Data Validation

Abstract

As you know from the previous chapters, users can make requests using URLs and send data to the application by submitting a form in a view that is then handled by a controller. However, an important question that hasn’t been addressed yet is how to ensure that the data submitted by users is valid. One of the most important tasks when developing software is to include validation logic that ensures that the data received from users is valid, so that the application can work with it. This very important task is also quite challenging for developers because they not only must ensure the data is analyzed for validity but also provide timely feedback to the users so that they can fix any invalid data and resubmit it.