctions);

    expect(result).toEqual([
      [{ json: { id: 'test-message-id' }, pairedItems: { item: 0 } }],
    ]);
    expect(executeFunctions.getCredentials).toHaveBeenCalledWith('amqp');
    expect(mockContainer.connect).toHaveBeenCalled();
    expect(mockConnection.open_sender).toHaveBeenCalledWith('test/queue');
    expect(mockSender.send).toHaveBeenCalledWith({
      application_properties: {},
      body: '{"testing":true}',
    });
    expect(mockSender.close).toHaveBeenCalled();
    expect(mockConnection.close).toHaveBeenCalled();
  });

  it('should handle multiple input items', async () => {
    executeFunctions.getInputData.mockReturnValue([
      { json: { item: 1 } },
      { json: { item: 2 } },
    ]);

    const result = await new Amqp().execute.call(executeFunctions);

    expect(result).toEqual([
      [
        { json: { id: 'test-message-id' }, pairedItems: { item: 0 } },
        { json: { id: 'test-message-id' }, pairedItems: { item: 1 } },
      ],
    ]);
    expect(mockSender.send).toHaveBeenCalledTimes(2);
  });

  it('should continue on fail when configured', async () => {
    executeFunctions.continueOnFail.mockReturnValue(true);
    executeFunctions.getNodeParameter
      .calledWith('sink', 0)
      .mockReturnValue('');

    const result = await new Amqp().execute.call(executeFunctions);

    expect(result).toEqual([
      [{ json: { error: 'Queue or Topic required!' }, pairedItems: { item: 0 } }],
    ]);
  });

  describe('credential test', () => {
    it('should return success for valid credentials', async () => {
      const amqp = new Amqp();
      const testFunctions = mock<ICredentialTestFunctions>();

      mockContainer.on.mockImplementation((event: string, callback: any) => {
        if (event === 'connection_open') {
          setImmediate(() => callback({}));
        }
      });

      const result = await amqp.methods.credentialTest.amqpConnectionTest.call(
        testFunctions,
        {
          data: credentials,
          id: 'test',
          name: 'test',
          type: 'amqp',
        } as ICredentialsDecrypted,
      );

      expect(result).toEqual({
        status: 'OK',
        message: 'Connection successful!',
      });
    });

    it('should return error for invalid credentials', async () => {
      const amqp = new Amqp();
      const testFunctions = mock<ICredentialTestFunctions>();

      mockContainer.on.mockImplementation((event: string, callback: any) => {
        if (event === 'disconnected') {
          setImmediate(() => 
            callback({ error: new Error('Authentication failed') })
          );
        }
      });

      const result = await amqp.methods.credentialTest.amqpConnectionTest.call(
        testFunctions,
        {
          data: credentials,
          id: 'test',
          name: 'test',
          type: 'amqp',
        } as ICredentialsDecrypted,
      );

      expect(result).toEqual({
        status: 'Error',
        message: 'Authentication failed',
      });
    });
  });
});

Testing Patterns

Test Operations

Test Happy Path

Test the expected successful execution:

it('should create user successfully', async () => {
  executeFunctions.getNodeParameter
    .calledWith('operation', 0)
    .mockReturnValue('create');

  nock('https://api.example.com')
    .post('/users')
    .reply(201, { id: 1, name: 'New User' });

  const result = await new MyNode().execute.call(executeFunctions);

  expect(result[0][0].json).toMatchObject({ id: 1, name: 'New User' });
});

Test Error Handling

Test how the node handles errors:

it('should throw error on API failure', async () => {
  nock('https://api.example.com')
    .post('/users')
    .reply(400, { error: 'Invalid data' });

  await expect(
    new MyNode().execute.call(executeFunctions)
  ).rejects.toThrow();
});

Test Edge Cases

Test boundary conditions:

it('should handle empty input', async () => {
  executeFunctions.getInputData.mockReturnValue([]);

  const result = await new MyNode().execute.call(executeFunctions);

  expect(result).toEqual([[]]);
});

it('should handle missing parameters', async () => {
  executeFunctions.getNodeParameter
    .calledWith('userId', 0)
    .mockReturnValue('');

  await expect(
    new MyNode().execute.call(executeFunctions)
  ).rejects.toThrow('User ID is required');
});

Test Continue on Fail

Test error handling with continueOnFail:

it('should continue on fail when configured', async () => {
  executeFunctions.continueOnFail.mockReturnValue(true);

  nock('https://api.example.com')
    .post('/users')
    .reply(400, { error: 'Bad request' });

  const result = await new MyNode().execute.call(executeFunctions);

  expect(result[0][0].json).toMatchObject({
    error: expect.stringContaining('Bad request'),
  });
});

Test Binary Data

it('should handle binary data', async () => {
  executeFunctions.getInputData.mockReturnValue([
    {
      json: {},
      binary: {
        data: {
          data: Buffer.from('test data'),
          mimeType: 'text/plain',
          fileName: 'test.txt',
        },
      },
    },
  ]);

  const result = await new MyNode().execute.call(executeFunctions);

  expect(result[0][0].binary).toBeDefined();
});

