Custom Storage Backends

AuthBox uses the UserStore trait to abstract all persistence logic.

This allows integration with any database or storage system.

Supported Backends

You can implement storage using:

• PostgreSQL
• MySQL
• SQLite
• MongoDB
• Redis
• REST APIs
• gRPC services
• In-memory storage

UserStore Trait

#![allow(unused)]
fn main() {
#[async_trait]
pub trait UserStore {
    type Error;
    type User: AuthUser;
    type RegisterDto: RegisterUserInput;

    async fn find_by_id(&self, user_id: &str) -> Option<Self::User>;

    async fn find_by_email(&self, email: &str) -> Option<Self::User>;

    async fn create_user(
        &self,
        input: Self::RegisterDto,
        password_hash: String,
    ) -> Result<Self::User, Self::Error>;

    async fn update_user(
        &self,
        user: Self::User,
    ) -> Result<Self::User, Self::Error>;

    async fn delete_user(
        &self,
        user_id: &str,
    ) -> Result<(), Self::Error>;

    async fn  check_email_verified(
        &self,
        user_id: &str,
    ) -> Result<bool, Self::Error>;
}
}

Implementation Guidelines

When implementing a custom store:

• Ensure thread safety (Arc, connection pools, etc.)
• Avoid blocking operations inside async methods
• Handle errors using your backend’s error type
• Keep queries efficient and indexed
• Ensure email lookup is fast (commonly indexed)

Example Use Cases

• SQL-backed authentication system
• Multi-tenant user storage
• Microservice-based auth backend
• High-performance cache layer (Redis)

Key Benefit

AuthBox does not dictate your database.

You control persistence entirely.