error

The error.rs file contains a Rust module that defines an error handling mechanism for a Rocket web framework application.

The module defines a custom error type, Error, which is an enumeration that represents the possible error states of the application. The #[derive(Debug, Error)] attribute is used to automatically implement the Debug trait and the Error trait for the Error type. The thiserror crate is used to provide a convenient way to define error types in Rust.

The possible error states are defined using the #[error("error message")] attribute on each variant of the Error enum. For example, StudyNotFound variant indicates that a study was not found.

The impl<'r> Responder<'r, 'static> for Error implementation defines how the errors should be responded to by the web server. This allows for easy handling of errors and returning appropriate responses to clients.

The respond_to method on the Responder trait is implemented to match on the various Error variants and return the appropriate HTTP response code and message.

• For example, the StudyNotFound variant returns a 404 Not Found response with the error message as the body.