Test Pagination

it('should handle pagination', async () => {
  // First page
  nock('https://api.example.com')
    .get('/users')
    .query({ page: 1 })
    .reply(200, {
      data: [{ id: 1 }, { id: 2 }],
      nextPage: 2,
    });

  // Second page
  nock('https://api.example.com')
    .get('/users')
    .query({ page: 2 })
    .reply(200, {
      data: [{ id: 3 }, { id: 4 }],
      nextPage: null,
    });

  executeFunctions.getNodeParameter
    .calledWith('returnAll', 0)
    .mockReturnValue(true);

  const result = await new MyNode().execute.call(executeFunctions);

  expect(result[0]).toHaveLength(4);
});

Testing LoadOptions

import type { ILoadOptionsFunctions } from 'n8n-workflow';

describe('loadOptions', () => {
  const loadOptionsFunctions = mock<ILoadOptionsFunctions>();

  beforeEach(() => {
    jest.clearAllMocks();
    
    loadOptionsFunctions.getCredentials
      .calledWith('myServiceApi')
      .mockResolvedValue({ apiKey: 'test-key' });
  });

  it('should load users', async () => {
    nock('https://api.example.com')
      .get('/users')
      .reply(200, [
        { id: '1', name: 'User 1' },
        { id: '2', name: 'User 2' },
      ]);

    const node = new MyNode();
    const result = await node.methods.loadOptions.getUsers.call(
      loadOptionsFunctions,
    );

    expect(result).toEqual([
      { name: 'User 1', value: '1' },
      { name: 'User 2', value: '2' },
    ]);
  });
});

Testing Credential Tests

import type { ICredentialTestFunctions } from 'n8n-workflow';

describe('credentialTest', () => {
  const credentialTestFunctions = mock<ICredentialTestFunctions>();

  it('should validate correct credentials', async () => {
    nock('https://api.example.com')
      .get('/auth/verify')
      .reply(200, { status: 'ok' });

    const node = new MyNode();
    const result = await node.methods.credentialTest.testApiCredentials.call(
      credentialTestFunctions,
      {
        data: { apiKey: 'valid-key' },
        id: 'test',
        name: 'test',
        type: 'myServiceApi',
      } as ICredentialsDecrypted,
    );

    expect(result).toEqual({
      status: 'OK',
      message: 'Authentication successful',
    });
  });

  it('should reject invalid credentials', async () => {
    nock('https://api.example.com')
      .get('/auth/verify')
      .reply(401);

    const node = new MyNode();
    const result = await node.methods.credentialTest.testApiCredentials.call(
      credentialTestFunctions,
      {
        data: { apiKey: 'invalid-key' },
        id: 'test',
        name: 'test',
        type: 'myServiceApi',
      } as ICredentialsDecrypted,
    );

    expect(result.status).toBe('Error');
  });
});

Best Practices

Follow these testing best practices for maintainable tests.

DO:

✅ Mock all external dependencies
✅ Test happy paths, error cases, and edge cases
✅ Use jest.clearAllMocks() in beforeEach()
✅ Use nock.cleanAll() when testing HTTP requests
✅ Test credential validation
✅ Test continue-on-fail behavior
✅ Use descriptive test names
✅ Test with multiple items
✅ Test binary data handling

DON’T:

❌ Make real API calls in tests
❌ Use any type in test code
❌ Share state between tests
❌ Test implementation details
❌ Skip error case testing
❌ Hardcode test data in multiple places

Coverage Requirements

Aim for high test coverage:

Statements: > 80%
Branches: > 75%
Functions: > 80%
Lines: > 80%

Check coverage:

cd packages/nodes-base
pnpm test -- --coverage

Getting Started

Self-Hosting

Building Workflows

AI Workflows

Node Development

CLI Reference

Node Testing

Node Testing

Testing Setup

File Naming Convention

Running Tests

Testing Dependencies

Basic Test Structure

Mocking Execution Context

HTTP Mocking with Nock

Real-World Example: AMQP Tests

Testing Patterns

Test Operations

Test Binary Data

Testing LoadOptions

Testing Credential Tests

Best Practices

DO:

DON’T:

Coverage Requirements

Next Steps

Versioning

Node Structure

Getting Started

Self-Hosting

Building Workflows

AI Workflows

Node Development

CLI Reference

​Node Testing

​Testing Setup

​File Naming Convention

​Running Tests

​Testing Dependencies

​Basic Test Structure

​Mocking Execution Context

​HTTP Mocking with Nock

​Real-World Example: AMQP Tests

​Testing Patterns

​Test Operations

​Test Binary Data

​Test Pagination

​Testing LoadOptions

​Testing Credential Tests

​Best Practices

​DO:

​DON’T:

​Coverage Requirements

​Next Steps

Versioning

Node Structure

Node Testing

Testing Setup

File Naming Convention

Running Tests

Testing Dependencies

Basic Test Structure

Mocking Execution Context

HTTP Mocking with Nock

Real-World Example: AMQP Tests

Testing Patterns

Test Operations

Test Binary Data

Test Pagination

Testing LoadOptions

Testing Credential Tests

Best Practices

DO:

DON’T:

Coverage Requirements

Next Steps