In a recent project, I had to implement complex validation logic for an e-commerce checkout process. The challenge was ensuring that the user’s input met all necessary conditions before proceeding with payment.
I approached this by breaking down the problem into smaller tasks and using a combination of client-side and server-side validations. Client-side validations were used for immediate feedback on basic requirements like format and completeness. This included checks such as verifying if fields were not empty or if email addresses followed the correct pattern.
Server-side validations were implemented to handle more complex scenarios. For instance, checking if a product was in stock or if a discount code was valid and applicable to the items in the cart. These validations required interaction with our database and business logic.
To maintain readability and separation of concerns, I encapsulated each validation rule within its own function. This made it easier to test individual rules and reuse them across different parts of the application.
