@syncafricabs/kernspark-nitro

Nitro adapter for the SyncAfrica KernSpark ecosystem. This package provides production-ready Nitro route handlers, error handlers, and response utilities that integrate the framework-independent @syncafricabs/kernspark-core with Nitro.

Table of Contents

• What is it?
• Why it exists
• Features
• Installation
• Quick Start
• Comprehensive Usage
  • Route Handlers
  • Error Handling
  • Response Adapter
  • With Error Handling Wrapper
• API Reference
• Error Handling Reference
• TypeScript Support
• Compatibility Matrix
• Contributing
• License
• Author

What is it?

@syncafricabs/kernspark-nitro is a framework adapter that bridges the SyncAfrica KernSpark Core with Nitro. It provides:

• NitroIntegration - Maps ApplicationError instances to standardized JSON API responses
• NitroResponseAdapter - Helper methods for sending consistent success and error responses
• withNitroErrorHandling - Higher-order function for wrapping route handlers with error handling

The adapter follows the adapter pattern: it depends on @syncafricabs/kernspark-core (the framework-independent layer) and Nitro only in the adapter layer. The core has zero framework dependencies.

Why it exists

Modern web applications benefit from a KernSpark - a common set of contracts, types, and behaviors shared across bounded contexts. The SyncAfrica KernSpark provides:

1. Standardized API envelopes (ApiSuccess / ApiError)
2. Rich domain error hierarchy (ValidationError, BusinessError, AuthenticationError, etc.)
3. Result types (Result, Ok, Err)
4. Domain primitives (UUID, Money, Entity, ValueObject)

Without adapters, each team would reimplement framework-specific plumbing to use these core types. This adapter eliminates that duplication by providing Nitro-specific bindings.

Features

• Route handler support - Drop-in Nitro route error handling
• Standardized JSON responses - All responses follow the ApiSuccess / ApiError envelope
• Zero-configuration error handling - Wraps route handlers automatically
• Full TypeScript support - Comprehensive type definitions included
• Production-ready - Proper error handling, stack traces, cause chains
• Framework isolation - Core has no Nitro dependencies

Installation

npm install @syncafricabs/kernspark-nitro @syncafricabs/kernspark-core nitro

Or with your preferred package manager:

yarn add @syncafricabs/kernspark-nitro @syncafricabs/kernspark-core nitro

pnpm add @syncafricabs/kernspark-nitro @syncafricabs/kernspark-core nitro

Quick Start

// routes/users/[id].ts
import { withNitroErrorHandling, NitroResponseAdapter } from '@syncafricabs/kernspark-nitro';
import { NotFoundError, ValidationError } from '@syncafricabs/kernspark-core';

export default withNitroErrorHandling(async (event) => {
  const id = event.context.params?.id;
  const user = findUser(id);

  if (!user) {
    throw new NotFoundError('User not found');
  }

  return NitroResponseAdapter.ok(event, user, 'User retrieved successfully');
});

// routes/users.ts
export default withNitroErrorHandling(async (event) => {
  if (event.method === 'POST') {
    const body = await readBody(event);

    if (!body.name || !body.email) {
      throw new ValidationError('MISSING_FIELDS', 'Name and email are required');
    }

    const user = createUser(body);
    return NitroResponseAdapter.created(event, user, 'User created successfully');
  }

  const users = await getUsers();
  return NitroResponseAdapter.ok(event, users, 'Users retrieved successfully');
});

Comprehensive Usage

Route Handlers

GET with Error Handling

// routes/users/[id].ts
import { withNitroErrorHandling, NitroResponseAdapter } from '@syncafricabs/kernspark-nitro';
import { NotFoundError } from '@syncafricabs/kernspark-core';

export default withNitroErrorHandling(async (event) => {
  const id = event.context.params?.id;
  const user = findUser(id);

  if (!user) {
    throw new NotFoundError(`User with id ${id} not found`);
  }

  return NitroResponseAdapter.ok(event, user, 'User retrieved successfully');
});

POST with Validation

// routes/users.ts
import { withNitroErrorHandling, NitroResponseAdapter } from '@syncafricabs/kernspark-nitro';
import { ValidationError, ConflictError, BusinessError } from '@syncafricabs/kernspark-core';

export default withNitroErrorHandling(async (event) => {
  const body = await readBody(event);

  if (!body.name || !body.email) {
    throw new ValidationError('MISSING_FIELDS', 'Name and email are required');
  }

  if (!isValidEmail(body.email)) {
    throw new ValidationError('INVALID_EMAIL', 'Email format is invalid');
  }

  const existingUser = findUserByEmail(body.email);
  if (existingUser) {
    throw new ConflictError('User with this email already exists');
  }

  if (body.balance < 0) {
    throw new BusinessError('INVALID_BALANCE', 400, 'Balance cannot be negative');
  }

  const user = createUser(body);
  return NitroResponseAdapter.created(event, user, 'User created successfully');
});

