Rocket snippet for a short talk of how to use Rocket

Rocket snippet

Rocket

Intro
- Primitives to build web servers
- Routing (params and handlers)
- Validation
- Error Handling
- Pre-Processing of requests
- Post-processing of responses

Setup Rust
curl https://sh.rustup.rs -sSf | sh
or windows
- rustup show
- rustup update && cargo update
- rustup override set nightly (at the project dir)

Setup Rocket 
- cargo new hello-rocket --bin
- cd hello-rocket
- rocket = “0.4.1”

First Hello World
- Code
#![feature(proc_macro_hygiene, decl_macro)]

#[macro_use] extern crate rocket;

#[get("/")]
fn index() -> &'static str {
    "Hello, world!"
}

fn main() {
    rocket::ignite().mount("/", routes![index]).launch();
}

- Add more endpoints GET and POST
curl -d "param=ok" -X POST http://localhost:8000/app/postSmt

- Modules and namespace
mod other {
  pub fn test() -> &’static str {“X”}
}
Rocket::ignite().mount(“/“, routes![other::test]);

- API
// #![feature(plugin)]
// #![plugin(rocket_codegen)]

#[derive(Debug)]
struct LoadAvg {
    last: f64,  // last minute load average
    last5: f64,  // last 5 minutes load average
    last15: f64  // last 15 minutes load average
}
impl LoadAvg {
    fn new() -> LoadAvg {
        // Placeholder
        LoadAvg {
            last: 0.9,
            last5: 1.5,
            last15: 1.8
        }
    }
}

main()
    let load_avg = LoadAvg::new();
    println!("{:?}", load_avg);

- JSON
[dependencies]
rocket_contrib = { version = "0.4.1", features = ["json"] }
serde = "1.0.91"
serde_json = "1.0.39"
serde_derive = "1.0.91"

extern crate serde_json;
#[macro_use] extern crate rocket_contrib;
#[macro_use] extern crate serde_derive;
use rocket_contrib::JSON;

#[derive(Serialize)]
struct LoadAvg {}

#[get("/loadavg")]
fn loadavg() -> JSON<LoadAvg> {
    JSON(LoadAvg::new())
}