chore: scaffold axum server with in-memory CRUD, auth stub and tracing

Justfile

@@ -0,0 +1,7 @@
+backend_path := "backend"
+
+watch:
+    cd {{backend_path}} && cargo watch -q -c -w src/ -x run
+
+watch-test:
+    cd {{backend_path}} && cargo watch -q -c -w src/ -x test

backend/Cargo.toml

@@ -4,8 +4,15 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
-axum = "0.8.8"
+anyhow = "1.0.102"
+axum = { version = "0.8.9", features = [] }
 serde = { version = "1.0.228", features = ["derive"] }
+serde_json = "1.0.149"
 tokio = { version = "1.51.0", features = ["full"] }
+tower-http = { version = "0.6.8", features = ["fs"] }
+tower-cookies = "0.11.0"
 tracing = "0.1.44"
-tracing-subscriber = "0.3.23"
+tracing-subscriber = { version = "0.3.23", features = ["env-filter"] }
+
+[dev-dependencies]
+axum-test = "20.0.0"

backend/src/error.rs

@@ -0,0 +1,33 @@
+use std::fmt;
+
+use axum::{http::StatusCode, response::IntoResponse};
+use tracing::info;
+
+#[derive(Debug)]
+pub enum LoftError {
+    LoginFail,
+    FileIdNotFound,
+}
+
+impl fmt::Display for LoftError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{:?}", self)
+    }
+}
+
+impl std::error::Error for LoftError {}
+
+impl IntoResponse for LoftError {
+    fn into_response(self) -> axum::response::Response {
+        match self {
+            Self::LoginFail => {
+                info!("UNAUTHORIZED");
+                StatusCode::UNAUTHORIZED.into_response()
+            }
+            Self::FileIdNotFound => {
+                info!("NOT_FOUND");
+                StatusCode::NOT_FOUND.into_response()
+            }
+        }
+    }
+}

backend/src/main.rs

@@ -1,9 +1,49 @@
-use axum::{Router, routing::get};
+mod error;
+mod model;
+mod web;
 
+use anyhow::Result;
+use axum::{Router, middleware, response::Response};
+use tower_cookies::CookieManagerLayer;
+use tower_http::services::ServeDir;
+use tracing::info;
+use tracing_subscriber::{layer::SubscriberExt, util::SubscriberInitExt};
+
+use crate::{
+    model::FileController,
+    web::{routes_file::routes_file, routes_health::routes_health, routes_login::routes_login},
+};
 
 #[tokio::main]
-async fn main() {
-    let app = Router::new().route("/", get(|| async { "Hello Async!\n"}));
-    let listener = tokio::net::TcpListener::bind("0.0.0.0:3000").await.unwrap();
-    axum::serve(listener, app).await.unwrap();
+async fn main() -> Result<()> {
+    tracing_subscriber::registry()
+        .with(
+            tracing_subscriber::EnvFilter::try_from_default_env().unwrap_or_else(|_| {
+                format!("{}=info,tower_http=info", env!("CARGO_CRATE_NAME")).into()
+            }),
+        )
+        .with(tracing_subscriber::fmt::layer())
+        .init();
+
+    let file_controller = FileController::new().await?;
+
+    let app = Router::new()
+        .nest("/api", routes_file(file_controller))
+        .merge(routes_health())
+        .merge(routes_login())
+        .layer(middleware::map_response(main_response_mapper))
+        .layer(CookieManagerLayer::new())
+        .fallback_service(ServeDir::new("./"));
+
+    let listener = tokio::net::TcpListener::bind("0.0.0.0:3000").await?;
+    info!("listening on {}", listener.local_addr().unwrap());
+
+    axum::serve(listener, app).await?;
+
+    Ok(())
+}
+
+async fn main_response_mapper(res: Response) -> Response {
+    info!("response mapper: {}", res.status());
+    res
 }

