# Keyed Lock
[](https://crates.io/crates/keyed-lock)
[](https://docs.rs/keyed-lock)
This crate provides a keyed lock, which allows you to lock a resource based on a key. This is useful when you have a collection of resources and you want to lock individual resources by their key.
This crate provides both synchronous and asynchronous implementations.
## Usage
Add this to your `Cargo.toml`:
```toml
[dependencies]
keyed-lock = { version = "0.2", features = ["sync", "async"] }
```
### Synchronous
The `sync` module provides a synchronous `KeyedLock`.
Locks with the same key will block each other, while locks with different keys will not.
```rust
use keyed_lock::sync::KeyedLock;
let lock = KeyedLock::new();
// Lock key "a", this will not block.
let _guard_a = lock.lock("a");
// Lock key "b", this will not block as it's a different key.
let _guard_b = lock.lock("b");
// Try to lock "a" again, this will block until `_guard_a` is dropped.
// let _guard_a2 = lock.lock("a");
```
### Asynchronous
The `async` module provides an asynchronous `KeyedLock`.
Locks with the same key will block each other, while locks with different keys will not.
```rust
use keyed_lock::r#async::KeyedLock;
let lock = KeyedLock::new();
// Lock key "a", this will not block.
let _guard_a = lock.lock("a").await;
// Lock key "b", this will not block as it's a different key.
let _guard_b = lock.lock("b").await;
// Try to lock "a" again, this will block until `_guard_a` is dropped.
// let _guard_a2 = lock.lock("a").await;
```
## Features
- `sync`: Enables the synchronous `KeyedLock`.
- `async`: Enables the asynchronous `KeyedLock`.
By default, both features are enabled.