rcask

rcask is a bitcask inspired, rust-based in-memory key-value store built on the core concepts of log-structured storage engines.

What does it have?

• In-Memory Index: Key value lookups are supported through HashMap that stores the exact disk offset for each key.
• Log-Structured Persistence: Data is appended to a file in a sequential "log" fashion.
• Compaction: Automatically compacts log files after a configurable number of writes to keep disk usage under control.
• Data Integrity: Keys are read and validated during retrieval to help detect potential data corruption.
• Storage APIs set and get operations for storing and retrieving string-based key-value pairs.
• Crash Recovery: The in-memory index is rebuilt from the log file upon initialization, ensuring data persistence across application restarts.

Examples

use rcask::RCask;
use std::error::Error;

fn main() -> Result<(), Box<dyn Error>> {
    let mut store = RCask::init(
        "./".to_string(), // Directory to store logs
        "log".to_string(), // Pattern for log files
        3)?; // Maximum number of writes before compaction

    // Default store with max_writes as 10000 before compaction
    let mut default_store = RCask::new(
        "./".to_string(), // Directory to store logs
        "default_log".to_string(), // Pattern for log files
    )?;

    store.set("key1", "value1")?;
    store.set("key2", "value2")?;
    store.set("key3", "value3")?;

    println!("Value for key1: {:?}", store.get("key1")?);
    println!("Value for key2: {:?}", store.get("key2")?);
    println!("Value for key3: {:?}", store.get("key3")?);

    store.set("key1", "response: { values: ['A', 'B', 'C'] } ")?;
    println!("Updated value for key1: {:?}", store.get("key1")?);

    return Ok(());
}