Caesar-Cipher

Implementation of the Caesar Cipher encryption algorithm in JavaScript. The Caesar Cipher is a classic substitution cipher technique where each letter in the plaintext is shifted a certain number of places down or up the alphabet.

Features

• TypeScript and JSDoc support
• User-defined alphabets
• Support of array inputs and returns
• Encryption and decryption

Installation

npm install @dunkelhaiser/caesar-cipher

yarn add @dunkelhaiser/caesar-cipher

pnpm add @dunkelhaiser/caesar-cipher

bun add @dunkelhaiser/caesar-cipher

Basic usage

Importing the Library

Using ESM

With named import

import { CaesarCipher } from "@dunkelhaiser/caesar-cipher";

With named imports

import { encrypt, decrypt } from "@dunkelhaiser/caesar-cipher";

With default import

import CaesarCipher from "@dunkelhaiser/caesar-cipher";

Using CommonJS

With default import

const CaesarCipher = require("@dunkelhaiser/caesar-cipher");

With named imports

const { encrypt, decrypt } = require("@dunkelhaiser/caesar-cipher");

Encrypt a string

CaesarCipher.encrypt("Hello My Beautiful World!", 7); // => "Olssv Tf Ilhbapmbs Dvysk!"

Decrypt a string

CaesarCipher.decrypt("Olssv Tf Ilhbapmbs Dvysk!", 7); // => "Hello My Beautiful World!"

Provide an array as a parameter

CaesarCipher.encrypt(["Hello", "My", "Beautiful", "World!"], 7); // => ["Olssv", "Tf", "Ilhbapmbs", "Dvysk!"]

Use own alphabet

If you wish to use a custom alphabet for encryption and decryption, you can provide it as the third parameter:

CaesarCipher.encrypt("Привіт мій прекрасний диво-світ!", 7, "абвгґдеєжзиіїйклмнопрстуфхцчшщьюя"); // => "Цчнзощ уор цчйсчєшфнр їнзх-шзощ!"

Numeric Support

If numbers are provided in the alphabet they also will be shifted, otherwise they stay untouched.

CaesarCipher.encrypt("12345", 5); // => "12345"
CaesarCipher.encrypt("12345", 5, "0123456789"); // => "67890"

API

encrypt(input, shift, alphabet) | decrypt(input, shift, alphabet)

Name	Type	Argument	Default	Description
input	string | string[]	<required>		text to be encrypted
shift	number	<required>		amount to shift each character by
alphabet	string	<optional>	abcdefghijklmnopqrstuvwxyz	alphabet to be used for the cipher

Contributing

Bug Reporting

If you come across a bug or unexpected behavior, please take the time to report it. To file a bug report:

1. Check if the issue has already been reported by searching the issues.
2. If the issue hasn't been reported yet, open a new issue, providing as much detail as possible, including:

• A clear and concise title.
• A detailed description of the issue.
• Steps to reproduce the problem.
• Expected and actual behavior.

Feature Proposals

To propose a new feature:

1. Check the issues to ensure it hasn't been proposed before.
2. Open a new issue, clearly describing the new feature or enhancement you would like to see.
3. Provide any relevant details or use cases that will help understand the use of the proposed feature.

Code Contributions

To contribute code:

1. Fork the repository.
2. Create a new branch for your changes with a specific prefix: git checkout -b feat/your-feature. Accepted prefixes: feat, fix, refactor, docs.
3. Make your changes, following the coding style.
4. Write unit tests for your changes.
5. Update the README or documentation if necessary.
6. Submit a pull request to the dev branch of the original repository.
7. Provide a detailed description in the pull request, explaining the purpose of your changes.

License

Copyright (c) 2024 Kyrylo Tymchyshyn
Licensed under the MIT license.