Rocket - Path parameters

---

Instead of passing parameters in the Query string in a GET request we can also use the path to pass parameters. This is especially interesgint if we would like to make the pages indexable by search engines.

• e.g. in a blog engine the path can be mapped to a blog entry
• In a social site we might want to have a separate page for each users.

examples/rocket/path-parameters/src/main.rs

#[macro_use]
extern crate rocket;

use rocket::response::content;

#[get("/")]
fn index() -> content::RawHtml<String> {
    let html = String::from(
        r#"
    <a href="/user/42">User 42</a><br>
    <a href="/user/foo">User foo - not valid</a><br>
    "#,
    );

    content::RawHtml(html)
}

#[get("/user/<uid>")]
fn user(uid: usize) -> content::RawHtml<String> {
    let html = format!("User ID: {uid}");
    content::RawHtml(html)
}

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

#[cfg(test)]
mod tests;

examples/rocket/path-parameters/src/tests.rs

use rocket::http::Status;
use rocket::local::blocking::Client;

#[test]
fn main_page() {
    let client = Client::tracked(super::rocket()).unwrap();
    let response = client.get("/").dispatch();

    assert_eq!(response.status(), Status::Ok);
    assert_eq!(
        response.headers().get_one("Content-Type").unwrap(),
        "text/html; charset=utf-8"
    );
    let html = response.into_string().unwrap();
    assert!(html.contains(r#"<a href="/user/42">User 42</a><br>"#));
}

#[test]
fn valid_user() {
    let client = Client::tracked(super::rocket()).unwrap();
    let response = client.get("/user/42").dispatch();

    assert_eq!(response.status(), Status::Ok);
    assert_eq!(
        response.headers().get_one("Content-Type").unwrap(),
        "text/html; charset=utf-8"
    );
    let html = response.into_string().unwrap();
    assert_eq!(html, "User ID: 42");
}

#[test]
fn invalid_user() {
    let client = Client::tracked(super::rocket()).unwrap();
    let response = client.get("/user/foo").dispatch();

    assert_eq!(response.status(), Status::UnprocessableEntity); // 422
}