Rust SDK

Send email with Rocket

Use Parcel Wing from Rocket routes with managed state and JSON requests.

Install the SDK

The official Rust SDK is published as parcelwing.

Terminal

cargo add parcelwing
cargo add tokio --features macros,rt-multi-thread

Rocket route

Create the Parcel Wing client during server startup, then call it from trusted async handlers.

src/main.rs

use parcelwing::{Client, EmailSendRequest};
use rocket::{post, routes, serde::json::Json, State};
use rocket::serde::{Deserialize, Serialize};
 
#[derive(Deserialize)]
#[serde(crate = "rocket::serde")]
struct WelcomeRequest {
    email: String,
    first_name: Option<String>,
}
 
#[derive(Serialize)]
#[serde(crate = "rocket::serde")]
struct SendResponse {
    id: String,
}
 
#[post("/send-welcome", data = "<payload>")]
async fn send_welcome(
    client: &State<Client>,
    payload: Json<WelcomeRequest>,
) -> Result<Json<SendResponse>, String> {
    let emails = client
        .emails()
        .send(
            EmailSendRequest::new(std::env::var("PARCELWING_FROM_EMAIL").unwrap(), payload.email.clone())
                .template_alias("welcome")
                .template_param("first_name", payload.first_name.clone().unwrap_or_else(|| "friend".to_string())),
        )
        .await
        .map_err(|error| error.to_string())?;
 
    Ok(Json(SendResponse { id: emails[0].id.clone() }))
}
 
#[rocket::main]
async fn main() -> Result<(), rocket::Error> {
    let client = Client::new(std::env::var("PARCELWING_API_KEY").unwrap()).unwrap();
 
    rocket::build()
        .manage(client)
        .mount("/", routes![send_welcome])
        .launch()
        .await?;
 
    Ok(())
}

Production notes

Keep PARCELWING_API_KEY in server-side environment variables.
Build one SDK client during server startup and reuse it from trusted handlers.
Log parcelwing::Error::Api details for support and debugging.