Credis - A Simple Redis-like Server in C

Credis is a minimalistic Redis-like server implemented in C. It supports basic key-value storage operations such as SET, GET, DEL, EXISTS and PING. The server uses multiplexing with select() to handle multiple client connections concurrently.

Features

• SET key value: Stores a key-value pair in memory.
• GET key: Retrieves the value associated with a key.
• DEL key: Deletes the key-value pair in memory.
• EXISTS key: Checks is the value for a key exists.
• PING: Responds with PONG to check server availability.
• Multiplexing: Handles multiple client connections using select().

How to Build and Run

Prerequisites

• A C compiler (e.g., gcc)
• Basic knowledge of terminal commands

Steps

1. Clone the Repository:

   git clone https://github.com/yourusername/credis.git
   cd credis

2. Compile the Code:

   gcc -o credis main.c domain/multiplexing.c

3. Run the Server:

   ./credis

   By default, the server runs on 127.0.0.1:6379.

   You can specify a custom host and port using the -h and -p options:

   ./credis -h 0.0.0.0 -p 8080

4. Connect to the Server: Use a Redis client (e.g., redis-cli) or telnet to connect to the server:

   redis-cli -h 127.0.0.1 -p 6379

   Or:

   telnet 127.0.0.1 6379

5. Send Commands:

   • Set a key-value pair:

     SET mykey myvalue
     

   • Get the value of a key:

     GET mykey
     

   • Ping the server:

     PING
     

Code Structure

• main.c: Contains the main server logic, including command-line argument parsing, server initialization, and the event loop.
• handle.h: Defines the KeyValue struct and function prototypes for handling client requests.
• multiplexing.c: Implements the handle() function to process client commands and manage the key-value store.

Limitations

• The server supports a maximum of 100 key-value pairs.
• It can handle up to 10 concurrent client connections.
• No persistence: All data is stored in memory and lost when the server stops.
• Basic error handling is implemented, but the server is not production-ready.

Contributing

Contributions are welcome! If you'd like to improve Credis, feel free to open an issue or submit a pull request.

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Enjoy experimenting with Credis! If you have any questions or feedback, feel free to reach out.