Configuring Email Templates

AuthBox separates email delivery from email content.

The EmailTemplateConfig trait is responsible for generating email subjects and bodies for different authentication workflows.

Responsibilities

Email templates are used for:

• Email verification content
• Password reset content

This allows full customization of email wording without changing the email provider logic.

EmailTemplateConfig Trait

To define email templates, implement the following trait:

#![allow(unused)]
fn main() {
pub trait EmailTemplateConfig<U: AuthUser> {
    fn verify_email_subject(&self, user: &U) -> String;

    fn verify_email_body(
        &self,
        user: &U,
        token: &str,
    ) -> String;

    fn reset_password_subject(&self, user: &U) -> String;

    fn reset_password_body(
        &self,
        user: &U,
        token: &str,
    ) -> String;
}
}

Methods

verify_email_subject

Generates the subject line for email verification.

#![allow(unused)]
fn main() {
fn verify_email_subject(&self, user: &U) -> String;
}

verify_email_body

Generates the body content for email verification.

#![allow(unused)]
fn main() {
fn verify_email_body(
    &self,
    user: &U,
    token: &str,
) -> String;
}

reset_password_subject

Generates the subject line for password reset emails.

#![allow(unused)]
fn main() {
fn reset_password_subject(&self, user: &U) -> String;
}

reset_password_body

Generates the body content for password reset emails.

#![allow(unused)]
fn main() {
fn reset_password_body(
    &self,
    user: &U,
    token: &str,
) -> String;
}

Example Implementation

#![allow(unused)]
fn main() {
#[derive(Clone)]
pub struct MockTemplates;

impl EmailTemplateConfig<User> for MockTemplates {
    fn verify_email_subject(&self, _: &User) -> String {
        "Verify Email".to_string()
    }

    fn verify_email_body(
        &self,
        _: &User,
        token: &str,
    ) -> String {
        format!("https:://yourapp/verif_email/token={}", token)
    }

    fn reset_password_subject(
        &self,
        _: &User,
    ) -> String {
        "Reset Password".to_string()
    }

    fn reset_password_body(
        &self,
        _: &User,
        token: &str,
    ) -> String {
        format!("https:://yourapp/reset_password/token={}", token)
    }
}
}

Design Notes

• EmailProvider handles sending emails
• EmailTemplateConfig handles email content
• This separation allows:
  • Different email services
  • Different branding/templates per app
  • Easy localization (i18n support)
  • Clean separation of concerns

Summary

• Implement EmailTemplateConfig to customize email content.
• Used for verification and password reset workflows.
• Works together with EmailProvider but does not depend on it.
• Fully flexible and backend-agnostic design.