backend/src/model.rs

@@ -0,0 +1,136 @@
+use std::sync::{Arc, Mutex};
+
+use serde::{Deserialize, Serialize};
+
+use crate::error::LoftError;
+
+#[derive(Clone, Debug, Serialize)]
+pub struct File {
+    pub id: u64, // make uuid
+    pub name: String,
+    pub file_type: String, // make enum
+}
+
+#[derive(Clone, Debug, Deserialize)]
+pub struct FileToCreate {
+    pub name: String,
+    pub file_type: String, // make enum
+}
+
+#[derive(Clone)]
+pub struct FileController {
+    file_storage: Arc<Mutex<Vec<Option<File>>>>,
+}
+
+impl FileController {
+    pub async fn new() -> Result<Self, LoftError> {
+        Ok(Self {
+            file_storage: Arc::default(),
+        })
+    }
+
+    pub async fn upload_file(&self, file_to_create: FileToCreate) -> Result<File, LoftError> {
+        let mut file_storage = self.file_storage.lock().unwrap();
+        let id = file_storage.len() as u64;
+        let file = File {
+            id,
+            name: file_to_create.name,
+            file_type: file_to_create.file_type,
+        };
+        file_storage.push(Some(file.clone()));
+        Ok(file)
+    }
+
+    pub async fn download_file(&self, file_id: u64) -> Result<File, LoftError> {
+        let file_storage = self.file_storage.lock().unwrap();
+        file_storage
+            .iter()
+            .flatten()
+            .find(|f| f.id == file_id)
+            .ok_or(LoftError::FileIdNotFound)
+            .cloned()
+    }
+
+    pub async fn delete_file(&self, file_id: u64) -> Result<File, LoftError> {
+        let mut file_storage = self.file_storage.lock().unwrap();
+        let file = file_storage
+            .get_mut(file_id as usize)
+            .and_then(|f| f.take());
+        file.ok_or(LoftError::FileIdNotFound)
+    }
+
+    pub async fn list_files(&self) -> Result<Vec<File>, LoftError> {
+        let file_storage = self.file_storage.lock().unwrap();
+        let files = file_storage.iter().flatten().cloned().collect();
+        Ok(files)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use anyhow::Result;
+
+    use super::*;
+
+    async fn fc() -> Result<FileController> {
+        Ok(FileController::new().await?)
+    }
+
+    fn new_file(name: &str) -> FileToCreate {
+        FileToCreate {
+            name: name.to_string(),
+            file_type: "text".to_string(),
+        }
+    }
+
+    #[tokio::test]
+    async fn test_upload_and_list() -> Result<()> {
+        let fc = fc().await?;
+        fc.upload_file(new_file("a.txt")).await?;
+        fc.upload_file(new_file("b.txt")).await?;
+        let files = fc.list_files().await?;
+        assert_eq!(files.len(), 2);
+        Ok(())
+    }
+
+    #[tokio::test]
+    async fn test_download() -> Result<()> {
+        let fc = fc().await?;
+        let uploaded = fc.upload_file(new_file("a.txt")).await?;
+        let downloaded = fc.download_file(uploaded.id).await?;
+        assert_eq!(downloaded.name, "a.txt");
+        Ok(())
+    }
+
+    #[tokio::test]
+    async fn test_download_not_found() -> Result<()> {
+        let fc = fc().await?;
+        assert!(matches!(
+            fc.download_file(99).await,
+            Err(LoftError::FileIdNotFound)
+        ));
+        Ok(())
+    }
+
+    #[tokio::test]
+    async fn test_delete() -> Result<()> {
+        let fc = fc().await?;
+        let uploaded = fc.upload_file(new_file("a.txt")).await?;
+        fc.delete_file(uploaded.id).await?;
+        assert!(matches!(
+            fc.download_file(uploaded.id).await,
+            Err(LoftError::FileIdNotFound)
+        ));
+        Ok(())
+    }
+
+    #[tokio::test]
+    async fn test_delete_not_found() -> Result<()> {
+        let fc = fc().await?;
+        assert!(matches!(
+            fc.delete_file(99).await,
+            Err(LoftError::FileIdNotFound)
+        ));
+        Ok(())
+    }
+}

