Periodic hot reloader and notifier for files, KVS, etc. for Rust

This provides a Rust trait definition and service library for hot-reloading your files, KVS, etc. by periodically checking the system.

Reload Trait Definition

To use this library, you need to prepare your own struct implementing reloader::Reload trait, defined as follows:

```rust

[async_trait]

/// Trait defining the responsibility of reloaders to periodically load the target value V from Source. /// Source could be a file, a KVS, whatever if you can implement Reload<V> with Reload<V>::Source. pub trait Reload where V: Eq + PartialEq { type Source; async fn new(src: &Self::Source) -> Result> where Self: Sized; async fn reload(&self) -> Result, ReloaderError>; } ```

This trait defines the source type (file, KVS, etc) and reloaded object type V. The following is an example of periodic-reloading a config-file through a given file path string.

```rust pub struct ConfigReloader { pub config_path: PathBuf, }

[async_trait]

impl Reload for ConfigReloader { type Source = String; async fn new(source: &Self::Source) -> Result> { Ok(Self { config_path: PathBuf::from(source), }) }

async fn reload(&self) -> Result, ReloaderError> { let configstr = std::fs::readtostring(&self.configpath).context("Failed to read config file")?; let config: ServerConfig = configobjectfromstr(configstr);

Ok(Some(config))

} } ```

Usage

```rust use hot_reload::*;

let (reloader, rx) = ReloaderService::new(source, 10, false).await.unwrap(); tokio::spawn(async move { reloaderservice.start().await }); loop { tokio::select! { // Add main logic of the event loop with up-to-date value _ = something.happened() => { // ... } // immediately update if watcher detects the change _ = rx.changed() => { if rx.borrow().isnone() { break; } let value = rx.borrow().clone(); info!("Received value via watcher"); info!("value: {:?}", value.unwrap().clone()); } else => break } } } ```