路由基础 #

路由是Web框架的核心功能，它决定了如何将HTTP请求映射到处理函数。Rocket使用属性宏来定义路由，使代码清晰易读。

什么是路由？ #

路由是将URL路径和HTTP方法映射到处理函数的机制。当用户访问某个URL时，框架会根据路由规则找到对应的处理函数来处理请求。

text

HTTP请求 → 路由匹配 → 处理函数 → 响应

路由定义 #

基本语法 #

Rocket使用属性宏来定义路由：

rust

#[get("/path")]
fn handler() -> &'static str {
    "Response"
}

HTTP方法 #

Rocket支持所有标准HTTP方法：

rust

#[get("/resource")]
fn get_resource() -> &'static str {
    "GET: Read resource"
}

#[post("/resource")]
fn create_resource() -> &'static str {
    "POST: Create resource"
}

#[put("/resource")]
fn update_resource() -> &'static str {
    "PUT: Update resource"
}

#[patch("/resource")]
fn patch_resource() -> &'static str {
    "PATCH: Partial update"
}

#[delete("/resource")]
fn delete_resource() -> &'static str {
    "DELETE: Delete resource"
}

#[head("/resource")]
fn head_resource() -> &'static str {
    "HEAD: Get headers only"
}

#[options("/resource")]
fn options_resource() -> &'static str {
    "OPTIONS: Get allowed methods"
}

方法	用途	是否幂等
GET	获取资源	是
POST	创建资源	否
PUT	更新/替换资源	是
PATCH	部分更新	否
DELETE	删除资源	是
HEAD	获取响应头	是
OPTIONS	获取支持的方法	是

路由挂载 #

单个路由挂载 #

rust

#[launch]
fn rocket() -> _ {
    rocket::build().mount("/", routes![index])
}

多个路由挂载 #

rust

#[launch]
fn rocket() -> _ {
    rocket::build().mount("/", routes![
        index,
        get_resource,
        create_resource,
        update_resource,
        delete_resource
    ])
}

多个挂载点 #

rust

#[launch]
fn rocket() -> _ {
    rocket::build()
        .mount("/", routes![index, about])
        .mount("/api/users", routes![get_users, create_user])
        .mount("/api/posts", routes![get_posts, create_post])
}

路由优先级 #

当多个路由匹配同一请求时，Rocket按以下规则确定优先级：

静态路径优先于动态路径
更具体的路径优先
声明顺序影响相同优先级的路由

rust

#[get("/users/new")]
fn new_user() -> &'static str {
    "New user form"
}

#[get("/users/<id>")]
fn get_user(id: &str) -> String {
    format!("User: {}", id)
}

访问 /users/new 会匹配 new_user，而不是 get_user。

路由重定向 #

永久重定向 #

rust

use rocket::response::Redirect;

#[get("/old-path")]
fn old_path() -> Redirect {
    Redirect::permanent("/new-path")
}

#[get("/new-path")]
fn new_path() -> &'static str {
    "New location"
}

临时重定向 #

rust

#[get("/temp")]
fn temp_redirect() -> Redirect {
    Redirect::to("/target")
}

路由组 #

使用模块组织相关路由：

rust

mod api {
    mod users {
        #[get("/")]
        pub fn list() -> &'static str {
            "List users"
        }

        #[get("/<id>")]
        pub fn get(id: u32) -> String {
            format!("User {}", id)
        }
    }

    mod posts {
        #[get("/")]
        pub fn list() -> &'static str {
            "List posts"
        }
    }
}

#[launch]
fn rocket() -> _ {
    rocket::build()
        .mount("/api/users", routes![api::users::list, api::users::get])
        .mount("/api/posts", routes![api::posts::list])
}

路由元数据 #

获取请求信息 #

rust

use rocket::http::{Method, ContentType};
use rocket::request::Request;

#[get("/info")]
fn info(request: &Request) -> String {
    format!(
        "Method: {}\nPath: {}\nContent-Type: {:?}",
        request.method(),
        request.uri().path(),
        request.content_type()
    )
}

条件路由 #

使用 rank 属性设置路由优先级：

rust

#[get("/user/<id>", rank = 2)]
fn user_by_id(id: u32) -> String {
    format!("User by ID: {}", id)
}

#[get("/user/<name>", rank = 1)]
fn user_by_name(name: &str) -> String {
    format!("User by name: {}", name)
}

路由匹配规则 #

精确匹配 #

rust

#[get("/exact/path")]
fn exact_match() -> &'static str {
    "Exact match"
}

尾部斜杠 #

Rocket默认不区分尾部斜杠：

rust

#[get("/path")]
fn path() -> &'static str {
    "Matches /path and /path/"
}

索引路由 #

rust

#[get("/")]
fn index() -> &'static str {
    "Index page"
}

#[get("/users/")]
fn users_index() -> &'static str {
    "Users index"
}

路由调试 #

查看所有路由 #

启动时Rocket会打印所有注册的路由：

text

🛰  Routes:
   >> (index) GET /
   >> (get_users) GET /api/users
   >> (create_user) POST /api/users

路由冲突检测 #

Rocket会在编译时检测路由冲突：

rust

#[get("/same")]
fn route1() -> &'static str { "Route 1" }

#[get("/same")]
fn route2() -> &'static str { "Route 2" }

这会导致编译错误。

完整示例 #

rust

#[macro_use] extern crate rocket;

use rocket::response::Redirect;

#[get("/")]
fn index() -> &'static str {
    "Welcome to the API"
}

#[get("/about")]
fn about() -> &'static str {
    "About page"
}

#[get("/users")]
fn list_users() -> &'static str {
    "List of users"
}

#[get("/users/<id>")]
fn get_user(id: u32) -> String {
    format!("User ID: {}", id)
}

#[post("/users")]
fn create_user() -> &'static str {
    "Create user"
}

#[put("/users/<id>")]
fn update_user(id: u32) -> String {
    format!("Update user {}", id)
}

#[delete("/users/<id>")]
fn delete_user(id: u32) -> String {
    format!("Delete user {}", id)
}

#[get("/old-users")]
fn old_users() -> Redirect {
    Redirect::permanent("/users")
}

#[launch]
fn rocket() -> _ {
    rocket::build()
        .mount("/", routes![index, about])
        .mount("/api", routes![
            list_users,
            get_user,
            create_user,
            update_user,
            delete_user,
            old_users
        ])
}

下一步 #

了解了路由基础后，让我们深入学习路由属性，掌握更多路由定义的高级用法。