use std::collections::HashMap; use actix_http::{body::Body, Response}; use actix_web::dev::ServiceResponse; use actix_web::http::StatusCode; use actix_web::middleware::errhandlers::{ErrorHandlerResponse, ErrorHandlers}; use actix_web::{error, middleware, web, App, Error, HttpResponse, HttpServer, Result}; use serde_json::json; use tinytemplate::TinyTemplate; // store tiny_template in application state async fn index( tmpl: web::Data>, query: web::Query>, ) -> Result { let s = if let Some(name) = query.get("name") { // submitted form let ctx = json!({ "name" : name.to_owned(), "text" : "Welcome!".to_owned() }); tmpl.render("user.html", &ctx) .map_err(|_| error::ErrorInternalServerError("Template error"))? } else { tmpl.render("index.html", &serde_json::Value::Null) .map_err(|_| error::ErrorInternalServerError("Template error"))? }; Ok(HttpResponse::Ok().content_type("text/html").body(s)) } #[actix_rt::main] async fn main() -> std::io::Result<()> { std::env::set_var("RUST_LOG", "actix_web=info"); env_logger::init(); HttpServer::new(|| { let mut tt = TinyTemplate::new(); tt.add_template("index.html", INDEX).unwrap(); tt.add_template("user.html", USER).unwrap(); tt.add_template("error.html", ERROR).unwrap(); App::new() .data(tt) .wrap(middleware::Logger::default()) // enable logger .service(web::resource("/").route(web::get().to(index))) .service(web::scope("").wrap(error_handlers())) }) .bind("127.0.0.1:8080")? .run() .await } // Custom error handlers, to return HTML responses when an error occurs. fn error_handlers() -> ErrorHandlers { ErrorHandlers::new().handler(StatusCode::NOT_FOUND, not_found) } // Error handler for a 404 Page not found error. fn not_found(res: ServiceResponse) -> Result> { let response = get_error_response(&res, "Page not found"); Ok(ErrorHandlerResponse::Response( res.into_response(response.into_body()), )) } // Generic error handler. fn get_error_response(res: &ServiceResponse, error: &str) -> Response { let request = res.request(); // Provide a fallback to a simple plain text response in case an error occurs during the // rendering of the error page. let fallback = |e: &str| { Response::build(res.status()) .content_type("text/plain") .body(e.to_string()) }; let tt = request .app_data::>>() .map(|t| t.get_ref()); match tt { Some(tt) => { let mut context = std::collections::HashMap::new(); context.insert("error", error.to_owned()); context.insert("status_code", res.status().as_str().to_owned()); let body = tt.render("error.html", &context); match body { Ok(body) => Response::build(res.status()) .content_type("text/html") .body(body), Err(_) => fallback(error), } } None => fallback(error), } } static ERROR: &str = include_str!("../templates/error.html"); static INDEX: &str = include_str!("../templates/index.html"); static USER: &str = include_str!("../templates/user.html");