Rust - QR generator API

cargo.toml

[package]
name = "actix_qr_generator"
version = "0.1.0"
edition = "2021"

[dependencies]
actix-web = { version = "4", features = ["openssl"] } 
qrcode-generator = "4.1.8"
serde = { version = "1.0", features = ["derive"] }
serde_json = "1"
openssl = { version = "0.10" , features = ["vendored"] }

rust_qr_generator_api.rs

use actix_web::{web, post, App, HttpServer, HttpResponse, Responder};
use qrcode_generator::QrCodeEcc;
use serde::Deserialize;
use openssl::ssl::{SslAcceptor, SslFiletype, SslMethod};

#[derive(Deserialize)]
struct QrRequest {
  urlToEmbed: String,
}

#[post("/qr")]
async fn generate_qr(qr_request: web::Json<QrRequest>) -> impl Responder {
  if qr_request.urlToEmbed.is_empty() {
    return HttpResponse::BadRequest().into();
  }


  let result: Vec<u8> = qrcode_generator::to_png_to_vec(qr_request.urlToEmbed.clone(), QrCodeEcc::Low, 512)
    .unwrap();
  return HttpResponse::Ok()
    .content_type("image/png")
    .body(result);
}

#[actix_web::main]
async fn main() -> std::io::Result<()> {
  let mut builder = SslAcceptor::mozilla_intermediate(SslMethod::tls()).unwrap();
  builder
    .set_private_key_file("/Users/mayankc/Work/source/perfComparisons/certs/key.pem", SslFiletype::PEM)
    .unwrap();
  builder
    .set_certificate_chain_file("/Users/mayankc/Work/source/perfComparisons/certs/cert.pem")
    .unwrap();

  HttpServer::new(|| App::new().service(generate_qr))
    .bind_openssl("127.0.0.1:3000", builder)?
    .run()
    .await
}


// NOTE ================================================
// The app has been built in release mode.
// =====================================================