@aicone/pem

@aicone/pem is a JavaScript library for handling PEM-encoded strings, providing methods to validate and extract various PEM types, such as certificates, public keys, and private keys. This library supports different PEM types, including RSA, DSA, and EC formats, making it ideal for working with secure data in cryptographic and certificate-based applications.

Table of Contents

• Installation
• Features
• Usage
  • Extracting Certificates
  • Extracting Public Keys
  • Extracting Private Keys
• API Reference
• Examples
• License

Installation

To add @aicone/pem to your Deno project, use:

deno add jsr:@aicone/pem

Features

• Supports Multiple PEM Types: Handles RSA PRIVATE KEY, CERTIFICATE, RSA PUBLIC KEY, DSA PRIVATE KEY, and more.
• Error Handling: Throws a TypeError if the PEM string does not match the expected format.
• Regex-based Validation: Validates PEM strings with a regular expression.

Usage

Importing the Library

import { pem, Pem } from 'jsr:@aicone/pem';

Extracting Certificates

Use the certificate() method to extract a certificate PEM string. If the string format is invalid, a TypeError is thrown.

const pemString = '-----BEGIN CERTIFICATE-----\n...base64 data...\n-----END CERTIFICATE-----';
const pemObject = pem(pemString);
try {
  const certificate = pemObject.certificate();
  console.log(certificate);
} catch (error) {
  console.error(error); // Expected PEM format CERTIFICATE
}

Extracting Public Keys

Use the publicKey() method to retrieve a public key PEM string. Optionally, specify "RSA" for RSA public keys.

try {
  const publicKey = pemObject.publicKey("RSA");
  console.log(publicKey);
} catch (error) {
  console.error(error); // Expected PEM format RSA PUBLIC KEY
}

Extracting Private Keys

The privateKey() method retrieves a private key PEM string. Optionally, specify "RSA", "DSA", or "EC" for specific types of private keys.

try {
  const privateKey = pemObject.privateKey("RSA");
  console.log(privateKey);
} catch (error) {
  console.error(error); // Expected PEM format RSA PRIVATE KEY
}

API Reference

pem(string)

Takes a PEM string as input and returns an instance of the Pem class.

• Parameters:
  • string (string): The PEM-encoded string.
• Returns: Pem instance.

Pem Class

The Pem class provides methods to extract and validate PEM strings for various types.

certificate()

Returns the certificate PEM string if it exists in the input; otherwise, throws a TypeError.

• Returns: string | TypeError

publicKey(type)

Retrieves a public key PEM string based on the specified type, defaulting to any public key if no type is provided.

• Parameters:
  • type (string, optional): Specify "RSA" for RSA public keys.
• Returns: string | TypeError

privateKey(type)

Retrieves a private key PEM string based on the specified type, defaulting to any private key if no type is provided.

• Parameters:
  • type (string, optional): Specify "RSA", "DSA", or "EC" for specific private key types.
• Returns: string | TypeError

Examples

Example 1: Validating and Extracting a Certificate

const pemString = '-----BEGIN CERTIFICATE-----\n...base64 data...\n-----END CERTIFICATE-----';
const pemObject = pem(pemString);
try {
  console.log(pemObject.certificate());
} catch (error) {
  console.error(error.message);
}

Example 2: Extracting an RSA Public Key

const pemObject = pem('-----BEGIN RSA PUBLIC KEY-----\n...base64 data...\n-----END RSA PUBLIC KEY-----');
try {
  console.log(pemObject.publicKey("RSA"));
} catch (error) {
  console.error(error.message);
}

Example 3: Extracting an EC Private Key

const pemObject = pem('-----BEGIN EC PRIVATE KEY-----\n...base64 data...\n-----END EC PRIVATE KEY-----');
try {
  console.log(pemObject.privateKey("EC"));
} catch (error) {
  console.error(error.message);
}

Contributing

Contributions to improve the library are welcome. Please open an issue or pull request on the GitHub repository.

Donation

• https://paypal.me/aiconeid

License

This project is licensed under the MIT License.