Askama - vector of structs

[package]
name = "askama-templates"
version = "0.1.0"
edition = "2024"
publish = false

[dependencies]
askama = "0.15.6"
axum = "0.8.8"
serde = { version = "1.0.228", features = ["derive"] }
tokio = { version = "1.50.0", features = ["full"] }

[dev-dependencies]
headers = "0.4.1"
http-body-util = "0.1.3"
tower = { version = "0.5.3", features = ["util"] }

use askama::Template;
use axum::{
    Router,
    http::StatusCode,
    response::{Html, IntoResponse, Response},
    routing::get,
};

struct Planet {
    name: String,
    distance: f64,
    mass: f64,
}

struct HtmlTemplate<T>(T);

impl<T> IntoResponse for HtmlTemplate<T>
where
    T: Template,
{
    fn into_response(self) -> Response {
        match self.0.render() {
            Ok(html) => Html(html).into_response(),
            Err(err) => (
                StatusCode::INTERNAL_SERVER_ERROR,
                format!("Failed to render template. Error: {err}"),
            )
                .into_response(),
        }
    }
}

#[derive(Template)]
#[template(path = "main.html")]
struct MainTemplate {
    planets: Vec<Planet>,
}

async fn main_page() -> impl IntoResponse {
    let planets = vec![
        Planet {
            name: String::from("Mercury"),
            distance: 0.4,
            mass: 0.055,
        },
        Planet {
            name: String::from("Venus"),
            distance: 0.7,
            mass: 0.815,
        },
        Planet {
            name: String::from("Earth"),
            distance: 1.0,
            mass: 1.0,
        },
    ];

    let template = MainTemplate { planets: planets };
    HtmlTemplate(template)
}

fn create_router() -> Router {
    Router::new().route("/", get(main_page))
}
#[tokio::main]
async fn main() {
    let listener = tokio::net::TcpListener::bind("127.0.0.1:3000")
        .await
        .unwrap();
    println!("listening on {}", listener.local_addr().unwrap());
    axum::serve(listener, create_router()).await.unwrap();
}

#[cfg(test)]
mod tests;

#![allow(unused)]
fn main() {
use super::*;
use axum::{
    body::Body,
    http::{Request, StatusCode},
};
use http_body_util::BodyExt;
use tower::ServiceExt;

#[tokio::test]
async fn test_main() {
    let response = create_router()
        .oneshot(Request::builder().uri("/").body(Body::empty()).unwrap())
        .await
        .unwrap();
    assert_eq!(response.status(), StatusCode::OK);

    let content_type = response.headers().get("content-type").unwrap();
    assert_eq!(content_type.to_str().unwrap(), "text/html; charset=utf-8");

    let body = response.into_body();
    let bytes = body.collect().await.unwrap().to_bytes();
    let html = String::from_utf8(bytes.to_vec()).unwrap();

    assert!(html.contains(r#"<h1>Planets</h1>"#));
}
}

<h1>Planets</h1>

<table>
{% for planet in planets %}
   <tr><td>{{planet.name}}</td><td>{{planet.distance}}</td><td>{{planet.mass}}</td></tr>
{% endfor %}
</table>

<style>
td {
    padding: 10px;
}
</style>