#salvo #web #framework #server

salvo

Salvo is a powerful and simplest web server framework in Rust world

31 releases (8 breaking)

Uses new Rust 2021

0.16.8 Jan 12, 2022
0.16.7 Dec 26, 2021
0.16.5 Nov 19, 2021
0.11.6 Jun 30, 2021
0.1.6 Feb 23, 2020

#4 in HTTP server

Download history 74/week @ 2021-09-30 16/week @ 2021-10-07 116/week @ 2021-10-14 107/week @ 2021-10-21 94/week @ 2021-10-28 104/week @ 2021-11-04 123/week @ 2021-11-11 191/week @ 2021-11-18 39/week @ 2021-11-25 142/week @ 2021-12-02 2452/week @ 2021-12-09 4384/week @ 2021-12-16 4992/week @ 2021-12-23 4416/week @ 2021-12-30 5085/week @ 2022-01-06 4316/week @ 2022-01-13

19,395 downloads per month
Used in http-api-problem

MIT/Apache

400KB
6.5K SLoC

Savlo

build status build status build status
crates.io Documentation unsafe forbidden Rust Version
codecov Website License

Salvo is a powerful and simplest web server framework in Rust world.

🎯 Features

  • Base on hyper, tokio and async supported;
  • Websocket supported;
  • Middleware is handler and support executed before or after handler;
  • Easy to use routing system, routers can be nested, and you can add middlewares on any routers;
  • Multipart form supported, handle files upload is very simple;
  • Serve a static virtual directory from many physical directories;

⚡️ Quick start

You can view samples here, or view offical website.

Create a new rust project:

cargo new hello_salvo --bin

Add this to Cargo.toml

[dependencies]
salvo = { version = "0.16", features = ["full"] }
tokio = { version = "1", features = ["full"] }

Create a simple function handler in the main.rs file, we call it hello_world, this function just render plain text "Hello World".

use salvo::prelude::*;

#[fn_handler]
async fn hello_world(res: &mut Response) {
    res.render_plain_text("Hello World");
}

In the main function, we need to create a root Router first, and then create a server and call it's bind function:

use salvo::prelude::*;

#[fn_handler]
async fn hello_world() -> &'static str {
    "Hello World"
}
#[tokio::main]
async fn main() {
    let router = Router::new().get(hello_world);
    Server::new(TcpListener::bind("127.0.0.1:7878")).serve(router).await;
}

Middleware

There is no difference between Handler and Middleware, Middleware is just Handler. So you can write middlewares without to know concpets like associated type, generic type. You can write middleware if you can write function!!!*

Tree-like routing system

Normally we write routing like this:

Router::with_path("articles").get(list_articles).post(create_article);
Router::with_path("articles/<id>")
    .get(show_article)
    .patch(edit_article)
    .delete(delete_article);

Often viewing articles and article lists does not require user login, but creating, editing, deleting articles, etc. require user login authentication permissions. The tree-like routing system in Salvo can meet this demand. We can write routers without user login together:

Router::with_path("articles")
    .get(list_articles)
    .push(Router::with_path("<id>").get(show_article));

Then write the routers that require the user to login together, and use the corresponding middleware to verify whether the user is logged in:

Router::with_path("articles")
    .hoop(auth_check)
    .post(list_articles)
    .push(Router::with_path("<id>").patch(edit_article).delete(delete_article));

Although these two routes have the same path("articles"), they can still be added to the same parent route at the same time, so the final route looks like this:

Router::new()
    .push(
        Router::with_path("articles")
            .get(list_articles)
            .push(Router::with_path("<id>").get(show_article)),
    )
    .push(
        Router::with_path("articles")
            .hoop(auth_check)
            .post(list_articles)
            .push(Router::with_path("<id>").patch(edit_article).delete(delete_article)),
    );

<id> matches a fragment in the path, under normal circumstances, the article id is just a number, which we can use regular expressions to restrict id matching rules, r"<id:/\d+/>".

You can also use <*> or <**> to match all remaining path fragments. In order to make the code more readable, you can also add appropriate name to make the path semantics more clear, for example: <**file_path>.

File upload

We can get file async by the function get_file in Request:

#[fn_handler]
async fn upload(req: &mut Request, res: &mut Response) {
    let file = req.get_file("file").await;
    if let Some(file) = file {
        let dest = format!("temp/{}", file.filename().unwrap_or_else(|| "file".into()));
        if let Err(e) = tokio::fs::copy(&file.path, Path::new(&dest)).await {
            res.set_status_code(StatusCode::INTERNAL_SERVER_ERROR);
        } else {
            res.render_plain_text("Ok");
        }
    } else {
        res.set_status_code(StatusCode::BAD_REQUEST);
    }
}

More Examples

Your can find more examples in examples folder. You can run these examples with the following command:

cargo run --example basic_auth

You can use any example name you want to run instead of basic_auth here.

There is a real and open source project use Salvo: https://github.com/driftluo/myblog.

🚀 Performance

Benchmark testing result can be found from here:

https://web-frameworks-benchmark.netlify.app/result?l=rust

https://www.techempower.com/benchmarks/#section=test&runid=1922b097-2d7f-413c-be21-9571c8302734&hw=ph&test=query&l=zik0zj-e6&a=2

🩸 Contributing

Contributions are absolutely, positively welcome and encouraged! Contributions come in many forms. You could:

  • Submit a feature request or bug report as an issue;
  • Comment on issues that require feedback;
  • Contribute code via pull requests;
  • Publish Salvo-related technical articles on blogs or technical platforms。

All pull requests are code reviewed and tested by the CI. Note that unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in Salvo by you shall be dual licensed under the MIT License, without any additional terms or conditions.

☕ Supporters

Salvo is an open source project. If you want to support Salvo, you can ☕ buy a coffee here.

⚠️ License

Salvo is licensed under either of

Dependencies

~25MB
~592K SLoC