feat: implement CORS support with configuration options and middleware integration

apps/api/Cargo.toml

@@ -27,4 +27,5 @@ once_cell = { version = "1.21.3" }
 argon2 = { version = "0.5.3", features = ["std"] }
 jsonwebtoken = { version = "10.2.0", features = ["rust_crypto"] }
 uuid = { version = "1.19.0", features = ["v4", "serde", "fast-rng"] }
+tower-http = { version = "0.6.8", features = ["cors"] }
 

apps/api/src/cmd/start_server.rs

@@ -88,8 +88,10 @@ pub async fn start_server() {
 
     // build the axum app and run the server...
     info!("Starting application...");
-    let mut app: Router =
-        routes::get_root_router(Arc::new(get_app_state(&db_connection, &settings)));
+    let mut app: Router = routes::get_root_router(
+        Arc::new(get_app_state(&db_connection, &settings)),
+        Arc::new(settings.server.cors.clone()),
+    );
 
     if settings.server.serve_openapi {
         info!("Enabling OpenAPI documentation endpoint at /openapi.json");

apps/api/src/configs/key.rs

@@ -4,6 +4,7 @@ pub(crate) const LOGGING_UTC_KEY: &str = "LOGGING.UTC";
 pub(crate) const SERVER_ADDRESS_KEY: &str = "SERVER.ADDRESS";
 pub(crate) const SERVER_PORT_KEY: &str = "SERVER.PORT";
 pub(crate) const SERVER_SERVE_OPENAPI_KEY: &str = "SERVER.SERVE_OPENAPI";
+pub(crate) const SERVER_CORS_ALLOWED_ORIGINS_KEY: &str = "SERVER.CORS.ALLOWED_ORIGINS";
 //
 pub(crate) const DATABASE_URL_KEY: &str = "DATABASE.URL";
 pub(crate) const DATABASE_MAX_CONNECTIONS_KEY: &str = "DATABASE.MAX_CONNECTIONS";

apps/api/src/configs/server.rs

@@ -3,7 +3,7 @@ use std::net::IpAddr;
 use config::{Config, ConfigError};
 use tracing::warn;
 
-use crate::configs::key::SERVER_SERVE_OPENAPI_KEY;
+use crate::configs::key::{SERVER_CORS_ALLOWED_ORIGINS_KEY, SERVER_SERVE_OPENAPI_KEY};
 
 use super::{
     FromConfig,
@@ -15,6 +15,12 @@ pub struct ServerSettings {
     pub address: IpAddr,
     pub port: u16,
     pub serve_openapi: bool,
+    pub cors: CORSSettings,
+}
+
+#[derive(Debug, Clone)]
+pub struct CORSSettings {
+    pub allowed_origins: Vec<String>,
 }
 
 impl FromConfig for ServerSettings {
@@ -57,6 +63,24 @@ impl FromConfig for ServerSettings {
                     );
                     DEFAULT_SERVE_OPENAPI
                 }),
+
+            cors: CORSSettings {
+                allowed_origins: _config
+                    .get_array(SERVER_CORS_ALLOWED_ORIGINS_KEY)
+                    .unwrap_or_else(|_| vec![])
+                    .into_iter()
+                    .filter_map(|val| match val.into_string() {
+                        Ok(s) => Some(s),
+                        Err(e) => {
+                            warn!(
+                                "Invalid origin in {} configuration: {}",
+                                SERVER_CORS_ALLOWED_ORIGINS_KEY, e
+                            );
+                            None
+                        }
+                    })
+                    .collect(),
+            },
         })
     }
 

apps/api/src/middlewares.rs

@@ -6,25 +6,55 @@ use std::{sync::Arc, time::Duration};
 use axum::{
     BoxError, Router,
     error_handling::HandleErrorLayer,
-    http::{Method, StatusCode, Uri},
+    http::{HeaderValue, Method, StatusCode, Uri},
 };
 use tower::{ServiceBuilder, timeout::TimeoutLayer};
+use tower_http::cors::{AllowHeaders, AllowOrigin, CorsLayer};
 use tracing::warn;
 
-use crate::routes::AppState;
+use crate::{configs::server::CORSSettings, routes::AppState};
 
 pub const TIMEOUT_DURATION_SECS: u64 = 30;
 
-pub fn apply_root_middleware(router: Router, _state: Arc<AppState>) -> Router {
+pub fn apply_root_middleware(
+    router: Router,
+    _state: Arc<AppState>,
+    cors_settings: Arc<CORSSettings>,
+) -> Router {
     let timeout_layer = TimeoutLayer::new(Duration::from_secs(TIMEOUT_DURATION_SECS));
 
     let service_builder = ServiceBuilder::new()
         .layer(HandleErrorLayer::new(handle_timeout_error))
-        .layer(timeout_layer);
+        .layer(timeout_layer)
+        .layer(get_cors_layer(cors_settings));
 
     router.layer(service_builder)
 }
 
+pub fn get_cors_layer(cors_settings: Arc<CORSSettings>) -> CorsLayer {
+    let mut cors_layer = CorsLayer::new()
+        .allow_credentials(true)
+        .allow_headers(AllowHeaders::mirror_request());
+
+    let allowed_origins = &cors_settings.allowed_origins;
+    if allowed_origins.contains(&"*".to_string()) {
+        cors_layer = cors_layer.allow_origin(AllowOrigin::mirror_request());
+        warn!(
+            "Wildcard origin is found in allowed origins. CORS is configured to allow requests from any origin. Only use this setting in development or if you understand the security implications."
+        );
+    } else {
+        for origin in allowed_origins {
+            if let Ok(header_value) = HeaderValue::from_str(origin) {
+                cors_layer = cors_layer.allow_origin(AllowOrigin::exact(header_value));
+            } else {
+                warn!("Invalid CORS origin: {}", origin);
+            }
+        }
+    }
+
+    cors_layer
+}
+
 pub async fn handle_timeout_error(
     method: Method,
     uri: Uri,

apps/api/src/routes.rs

@@ -9,6 +9,7 @@ use axum::{Extension, Router};
 use migration::sea_orm::DatabaseConnection;
 
 use crate::{
+    configs::server::CORSSettings,
     middlewares,
     services::{
         auth::{
@@ -46,7 +47,10 @@ pub struct AppService {
     pub server_state: ServiceState<dyn ServerStateStore>,
 }
 
-pub fn get_root_router(state: impl Into<Arc<AppState>>) -> Router {
+pub fn get_root_router(
+    state: impl Into<Arc<AppState>>,
+    cors_settings: Arc<CORSSettings>,
+) -> Router {
     let mut router = Router::new();
     let state = state.into();
 
@@ -54,7 +58,7 @@ pub fn get_root_router(state: impl Into<Arc<AppState>>) -> Router {
         .nest("/api", api::get_api_router(state.clone()))
         .merge(view::get_view_router());
 
-    router = middlewares::apply_root_middleware(router, state.clone());
+    router = middlewares::apply_root_middleware(router, state.clone(), cors_settings);
 
     router = router.layer(Extension(state.clone()));