Rust Form Validation with Serde

Validate form data in Rust using serde Deserialize with custom validation, error collection, and JSON response generation. Includes nested struct validation.

Rust Form Validation Updated: 2026-01-15

Code

snippet

use serde::{Deserialize, Serialize};

#[derive(Deserialize)]
struct LoginForm {
    email: String,
    password: String,
}

#[derive(Serialize)]
struct ValidationError {
    field: String,
    message: String,
}

fn validate(form: &LoginForm) -> Vec<ValidationError> {
    let mut errors = vec![];
    if !form.email.contains('@') {
        errors.push(ValidationError { field: "email".into(), message: "Invalid email".into() });
    }
    if form.password.len() < 8 {
        errors.push(ValidationError { field: "password".into(), message: "Min 8 chars".into() });
    }
    errors
}