Angular Frontend Code Review Checklist: Ensuring Quality in Your Angular Apps

Angular has established itself as a robust framework for building scalable web applications. To maintain high standards in your Angular projects, a thorough code review process is essential.

Here’s a comprehensive checklist to guide you through reviewing Angular frontend code:

1. Component Architecture
   • Are components following the single responsibility principle?
   • Is there a clear separation between smart (container) and presentational components?
   • Are components kept reasonably small and focused?
2. Template Syntax
   • Is the template syntax clean and easy to read?
   • Are structural directives (*ngIf, *ngFor) used appropriately?
   • Is there any logic in templates that should be moved to the component class?
3. Data Binding
   • Is property binding [] used correctly for input properties?
   • Is event binding () used properly for outputs?
   • Are two-way bindings [(ngModel)] used sparingly and appropriately?
4. Dependency Injection
   • Are services properly injected and used?
   • Is the dependency injection hierarchy logical?
   • Are providers declared at the appropriate level (component, module, or root)?
5. Modules
   • Is the application properly modularized?
   • Are feature modules used to organize related functionality?
   • Is lazy loading implemented for larger modules to improve initial load time?
6. Routing
   • Is the routing configuration clean and well-organized?
   • Are route guards (CanActivate, CanDeactivate) used where necessary?
   • Is route data and resolvers used effectively?
7. Forms
   • Is there a consistent approach to form handling (Template-driven vs Reactive)?
   • Are form validations implemented and working correctly?
   • Is error handling for forms user-friendly?
8. State Management
   • For complex apps, is a state management solution (NgRx, NGXS, Akita) used consistently?
   • Are actions, reducers, and effects (if applicable) well-defined and following best practices?
9. RxJS Usage
   • Are observables used effectively and unsubscribed properly to avoid memory leaks?
   • Is the async pipe utilized in templates where possible?
   • Are RxJS operators used efficiently for data transformation and event handling?
10. Performance Optimization
    • Is change detection strategy set to OnPush where appropriate?
    • Are heavy computations memoized or moved to pure pipes?
    • Is trackBy function used with *ngFor for large lists?
11. Error Handling
    • Are errors gracefully handled and logged?
    • Is there a global error handling strategy?
    • Are HTTP errors handled gracefully?
    • Are user-facing error messages clear and helpful?
12. Testing
    • Are there unit tests for components, services, and pipes?
    • Are integration tests in place for critical user flows?
    • Is TestBed used correctly in setting up test environments?
13. Styling
    • Is there a consistent approach to styling (CSS, SCSS, CSS-in-JS)?
    • Are styles properly scoped to components?
    • Is the overall styling structure maintainable and following Angular best practices?
14. Internationalization (i18n)
    • Are all user-facing strings properly internationalized?
    • Is the Angular i18n system or a third-party library used consistently?
15. Accessibility (a11y)
    • Are ARIA attributes used where necessary?
    • Is the application navigable via keyboard?
    • Do all interactive elements have proper focus management?
16. Code Style and Formatting
    • Does the code adhere to the Angular style guide?
    • Is the codebase consistently formatted? (Consider using tools like Prettier)
    • Are naming conventions clear and consistent?
17. Documentation
    • Are complex logic or algorithms properly commented?
    • Is there sufficient documentation for custom services and components?
    • Are public APIs of services and components well-documented?
18. Build and Deploy Configuration
    • Is the Angular CLI used effectively for development, testing, and production builds?
    • Are environment-specific configurations properly set up?
19. Security
    • Is user input sanitized to prevent XSS attacks?
    • Are security best practices followed for handling sensitive data?
20. Dependencies
    • Are all dependencies necessary and up-to-date?
    • Is there a strategy for managing and updating dependencies?

By following this checklist, you can ensure that your Angular frontend code is maintainable, performant, and adheres to best practices. Remember, code reviews are an opportunity not just to catch bugs, but also to share knowledge and improve the overall quality of your Angular application.