Error Handling

Custom Error Handler Configuration

import { createNitroErrorHandler, NitroErrorHandlerOptions } from '@syncafricabs/kernspark-nitro';

const options: NitroErrorHandlerOptions = {
  logErrors: true,
  logStack: true,
  includeCause: true,
  includeStack: process.env.NODE_ENV === 'development',
  defaultStatusCode: 500,
  logger: (error, context) => {
    console.error({
      method: context.method,
      path: context.path,
      params: context.params,
      error: error.message,
      stack: error.stack,
    });
  },
};

export default withNitroErrorHandling(handler, options);

Response Adapter

Success Responses

import { NitroResponseAdapter } from '@syncafricabs/kernspark-nitro';

// 200 OK with data
NitroResponseAdapter.ok(event, user, 'User retrieved');

// 201 Created with data
NitroResponseAdapter.created(event, user, 'User created');

// 204 No Content
NitroResponseAdapter.noContent(event);

Error Responses

import { NitroResponseAdapter } from '@syncafricabs/kernspark-nitro';

NitroResponseAdapter.badRequest(event, 'MISSING_FIELDS', 'Email and password are required');
NitroResponseAdapter.unauthorized(event, 'INVALID_CREDENTIALS', 'Invalid email or password');
NitroResponseAdapter.forbidden(event, 'PERMISSION_DENIED', 'You do not have permission');
NitroResponseAdapter.notFound(event, 'NOT_FOUND', 'User not found');
NitroResponseAdapter.conflict(event, 'CONFLICT', 'Resource already exists');
NitroResponseAdapter.unprocessableEntity(event, 'INVALID_DATA', 'Invalid request data');
NitroResponseAdapter.tooManyRequests(event, 'RATE_LIMIT_EXCEEDED', 'Too many requests');
NitroResponseAdapter.internalServerError(event, 'INTERNAL_ERROR', 'An unexpected error occurred');
NitroResponseAdapter.badGateway(event, 'BAD_GATEWAY', 'Upstream service error');
NitroResponseAdapter.serviceUnavailable(event, 'SERVICE_UNAVAILABLE', 'Service temporarily unavailable');
NitroResponseAdapter.gatewayTimeout(event, 'GATEWAY_TIMEOUT', 'Upstream service timeout');

With Error Handling Wrapper

The withNitroErrorHandling function wraps route handlers and automatically catches ApplicationError instances:

import { withNitroErrorHandling, NitroResponseAdapter } from '@syncafricabs/kernspark-nitro';
import { NotFoundError, ValidationError } from '@syncafricabs/kernspark-core';

export default withNitroErrorHandling(async (event) => {
  const id = event.context.params?.id;
  const user = findUser(id);

  if (!user) {
    throw new NotFoundError('User not found');
  }

  return NitroResponseAdapter.ok(event, user);
});

API Reference

nitroErrorHandler

Nitro error handling handler. Catches all errors and maps them to standardized JSON responses.

function nitroErrorHandler(error: Error, event: any): void;

createNitroErrorHandler(options?: NitroErrorHandlerOptions)

Creates a customized error handler.

| Option | Type | Default | Description | |--------|------|---------|-------------| | logErrors | boolean | true | Enable/disable error logging | | logStack | boolean | false | Include stack traces in logs | | includeCause | boolean | true | Include error cause in response | | includeStack | boolean | false | Include stack traces in response (dev only) | | defaultStatusCode | number | 500 | Default status for unknown errors | | logger | function | console.error | Custom logger function |

NitroResponseAdapter

Static utility class for sending responses.

| Method | HTTP Status | Description | |--------|-------------|-------------| | ok(event, data?, message?) | 200 | Send success response with data | | created(event, data?, message?) | 201 | Send created response with data | | noContent(event, message?) | 204 | Send no content response | | sendSuccess(event, apiSuccess) | varies | Send raw ApiSuccess | | sendError(event, apiError) | varies | Send raw ApiError | | badRequest(event, errorCode, message) | 400 | Send bad request error | | unauthorized(event, errorCode, message) | 401 | Send unauthorized error | | forbidden(event, errorCode, message) | 403 | Send forbidden error | | notFound(event, errorCode, message) | 404 | Send not found error | | conflict(event, errorCode, message) | 409 | Send conflict error | | unprocessableEntity(event, errorCode, message) | 422 | Send unprocessable entity error | | tooManyRequests(event, errorCode, message) | 429 | Send too many requests error | | internalServerError(event, errorCode, message) | 500 | Send internal server error | | badGateway(event, errorCode, message) | 502 | Send bad gateway error | | serviceUnavailable(event, errorCode, message) | 503 | Send service unavailable error | | gatewayTimeout(event, errorCode, message) | 504 | Send gateway timeout error |

withNitroErrorHandling(handler, options?)

