This Node.js command-line application is a fun and educational tool that encodes and decodes strings using the Ethereum blockchain's block hash as the key. Initiated by Singular from the tea community, the idea was born out of a casual conversation where Singular mentioned, "it would be nice if the key to decoding was the Ethereum block number at the sentence generation timestamp.". This application embodies that concept by leveraging the Ethereum block hash, providing a unique twist to string encryption and decryption.

This project is created for fun and educational purposes only. It is not intended for serious cryptographic applications or for securing sensitive data. The use of block hashes as encryption keys in a production environment is not recommended due to security concerns as block hashes are publicly available and can be easily brute-forced.

Before you begin, ensure you have Node.js installed on your system. You can download and install Node.js from https://nodejs.org/.

1. Clone the repository

   Start by cloning this repository to your local machine:

   git clone https://github.com/stevenlei/ethereum-casual-message-coder.git
   cd ethereum-casual-message-coder
   

2. Install dependencies

   Install the necessary Node.js packages:

   npm install
   

3. Set up the .env file

   Copy the .env.example file to .env, and update the ETHEREUM_RPC_URL variable with your Ethereum RPC URL and API key.

   ETHEREUM_RPC_URL=https://your-ethereum-rpc-url/api-key
   

   Replace https://your-ethereum-rpc-url/api-key with your actual Ethereum RPC URL and API key.

To start the application, run:

npm run cli

Follow the prompts to encode or decode strings using the Ethereum block hash.

• Encode Mode: The application asks the user to enter a string and then fetches the latest Ethereum block hash to use as an encryption key. The string is then encrypted, and the resulting encoded string is displayed to the user.

• Decode Mode: The user provides the previously encoded string and the block hash that was used for encoding. The application then attempts to decode the string using the provided block hash. If successful, the original string is displayed; otherwise, an error message is shown.

Feel free to fork this project and make your own changes. Pull requests are welcome!

Special thanks to Singular from the tea community for inspiring this project with their creative idea!

MIT