Derive Macro domain_derive::ValueSetup

#[derive(ValueSetup)]

The ValueSetup derive macro can be used to setup as much boilerplate as possible for your choosen value object. It checks some preconditions:

1. You are applying this to a struct.
2. Your struct has a single field called value of any type that is clonable.

Once you've used this macro, you will still need to implement the ValueObject trait, but you will not have to implement TryFrom (or create the validation error for TryFrom, this is handled by the macro), or implement PartialEq or Clone.

In case you need to use the validation error elsewhere, the created validation error will be the name of your struct with ValidationError appended. For example, if you have an Email struct, then the generated validation error will be called EmailValidationError.

#[macro_use]
extern crate domain_derive;

use domain_patterns::ValueObject;
use regex::Regex;

#[derive(ValueSetup)]
pub struct Email {
    pub value: String,
}

impl ValueObject<String> for Email {
    // This error would be the root error for the crate, using failure most likely.
    type ValueError = Error;

    fn validate(value: &String) -> Result<(), Self::ValueError> {
        let email_rx = Regex::new(
            r"^(?i)[a-z0-9.!#$%&'*+/=?^_`{|}~-]+@[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?(?:.[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?)*$"
        ).unwrap();

        if !email_rx.is_match(value) {
            return Err(EmailValidationError)
        }

        Ok(())
    }

    fn value(&self) -> &String {
        return &self.value;
    }
}