Wraps a Nitro route handler with error handling.

function withNitroErrorHandling<T extends NitroRouteHandler>(
  handler: T,
  options?: NitroErrorHandlerOptions
): NitroRouteHandler;

Error Handling Reference

The error handler maps the following ApplicationError subclasses:

| Error Class | HTTP Status | Error Code | |-------------|-------------|------------| | ValidationError | 400 | Custom (e.g., INVALID, MISSING_FIELDS) | | MissingFieldsError | 400 | MISSING_FIELDS | | BusinessError | Varies | Custom | | ConflictError | 409 | CONFLICT | | InsufficientFundsError | 400 | INSUFFICIENT_FUNDS | | QuotaExceededError | 429 | QUOTA_EXCEEDED | | NotFoundError | 404 | NOT_FOUND | | ExpiredError | 410 | EXPIRED | | TooManyRequestsError | 429 | TOO_MANY_REQUESTS | | PaymentRequiredError | 402 | PAYMENT_REQUIRED | | LockedError | 423 | LOCKED | | AccountSuspendedError | 403 | ACCOUNT_SUSPENDED | | FeatureNotAvailableError | 501 | FEATURE_NOT_AVAILABLE | | DataIntegrityError | 422 | DATA_INTEGRITY_ERROR | | AuthenticationError | 401 | Custom (e.g., INVALID_TOKEN) | | InvalidTokenError | 401 | INVALID_TOKEN | | TokenExpiredError | 401 | TOKEN_EXPIRED | | SessionExpiredError | 401 | SESSION_EXPIRED | | AuthorizationError | Varies | Custom | | PermissionDeniedError | 403 | PERMISSION_DENIED | | NotAllowedError | 403 | NOT_ALLOWED | | InfrastructureError | Varies | Custom | | ExternalServiceError | 502 | EXTERNAL_SERVICE_ERROR | | BadGatewayError | 502 | BAD_GATEWAY | | GatewayTimeoutError | 504 | GATEWAY_TIMEOUT | | ServiceUnavailableError | 503 | SERVICE_UNAVAILABLE | | RequestFailedError | 500 | REQUEST_FAILED | | NotImplementedError | 501 | NOT_IMPLEMENTED | | MaintenanceModeError | 503 | MAINTENANCE_MODE |

Unknown ApplicationError instances use their embedded statusCode. Non-ApplicationError errors return HTTP 500 with INTERNAL_SERVER_ERROR code.

TypeScript Support

Full TypeScript support with strict mode enabled. The adapter extends Nitro types:

// Nitro event type augmentation
interface NitroRouteContext {
  method: string;
  path: string;
  context: any;
}

Strict Mode

This package is compiled with strict: true. Enable strict mode in your project for full type safety:

{
  "compilerOptions": {
    "strict": true,
    "noImplicitAny": true,
    "strictNullChecks": true
  }
}

Compatibility Matrix

| Package Version | Node.js | Nitro | @syncafricabs/kernspark-core | |----------------|---------|-------|----------------------------------| | 1.0.0 | >=18.0.0 | ^2.6.0 | ^1.0.0 |

| Feature | Nitro 2.6+ | |---------|-------------| | Route handlers | Supported | | Error handling | Supported | | Response utilities | Supported | | TypeScript 5.0+ | Supported |

Contributing

1. Fork the repository
2. Create your feature branch: git checkout -b feature/my-feature
3. Commit your changes: git commit -am 'Add my feature'
4. Push to the branch: git push origin feature/my-feature
5. Submit a pull request

Development Setup

# Clone the repository
git clone https://github.com/iamprovy-dev/kernspark-js.git
cd kernspark/packages/kernspark-nitro

# Install dependencies
npm install

# Build
npm run build

# Run lint
npm run lint

# Run tests
npm test

Code Standards

• Use TypeScript with strict mode
• Follow the existing code style (2-space indentation, semicolons)
• Ensure all tests pass before submitting PR

License

Apache-2.0

Author

Providence Chikukwa

• Email: [email protected]
• GitHub: https://github.com/iamprovy-dev
• LinkedIn: https://www.linkedin.com/in/provychikukwa
• Organization: SyncAfrica Business Solutions