backend/src/web/mod.rs

@@ -0,0 +1,3 @@
+pub mod routes_file;
+pub mod routes_health;
+pub mod routes_login;

backend/src/web/routes_file.rs

@@ -0,0 +1,132 @@
+use axum::{
+    Json, Router,
+    extract::{Path, State},
+    routing::get,
+};
+use tracing::info;
+
+use crate::{
+    error::LoftError,
+    model::{File, FileController, FileToCreate},
+};
+
+pub fn routes_file(file_controller: FileController) -> Router {
+    Router::new()
+        .route("/files", get(list_files).post(upload_file))
+        .route("/files/{id}", get(download_file).delete(delete_file))
+        .with_state(file_controller)
+}
+
+async fn upload_file(
+    State(file_controller): State<FileController>,
+    Json(file_to_create): Json<FileToCreate>,
+) -> Result<Json<File>, LoftError> {
+    info!("handler: upload_file");
+
+    let file = file_controller.upload_file(file_to_create).await?;
+    Ok(Json(file))
+}
+
+async fn download_file(
+    State(file_controller): State<FileController>,
+    Path(file_id): Path<u64>,
+) -> Result<Json<File>, LoftError> {
+    info!("handler: download_file");
+
+    let file = file_controller.download_file(file_id).await?;
+    Ok(Json(file))
+}
+
+async fn delete_file(
+    State(file_controller): State<FileController>,
+    Path(file_id): Path<u64>,
+) -> Result<Json<File>, LoftError> {
+    info!("handler: delete_file");
+
+    let file = file_controller.delete_file(file_id).await?;
+    Ok(Json(file))
+}
+
+async fn list_files(
+    State(file_controller): State<FileController>,
+    // can add a filters param here
+) -> Result<Json<Vec<File>>, LoftError> {
+    info!("handler: list_files");
+
+    let files = file_controller.list_files().await?;
+    Ok(Json(files))
+}
+
+#[cfg(test)]
+mod tests {
+    use axum_test::TestServer;
+    use serde_json::json;
+
+    use crate::{model::FileController, web::routes_file::routes_file};
+
+    async fn test_server() -> TestServer {
+        let fc = FileController::new().await.unwrap();
+        TestServer::new(routes_file(fc))
+    }
+
+    #[tokio::test]
+    async fn test_list_files_empty() {
+        let server = test_server().await;
+        server
+            .get("/files")
+            .await
+            .assert_status_ok()
+            .assert_json(&json!([]));
+    }
+
+    #[tokio::test]
+    async fn test_upload_and_list_files() {
+        let server = test_server().await;
+        let res = server
+            .post("/files")
+            .json(&json!({"name": "a.txt", "file_type": "text"}))
+            .await;
+        res.assert_status_ok();
+        let file = res.json::<serde_json::Value>();
+        assert_eq!(file["name"], "a.txt");
+        assert_eq!(file["id"], 0);
+
+        let list = server.get("/files").await.json::<serde_json::Value>();
+        assert_eq!(list.as_array().unwrap().len(), 1);
+    }
+
+    #[tokio::test]
+    async fn test_download_file() {
+        let server = test_server().await;
+        server
+            .post("/files")
+            .json(&json!({"name": "b.txt", "file_type": "text"}))
+            .await;
+        let res = server.get("/files/0").await;
+        res.assert_status_ok();
+        assert_eq!(res.json::<serde_json::Value>()["name"], "b.txt");
+    }
+
+    #[tokio::test]
+    async fn test_download_file_not_found() {
+        let server = test_server().await;
+        server.get("/files/99").await.assert_status_not_found();
+    }
+
+    #[tokio::test]
+    async fn test_delete_file() {
+        let server = test_server().await;
+        server
+            .post("/files")
+            .json(&json!({"name": "c.txt", "file_type": "text"}))
+            .await;
+        server.delete("/files/0").await.assert_status_ok();
+        server.get("/files/0").await.assert_status_not_found();
+    }
+
+    #[tokio::test]
+    async fn test_delete_file_not_found() {
+        let server = test_server().await;
+        server.delete("/files/99").await.assert_status_not_found();
+    }
+}

