📬 emval

emval is a blazingly fast email validator written in Rust with Python bindings, offering performance improvements of 100-1000x over traditional validators.

Features

• Drop-in replacement for popular email validators like python-email-validator, verify-email, and pyIsEmail.
• 100-1000x faster than python-email-validator.
• Validates email address syntax according to RFC 5322 and RFC 6531.
• Checks domain deliverability (coming soon).
• Supports internationalized domain names (IDN) and local parts.
• Provides user-friendly syntax errors.
• Normalizes addresses.
• Rejects invalid and unsafe Unicode characters.

Getting Started

Install emval from PyPI:

pip install emval

or use emval in a Rust project:

cargo add emval

Usage

Quick Start

To validate an email address in Python:

from emval import validate_email, EmailValidator

email = "example@domain.com"

try:
    # Check if the email is valid.
    val_email = validate_email(email)
    # Utilize the normalized form for storage.
    normalized_email = val_email.normalized
except Exception as e:
    # Example: "Invalid Local Part: Quoting the local part before the '@' sign is not permitted in this context."
    print(str(e))

The same code in Rust:

use emval::{validate_email, ValidationError};

fn main() -> Result<(), ValidationError> {
    let email = "example@domain.com";
    let val_email = validate_email(email)?;
    let normalized_email = val_email.normalized;
    Ok(())
}

Configurations

Customize email validation behavior using the EmailValidator class:

from emval import EmailValidator

emval = EmailValidator(
    allow_smtputf8=False,
    allow_empty_local=True,
    allow_quoted_local=True,
    allow_domain_literal=True,
    deliverable_address=False,
)

email = "user@[192.168.1.1]"

try:
    validated_email = emval.validate_email(email)
    print(validated_email)
except Exception as e:
    print(str(e))

The same code in Rust:

use emval::{EmailValidator, ValidationError};

fn main() -> Result<(), ValidationError> {
    let emval = EmailValidator {
        allow_smtputf8: false,
        allow_empty_local: true,
        allow_quoted_local: true,
        allow_domain_literal: true,
        deliverable_address: false,
    };

    let email = "example@domain.com";
    let validated_email = emval.validate_email(email)?;
    Ok(())
}

Options

• allow_smtputf8: Allows internationalized email addresses.
• allow_empty_local: Allows an empty local part (e.g., @domain.com).
• allow_quoted_local: Allows quoted local parts (e.g., "user name"@domain.com).
• allow_domain_literal: Allows domain literals (e.g., [192.168.0.1]).
• deliverable_address: Checks if the email address is deliverable by verifying the domain's MX records.

Technical Details

Email Address Syntax

emval adheres to the syntax rules defined in RFC 5322 and RFC 6531. It supports both ASCII and internationalized characters.

Internationalized Email Addresses

Domain Names

emval converts non-ASCII domain names into their ASCII "Punycode" form according to IDNA 2008. This ensures compatibility with systems that do not support Unicode.

Local Parts

emval allows international characters in the local part of email addresses, following RFC 6531. It offers options to handle environments without SMTPUTF8 support.

Unsafe Unicode Characters

emval rejects unsafe Unicode characters to enhance security, preventing display and interpretation issues.

Normalization

emval normalizes email addresses to ensure consistency:

• Lowercasing domains: Domain names are standardized to lowercase.
• Unicode NFC normalization: Characters are transformed into their precomposed forms.
• Removing unnecessary characters: Quotes and backslashes in the local part are removed.

Acknowledgements

This project draws inspiration from python-email-validator. While python-email-validator is more comprehensive, emval aims to provide a faster solution.

Getting Help

For questions and issues, please open an issue in the GitHub issue tracker.

License

emval is licensed under the MIT License. See the LICENSE file for more details.