Function parallel_weather

databases/sqlite/src/main.rs:38–48

Version 2: Calls 4 queries in parallel, as an asynchronous handler Returning Error types turn into None values in the response

(db: web::Data<Pool>)

/// Version 2: Calls 4 queries in parallel, as an asynchronous handler
/// Returning Error types turn into None values in the response
async fn parallel_weather(db: web::Data<Pool>) -> Result<HttpResponse, AWError> {
    let fut_result = vec![
        db::execute(&db, Queries::GetTopTenHottestYears),
        db::execute(&db, Queries::GetTopTenColdestYears),
        db::execute(&db, Queries::GetTopTenHottestMonths),
        db::execute(&db, Queries::GetTopTenColdestMonths),
    ];
    let result: Result<Vec<_>, _> = join_all(fut_result).await.into_iter().collect();

    Ok(HttpResponse::Ok().json(result.map_err(AWError::from)?))
}

#[actix_web::main]
async fn main() -> io::Result<()> {