List posts with pagination

examples/actix_example/.env

@@ -1 +1,3 @@
+HOST=127.0.0.1
+PORT=5000
 DATABASE_URL="mysql://root:@localhost/rocket_example"

examples/actix_example/Cargo.toml

@@ -17,6 +17,7 @@ actix-web = "3"
 actix-files = "0.5"
 tera = "1.8.0"
 dotenv = "0.15"
+listenfd = "0.3.3"
 
 # remove `path = ""` in your own project
 sea-orm = { path = "../../", version = "^0.2", features = [

examples/actix_example/README.md

@@ -1 +1,8 @@
 # Actix with SeaORM example app
+
+Rus server with auto-reloading:
+
+```bash
+cargo install systemfd
+systemfd --no-pid -s http::5000 -- cargo watch -x run
+```

examples/actix_example/src/main.rs

@@ -5,37 +5,56 @@ 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, get, middleware, post, web, App, Error, HttpResponse, HttpServer, Result};
-
+use actix_web::{
+    error, get, middleware, post, web, App, Error, HttpRequest, HttpResponse, HttpServer, Result,
+};
+use listenfd::ListenFd;
+use sea_orm::query::*;
+use sea_orm::DatabaseConnection;
+use sea_orm::EntityTrait;
+use serde::Deserialize;
+use std::env;
 use tera::Tera;
 
 mod post;
 pub use post::Entity as Post;
-use sea_orm::query::*;
-use sea_orm::DatabaseConnection;
-use sea_orm::EntityTrait;
-
 mod setup;
 
+const DEFAULT_POSTS_PER_PAGE: usize = 4;
+
 struct AppState {
     db_url: String,
     templates: tera::Tera,
 }
 
+#[derive(Debug, Deserialize)]
+pub struct Params {
+    page: Option<usize>,
+    posts_per_page: Option<usize>,
+}
+
 #[get("/")]
-async fn list(data: web::Data<AppState>) -> Result<HttpResponse, Error> {
+async fn list(req: HttpRequest, data: web::Data<AppState>) -> Result<HttpResponse, Error> {
     let template = &data.templates;
     let conn = sea_orm::Database::connect(&data.db_url).await.unwrap();
 
-    let posts = Post::find()
-        .all(&conn)
+    // get params
+    let params = web::Query::<Params>::from_query(req.query_string()).unwrap();
+
+    let page = params.page.unwrap_or(0);
+    let posts_per_page = params.posts_per_page.unwrap_or(DEFAULT_POSTS_PER_PAGE);
+    let paginator = Post::find().paginate(&conn, posts_per_page);
+    let num_pages = paginator.num_pages().await.ok().unwrap();
+
+    let posts = paginator
+        .fetch_page(page)
         .await
         .expect("could not retrieve posts");
-
     let mut ctx = tera::Context::new();
     ctx.insert("posts", &posts);
-    ctx.insert("page", &0);
-    ctx.insert("num_pages", &1);
+    ctx.insert("page", &page);
+    ctx.insert("posts_per_page", &posts_per_page);
+    ctx.insert("num_pages", &num_pages);
 
     let body = template
         .render("index.html.tera", &ctx)
@@ -47,12 +66,20 @@ async fn list(data: web::Data<AppState>) -> Result<HttpResponse, Error> {
 async fn main() -> std::io::Result<()> {
     std::env::set_var("RUST_LOG", "actix_web=info");
     env_logger::init();
-    let db_url = "mysql://root:@localhost/rocket_example";
+
+    // get env vars
+    dotenv::dotenv().ok();
+    let db_url = env::var("DATABASE_URL").expect("DATABASE_URL is not set in .env file");
+    let host = env::var("HOST").expect("HOST is not set in .env file");
+    let port = env::var("PORT").expect("PORT is not set in .env file");
+    let server_url = format!("{}:{}", host, port);
+
+    // create post table if not exists
     let conn = sea_orm::Database::connect(&db_url).await.unwrap();
     let _ = setup::create_post_table(&conn).await;
 
-    println!("Listening on: 127.0.0.1:8080");
-    HttpServer::new(move || {
+    let mut listenfd = ListenFd::from_env();
+    let mut server = HttpServer::new(move || {
         let templates = Tera::new(concat!(env!("CARGO_MANIFEST_DIR"), "/templates/**/*")).unwrap();
         App::new()
             .data(AppState {
@@ -61,14 +88,20 @@ async fn main() -> std::io::Result<()> {
             })
             .wrap(middleware::Logger::default()) // enable logger
             .service(fs::Files::new("/static", "./static").show_files_listing())
-            .configure(init) // init todo routes
-    })
-    .bind("127.0.0.1:8080")?
-    .run()
-    .await
+            .configure(init)
+    });
+
+    server = match listenfd.take_tcp_listener(0)? {
+        Some(listener) => server.listen(listener)?,
+        None => server.bind(&server_url)?,
+    };
+
+    println!("Starting server at {}", server_url);
+    server.run().await?;
+
+    Ok(())
 }
 
-// function that will be called on new Application to configure routes for this module
 pub fn init(cfg: &mut web::ServiceConfig) {
     cfg.service(list);
 }

examples/actix_example/templates/index.html.tera

@@ -48,9 +48,15 @@
             <td></td>
             <td>
               {% if page == 0 %} Previous {% else %}
-              <a href="/?page={{ page - 1 }}">Previous</a>
+              <a
+                href="/?page={{ page - 1 }}&posts_per_page={{ posts_per_page }}"
+                >Previous</a
+              >
               {% endif %} | {% if page == num_pages - 1 %} Next {% else %}
-              <a href="/?page={{ page + 1 }}">Next</a>
+              <a
+                href="/?page={{ page + 1 }}&posts_per_page={{ posts_per_page }}"
+                >Next</a
+              >
               {% endif %}
             </td>
             <td></td>