git checkout basic-example

npm install

npm run build

npm start

🚀 NestJS MCP Server running on http://localhost:3000
📡 MCP Endpoint: http://localhost:3000/mcp

node test-client.mjs

GITHUB_APP_ID=your_app_id
GITHUB_INSTALLATION_ID=your_installation_id
GITHUB_PRIVATE_KEY_PATH=path/to/private-key.pem
# または
GITHUB_PRIVATE_KEY="-----BEGIN RSA PRIVATE KEY-----\n..."

src/
├── main.ts                          # エントリーポイント
├── app.module.ts                    # ルートモジュール
├── mcp/                             # MCPモジュール
│   ├── mcp.module.ts               # MCP設定・プロバイダー登録
│   ├── tools/                       # ツール層（MCPインターフェース）
│   │   ├── time.tool.ts            # 時刻ツール
│   │   ├── calculator.tool.ts      # 計算ツール
│   │   └── notes.tool.ts           # メモツール
│   └── services/                    # サービス層（ビジネスロジック）
│       ├── time.service.ts
│       ├── calculator.service.ts
│       └── notes.service.ts
└── domain/                          # ドメイン層（将来の拡張用）
    └── notes/
        └── (エンティティ、リポジトリなど)

src/
└── mcp/
    ├── tools/
    │   └── four-keys/               # Four Keysツール層
    │       ├── deployment-frequency.tool.ts
    │       ├── lead-time.tool.ts
    │       ├── change-failure-rate.tool.ts
    │       ├── mttr.tool.ts
    │       └── summary.tool.ts
    ├── services/
    │   ├── github/                  # GitHub統合サービス
    │   │   ├── github-auth.service.ts    # GitHub App認証
    │   │   └── github-api.service.ts     # GitHub API クライアント
    │   └── four-keys/               # Four Keys計算サービス
    │       ├── deployment-frequency.service.ts
    │       ├── lead-time.service.ts
    │       ├── change-failure-rate.service.ts
    │       └── mttr.service.ts
    └── types/
        ├── github.types.ts          # GitHub API型定義
        └── four-keys.types.ts       # Four Keys型定義

// src/mcp/tools/time.tool.ts
import { Injectable } from '@nestjs/common';
import { Tool } from '@rekog/mcp-nest';
import { z } from 'zod';
import { TimeService } from '../services/time.service';

@Injectable()
export class TimeTool {
  constructor(private readonly timeService: TimeService) {}

  @Tool({
    name: 'get_current_time',
    description: '現在の日時を取得します',
    parameters: z.object({}),
  })
  async getCurrentTime() {
    const time = this.timeService.getCurrentTime();
    return `現在の日時: ${time}`;
  }
}

// src/mcp/services/time.service.ts
import { Injectable } from '@nestjs/common';

@Injectable()
export class TimeService {
  getCurrentTime(): string {
    const now = new Date();
    return now.toLocaleString('ja-JP', { timeZone: 'Asia/Tokyo' });
  }
}

// src/mcp/mcp.module.ts
import { Module } from '@nestjs/common';
import { TimeService } from './services/time.service';
import { TimeTool } from './tools/time.tool';

@Module({
  providers: [
    // サービス層
    TimeService,
    // ツール層
    TimeTool,
  ],
})
export class McpToolsModule {}

npm run start:dev

npm run build

constructor(private readonly timeService: TimeService) {}

parameters: z.object({
  operation: z.enum(['add', 'subtract', 'multiply', 'divide']),
  a: z.number(),
  b: z.number(),
})

McpModule.forRoot({
  name: 'nestjs-mcp-server',
  version: '1.0.0',
  transport: McpTransportType.STREAMABLE_HTTP,
  mcpEndpoint: '/mcp',
})

@Injectable()
export class GitHubApiService {
  private octokit: Octokit | null = null;

  constructor(private readonly authService: GitHubAuthService) {}

  async listReleases(owner: string, repo: string) {
    const client = await this.getClient();
    const { data } = await client.rest.repos.listReleases({ owner, repo });
    return data;
  }
}

// Vitestを使用したモックベースのテスト
describe('DeploymentFrequencyService', () => {
  let service: DeploymentFrequencyService;
  let mockGitHubApiService: any;

  beforeEach(() => {
    vi.clearAllMocks();
    mockGitHubApiService = {
      listReleases: vi.fn().mockResolvedValue(mockReleases),
    };
    service = new DeploymentFrequencyService(mockGitHubApiService as any);
  });

  it('リリースベースでデプロイを検出できる', async () => {
    const result = await service.calculate('owner', 'repo', 'week', {
      method: 'release',
    });
    expect(result.totalDeployments).toBe(2);
  });
});

@Injectable()
export class GitHubAuthService {
  async getInstallationToken(): Promise<string> {
    const auth = createAppAuth({
      appId: this.config.appId,
      privateKey: this.config.privateKey,
      installationId: this.config.installationId,
    });

    const { token } = await auth({ type: 'installation' });
    return token;
  }
}

// TypeORM
@Module({
  imports: [
    TypeOrmModule.forRoot({...}),
    TypeOrmModule.forFeature([Note]),
  ],
})

// Prisma
@Injectable()
export class NotesService {
  constructor(private prisma: PrismaService) {}
}

@Module({
  imports: [HttpModule],
})

@Injectable()
export class ExternalApiService {
  constructor(private http: HttpService) {}
}

@Tool({...})
@UseGuards(AuthGuard)
async protectedTool() {...}