Debugging and testing are essential components of any software development process. When it comes to swift app development, understanding how to effectively debug and test your code can be the difference between success and failure. In this article, we'll delve into the world of debugging and testing, providing you with a comprehensive guide on how to navigate the process like a pro.

Project Structure Overview

Before diving into the debugging process, it's essential to understand the project structure. A well-organized codebase is crucial for effective debugging. The AsyncAPI CLI, for instance, has a structured directory layout that includes:

  • apps/: Holds the API server and CLI applications
  • domains/: Contains domain models and services
  • errors/: Custom error classes
  • interfaces/: TypeScript interfaces
  • utils/: Utility functions

Understanding this structure will help you navigate the codebase more efficiently.

Setting Up Your Environment

To begin debugging, you'll need to set up your environment. This involves installing dependencies, building the project, and setting environment variables for development mode.

  1. Install Dependencies: Run npm install to install all required dependencies.
  2. Build the Project: Run npm run build to compile the codebase.
  3. Set Environment Variables: Create a .env file or export the following variables:
  • NODE_ENV=development: Enables development mode with verbose logging.
  • TEST=1: Disables analytics during testing.
  • CUSTOM_CONTEXT_FILENAME="test.asyncapi-cli": Sets the custom context file for testing.

Debugging CLI Commands

Debugging CLI commands is a crucial step in ensuring your code runs smoothly. Here are four methods to help you debug:

Method 1: Using bin/run

Run any command with debugging using the bin/run script:

`

./bin/run validate ./path/to/asyncapi.yml

`

To enable verbose output, add the following flag:

`

DEBUG=* ./bin/run validate ./path/to/asyncapi.yml

`

Method 2: Using Node.js Inspector

Start with Node inspector and then open Chrome DevTools at chrome://inspect:

`

node --inspect-brk ./bin/run validate ./path/to/asyncapi.yml

`

Method 3: VS Code Debugging

Create a .vscode/launch.json file:

`json

{

"version": "0.2.0",

"configurations": [

{

"type": "node",

"request": "launch",

"name": "Debug CLI Command",

"program": "${workspaceFolder}/bin/run",

"args": ["validate", "./test/fixtures/specification.yml"],

"env": {

"NODE_ENV": "development",

"TEST": "1"

},

"sourceMaps": true,

"outFiles": ["${workspaceFolder}/lib/**/*.js"]

}

]

}

`

Method 4: Adding Console Logs

Add logs in command files for quick debugging:

`ts

// In src/apps/cli/commands/validate.ts

async run() {

const { args, flags } = await this.parse(Validate);

// Debug: Log parsed arguments

console.log('DEBUG - Args:', JSON.stringify(args, null, 2));

console.log('DEBUG - Flags:', JSON.stringify(flags, null, 2));

}

`

Debugging the API Server

Debugging the API server involves starting it in development mode and testing endpoints.

Starting the API in Development Mode

Start the API with hot-reload:

`

npm run api:dev

`

Or manually with debugging:

`bash

NODE_ENV=development DEBUG=* node ./lib/apps/api/server.js

`

Testing API Endpoints

Test endpoints using tools like curl:

`bash

# Validate endpoint

curl -X POST http://localhost:3000/v1/validate \

-H "Content-Type: application/json" \

-d '{"asyncapi": "asyncapi: 3.1.0\ninfo:\n title: Test\n version: 1.0.0\nchannels: {}"}'

# Parse endpoint

curl -X POST http://localhost:3000/v1/parse \

-H "Content-Type: application/json" \

-d '{"asyncapi": "..."}'

`

Debugging API Controllers

Add middleware logging to debug API controllers:

`ts

// In src/apps/api/middlewares/logger.middleware.ts

// Logs are automatically enabled in development mode

`

Debugging Services

Debug services like ValidationService, ConversionService, and GeneratorService by testing them directly.

ValidationService

Test the service using the following code:

`ts

import { ValidationService } from '@services/validation.service';

import { load } from '@models/SpecificationFile';

async function debugValidation() {

const service = new ValidationService();

const specFile = await load('./path/to/spec.yml');

const result = await service.validateDocument(specFile, {

'fail-severity': 'error',

'log-diagnostics': true,

});

console.log('Validation Result:', JSON.stringify(result, null, 2));

}

`

Writing Tests

Writing tests is an essential part of the debugging process. Here's a brief overview:

Test File Naming Convention

  • Unit tests: test/unit//.test.ts
  • Integration tests: test/integration/.test.ts

Unit Test Structure

`ts

// test/unit/services/my-service.test.ts

import { expect } from 'chai';

import { MyService } from '../../../src/domains/services/my.service';

describe('MyS', () => {

it('should do something', async () => {

// Test implementation

});

});

`

By following these guidelines, you'll be well on your way to mastering the art of debugging and testing in swift app development. Remember to stay organized, use the right tools, and test thoroughly to ensure your code runs smoothly. Happy coding!