backend/src/web/routes_health.rs

@@ -0,0 +1,25 @@
+use axum::{Router, routing::get};
+
+pub fn routes_health() -> Router {
+    Router::new().route("/health", get(health))
+}
+
+async fn health() -> &'static str {
+    "up"
+}
+
+#[cfg(test)]
+mod tests {
+    use axum::{Router, routing::get};
+    use axum_test::TestServer;
+
+    use crate::web::routes_health::health;
+
+    #[tokio::test]
+    async fn test_route_health() {
+        let app = Router::new().route(&"/health", get(health));
+        let server = TestServer::new(app);
+        let response = server.get("/health").await;
+        response.assert_status_ok().assert_text("up");
+    }
+}

backend/src/web/routes_login.rs

@@ -0,0 +1,101 @@
+use axum::{
+    Json, Router,
+    routing::{get, post},
+};
+use serde::Deserialize;
+use serde_json::{Value, json};
+use tower_cookies::{Cookie, Cookies};
+
+use crate::error::LoftError;
+
+pub fn routes_login() -> Router {
+    Router::new()
+        .route("/login", post(login))
+        .route("/register", get(register))
+}
+
+async fn login(
+    cookies: Cookies,
+    Json(payload): Json<LoginPayload>,
+) -> Result<Json<Value>, LoftError> {
+    //TODO: real db/auth logic
+    if payload.username != "x" || payload.password != "y" {
+        return Err(LoftError::LoginFail);
+    }
+
+    // FIXME: real auth-token generation-signature
+    cookies.add(Cookie::new("auth-token", "user-1.exp.sign"));
+
+    let body = Json(json!({
+        "result": {
+            "success": true
+        }
+    }));
+    Ok(body)
+}
+
+async fn register() -> &'static str {
+    "register"
+}
+
+#[derive(Debug, Deserialize)]
+struct LoginPayload {
+    username: String,
+    password: String,
+}
+
+#[cfg(test)]
+mod tests {
+    use axum::{
+        Router,
+        routing::{get, post},
+    };
+    use axum_test::TestServer;
+    use serde_json::json;
+
+    use crate::web::routes_login::{login, register};
+
+    #[tokio::test]
+    async fn test_routes_login_wrong_credentials() {
+        let app = Router::new()
+            .route(&"/login", post(login))
+            .layer(tower_cookies::CookieManagerLayer::new());
+        let server = TestServer::new(app);
+        let response = server
+            .post("/login")
+            .json(&json!({
+                "username": "wrong",
+                "password": "wrong",
+            }))
+            .await;
+        response.assert_status_unauthorized();
+    }
+
+    #[tokio::test]
+    async fn test_routes_login() {
+        let app = Router::new()
+            .route(&"/login", post(login))
+            .layer(tower_cookies::CookieManagerLayer::new());
+        let server = TestServer::new(app);
+        let response = server
+            .post("/login")
+            .json(&json!({
+                "username": "x",
+                "password": "y",
+            }))
+            .await;
+        response.assert_status_ok().assert_json(&json!({
+            "result": {
+                "success": true
+            }
+        }));
+    }
+
+    #[tokio::test]
+    async fn test_routes_register() {
+        let app = Router::new().route(&"/register", get(register));
+        let server = TestServer::new(app);
+        let response = server.get("/register").await;
+        response.assert_status_ok().assert_text("register");
+    }
+}