Front Line

A declarative, zero-copy HTTP router for Rust.

The front-line crate offers utilities to route HTTP requests based on their method and path. With declarative macro-driven approach, it's suitable for both complex and straightforward use cases.

Table of Contents

• Features
• Basic Usage
• Testing

Features

• Declarative: With the help of proc-macro attributes, you can easily define routes as enums.
• Zero-copy capture: Dynamic segments from paths, such as /users/{id}, can be captured without unnecessary data copying, ensuring efficient memory usage.
• Dispatch free: The crate focuses purely on route resolution based on the path, leaving dispatch methods up to the user's discretion.

Basic Usage

use front_line::{FrontLine, HttpVersion, RouterResult, Router};

#[derive(FrontLine)]
enum MarketingRoutes {
    #[get("/")]
    RenderIndex,
    #[get("/sign-up")]
    RenderSignUp,
    #[post("/sign-up")]
    ProcessSignUp,
    #[get("/log-in")]
    RenderLogIn,
    #[post("/log-in")]
    ProcessLogIn,
    #[get("/portal")]
    RenderPortal,
}

#[derive(FrontLine)]
#[prefix("/api")]
enum ApiRoutes<'a> {
    #[get("/users")]
    GetAllUsers,
    #[post("/users")]
    CreateUser,
    #[get("/users/{id}")]
    GetUser { id: u32 },
    #[get("/users/{id}/roles/{role}")]
    GetUserRole { id: u32, role: &'a str },
    #[put("/users/{id}/roles/{role}")]
    UpdateUserRole { id: u32, role: &'a str },
}

#[derive(FrontLine)]
enum AllRoutes<'a> {
    #[flatten]
    Marketing(MarketingRoutes),
    #[flatten]
    Api(ApiRoutes<'a>),
}

// Construct an example http request, typically read from a socket.
let request = b"GET /api/users/42?a=b HTTP/1.1\r\n\r\nContent-Length: 12\r\n\r\nHello World!";

// Parse and resolve the route
let route = AllRoutes::resolve(request);

// For demonstration purposes, assert the resolved route matches expectations
assert!(matches!(route, Ok(RouterResult {
  route: Some(AllRoutes::Api(ApiRoutes::GetUser { id: 42 })),
  query: "a=b",
  version: HttpVersion::OneOne,
  head_and_body: b"Content-Length: 12\r\n\r\nHello World!",
})));

Testing

Tests should run fine with the standard cargo test.

However, for consistency, we recommend using the dockerized test environment. To use the dockerized test environment the only requirements are make and docker (you don't even need rust installed locally). Simply run the following command.

make test