feat: fixup "setup seaorm and a first "debug" entity as example"

crates/backend/Cargo.toml

@@ -7,11 +7,21 @@ edition = "2021"
 anyhow = "1.0.89"
 axum = "0.7.6"
 listenfd = "1.0.1"
-thiserror.workspace = true
 tokio = { version = "1.40.0", features = ["macros", "rt-multi-thread"] }
 
+sea-orm = { workspace = true, features = [
+    # Same `ASYNC_RUNTIME` and `DATABASE_DRIVER` as in the migration crate
+    "sqlx-sqlite",
+    "runtime-tokio-rustls",
+    "macros",
+] }
+thiserror.workspace = true
+
+entity = { path = "../../entity" }
+migration = { path = "../../migration" }
 utils = { path = "../utils" }
 
 [dev-dependencies]
 cargo-watch = "8.5.2"
+sea-orm-cli.workspace = true
 systemfd = "0.4.3"

crates/backend/README.md

@@ -10,6 +10,15 @@ En développement, le mécanisme de hot-reload nécessite de disposer de `cargo-
 cargo install cargo-watch systemfd
 ```
 
+## Configuration
+
+> Astuce : lorsqu'on exécute directement la crate `backend` à des fins de développement, le système de configuration n'utilisera pas l'éventuel fichier `.env` situé à la racine du workspace Rust. Pour éviter de dupliquer le fichier `.env`, il est possible de créer un lien symbolique vers le fichier `.env` de la crate `backend` :
+
+```bash
+cd crates/backend
+ln -s ../../.env .env
+```
+
 ## Développement
 
 Pour lancer le serveur en mode développement, exécutez la commande suivante :

crates/backend/src/db.rs

@@ -0,0 +1,11 @@
+use migration::{Migrator, MigratorTrait};
+use sea_orm::{Database, DatabaseConnection, DbErr};
+use std::env;
+
+pub async fn get_connection() -> Result<DatabaseConnection, DbErr> {
+    let database_url = env::var("DATABASE_URL").expect("DATABASE_URL must be set");
+
+    let db_connection = Database::connect(database_url).await?;
+    Migrator::up(&db_connection, None).await?;
+    Ok(db_connection)
+}

crates/backend/src/lib.rs

@@ -2,10 +2,13 @@ use anyhow::Error as AnyError;
 use axum::http::{StatusCode, Uri};
 use axum::response::{IntoResponse, Response};
 use axum::{routing::get, Router};
+use sea_orm::{DatabaseConnection, DbErr};
 use thiserror::Error;
 
 use ::utils::config::{load_config, ConfigError};
 
+mod db;
+
 #[derive(Error, Debug)]
 pub enum InitError {
     #[error(transparent)]
@@ -17,10 +20,17 @@ pub fn init() -> Result<(), InitError> {
     Ok(())
 }
 
-pub fn get_router() -> Router {
-    Router::new()
+#[derive(Clone)]
+pub struct AppState {
+    db_connection: DatabaseConnection,
+}
+
+pub async fn get_router() -> Result<Router, DbErr> {
+    let db_connection = db::get_connection().await?;
+
+    Ok(Router::new()
         .route("/", get(|| async { "Hello, world!" }))
-        .fallback(fallback)
+        .fallback(fallback))
 }
 
 async fn fallback(uri: Uri) -> (StatusCode, String) {

crates/backend/src/main.rs

@@ -10,16 +10,17 @@ pub enum BackendError {
     ServeTCPListener(#[from] std::io::Error),
     #[error("Error while initialising the backend")]
     InitError(#[from] InitError),
+    #[error("Error with the database connection")]
+    DatabaseConnection(#[from] sea_orm::DbErr),
 }
 
 #[tokio::main]
 async fn main() -> Result<(), BackendError> {
     init()?;
 
-    let app = get_router();
+    let app = get_router().await?;
 
     let mut listenfd = ListenFd::from_env();
-
     let listener = match listenfd.take_tcp_listener(0)? {
         // if we are given a tcp listener on listen fd 0, we use that one
         Some(listener) => {