Miro Local Dev Loop

Overview

Set up a fast local development workflow for building Miro integrations, including hot reload, test mocking against the REST API v2, and ngrok tunneling for webhooks.

Prerequisites

• Completed miro-install-auth setup
• Node.js 18+ with npm or pnpm
• Access token with boards:read and boards:write scopes
• ngrok (for webhook development)

Instructions

Step 1: Project Structure

my-miro-app/
├── src/
│   ├── miro/
│   │   ├── client.ts       # MiroApi wrapper singleton
│   │   ├── boards.ts       # Board CRUD operations
│   │   ├── items.ts        # Item operations (sticky notes, shapes, etc.)
│   │   └── types.ts        # Response type definitions
│   ├── webhooks/
│   │   └── handler.ts      # Webhook event processing
│   └── index.ts
├── tests/
│   ├── miro-client.test.ts
│   └── fixtures/
│       ├── board.json       # Sample board response
│       └── sticky-note.json # Sample item response
├── .env.local               # Local secrets (git-ignored)
├── .env.example             # Template for team
├── package.json
└── tsconfig.json

Step 2: Package Configuration

{
  "scripts": {
    "dev": "tsx watch src/index.ts",
    "test": "vitest",
    "test:watch": "vitest --watch",
    "test:integration": "MIRO_TEST_MODE=live vitest run tests/integration/",
    "tunnel": "ngrok http 3000",
    "typecheck": "tsc --noEmit"
  },
  "dependencies": {
    "@mirohq/miro-api": "^2.0.0",
    "express": "^4.18.0",
    "dotenv": "^16.0.0"
  },
  "devDependencies": {
    "tsx": "^4.0.0",
    "vitest": "^1.0.0",
    "typescript": "^5.0.0"
  }
}

Step 3: Miro Client Singleton

// src/miro/client.ts
import { MiroApi } from '@mirohq/miro-api';

let instance: MiroApi | null = null;

export function getMiroApi(): MiroApi {
  if (!instance) {
    const token = process.env.MIRO_ACCESS_TOKEN;
    if (!token) throw new Error('MIRO_ACCESS_TOKEN not set');
    instance = new MiroApi(token);
  }
  return instance;
}

// For testing — allow injecting a mock
export function resetMiroApi(): void {
  instance = null;
}

Step 4: Test Fixtures from Real API Responses

// tests/fixtures/board.json
{
  "id": "uXjVN1234567890",
  "type": "board",
  "name": "Test Board",
  "description": "Fixture for unit tests",
  "createdAt": "2025-01-15T10:00:00Z",
  "modifiedAt": "2025-01-15T10:30:00Z",
  "owner": { "id": "123456", "type": "user", "name": "Dev User" },
  "policy": {
    "sharingPolicy": { "access": "private" },
    "permissionsPolicy": { "collaborationToolsStartAccess": "all_editors" }
  }
}

// tests/fixtures/sticky-note.json
{
  "id": "3458764500000001",
  "type": "sticky_note",
  "data": { "content": "Test note", "shape": "square" },
  "style": { "fillColor": "light_yellow", "textAlign": "center" },
  "position": { "x": 100, "y": 200, "origin": "center" },
  "geometry": { "width": 199 },
  "createdAt": "2025-01-15T10:05:00Z",
  "modifiedAt": "2025-01-15T10:05:00Z",
  "createdBy": { "id": "123456", "type": "user" }
}

Step 5: Unit Tests with Vitest Mocks

// tests/miro-client.test.ts
import { describe, it, expect, vi, beforeEach } from 'vitest';
import boardFixture from './fixtures/board.json';
import stickyNoteFixture from './fixtures/sticky-note.json';

// Mock fetch for Miro API calls
const mockFetch = vi.fn();
vi.stubGlobal('fetch', mockFetch);

describe('Miro Board Operations', () => {
  beforeEach(() => {
    mockFetch.mockReset();
  });

  it('should create a sticky note on a board', async () => {
    mockFetch.mockResolvedValueOnce({
      ok: true,
      status: 201,
      json: async () => stickyNoteFixture,
    });

    const response = await fetch(
      'https://api.miro.com/v2/boards/uXjVN123/sticky_notes',
      {
        method: 'POST',
        headers: {
          'Authorization': 'Bearer test-token',
          'Content-Type': 'application/json',
        },
        body: JSON.stringify({
          data: { content: 'Test note', shape: 'square' },
          position: { x: 100, y: 200 },
        }),
      }
    );

    const note = await response.json();
    expect(note.type).toBe('sticky_note');
    expect(note.data.content).toBe('Test note');
    expect(mockFetch).toHaveBeenCalledWith(
      expect.stringContaining('/v2/boards/'),
      expect.objectContaining({ method: 'POST' })
    );
  });

  it('should handle 429 rate limit responses', async () => {
    mockFetch.mockResolvedValueOnce({
      ok: false,
      status: 429,
      headers: new Headers({
        'X-RateLimit-Remaining': '0',
        'Retry-After': '5',
      }),
      json: async () => ({ status: 429, message: 'Rate limit exceeded' }),
    });

    const response = await fetch('https://api.miro.com/v2/boards', {
      headers: { 'Authorization': 'Bearer test-token' },
    });

    expect(response.status).toBe(429);
  });
});

Step 6: Ngrok Tunneling for Webhooks

# Start your dev server
npm run dev

# In another terminal, start ngrok
ngrok http 3000

# Copy the HTTPS URL (e.g., https://abc123.ngrok.app)
# Register it as a webhook callback in your Miro app settings
# or via the API (see miro-webhooks-events skill)

Step 7: Debug Logging

// Enable verbose HTTP logging during development
import { MiroApi } from '@mirohq/miro-api';

// Log all API requests and responses
const api = new MiroApi(process.env.MIRO_ACCESS_TOKEN!, {
  logger: {
    info: (...args) => console.log('[MIRO]', ...args),
    warn: (...args) => console.warn('[MIRO]', ...args),
    error: (...args) => console.error('[MIRO]', ...args),
  },
});

Environment Variables

Error Handling

Resources

• Miro Node.js Quickstart
• Vitest Documentation
• ngrok Documentation

Next Steps

See miro-sdk-patterns for production-ready code patterns.