salvo-flash 0.89.1

Flash message support for salvo web server framework.
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Salvo is an extremely simple and powerful Rust web backend framework. Only basic Rust knowledge is required to develop backend services.

# salvo-flash


Flash messages middleware for the Salvo web framework. Flash messages are temporary notifications that persist across a single redirect, commonly used to display success, error, or info messages after form submissions.

## Features


- **Multiple storage backends**: Cookie-based or session-based storage
- **Message levels**: Debug, Info, Success, Warning, and Error severity levels
- **Level filtering**: Filter messages by minimum severity level
- **Easy integration**: Simple API for setting and retrieving flash messages
- **Automatic cleanup**: Messages are automatically cleared after being read

## How It Works


1. A handler sets flash messages before redirecting
2. The middleware stores them (in cookies or session)
3. On the next request, the messages are available and then cleared

## Storage Options


| Store | Feature | Description |
|-------|---------|-------------|
| `CookieStore` | `cookie-store` | Stores messages in a cookie |
| `SessionStore` | `session-store` | Stores messages in the session |

## Installation


This is an official crate, so you can enable it in `Cargo.toml`:

```toml
salvo = { version = "*", features = ["flash"] }
```

## Quick Start


```rust
use salvo::prelude::*;
use salvo::flash::{FlashDepotExt, CookieStore};

#[handler]

async fn submit_form(depot: &mut Depot, res: &mut Response) {
    // Set flash message before redirect
    depot.outgoing_flash_mut().success("Form submitted successfully!");
    res.render(Redirect::other("/result"));
}

#[handler]

async fn show_result(depot: &mut Depot, res: &mut Response) {
    if let Some(flash) = depot.incoming_flash() {
        for msg in flash.iter() {
            println!("{}: {}", msg.level, msg.value);
        }
    }
    res.render("Result page");
}

#[tokio::main]

async fn main() {
    let router = Router::new()
        .hoop(CookieStore::new().into_handler())
        .push(Router::with_path("submit").post(submit_form))
        .push(Router::with_path("result").get(show_result));

    let acceptor = TcpListener::new("0.0.0.0:8698").bind().await;
    Server::new(acceptor).serve(router).await;
}
```

## Documentation & Resources


- [API Documentation](https://docs.rs/salvo-flash)
- [Example Projects](https://github.com/salvo-rs/salvo/tree/main/examples)

## ☕ Donate


Salvo is an open source project. If you want to support Salvo, you can ☕ [**buy me a coffee here**](https://ko-fi.com/chrislearn).

## ⚠️ License


Salvo is licensed under either of

- Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or [http://www.apache.org/licenses/LICENSE-2.0](http://www.apache.org/licenses/LICENSE-2.0)).

- MIT license ([LICENSE-MIT](LICENSE-MIT) or [http://opensource.org/licenses/MIT](http://opensource.org/licenses/MIT)).