Support asynchronous data factories #850

CHANGES.md

@@ -2,10 +2,15 @@
 
 ## [1.0.3] - unreleased
 
+### Added
+
+* Support asynchronous data factories #850
+
 ### Changed
 
 *  Use `encoding_rs` crate instead of unmaintained `encoding` crate
 
+
 ## [1.0.2] - 2019-06-17
 
 ### Changed
@@ -17,7 +22,7 @@
 
 ## [1.0.1] - 2019-06-17
 
-### Add
+### Added
 
 * Add support for PathConfig #903
 
@@ -42,7 +47,7 @@
 
 ## [1.0.0] - 2019-06-05
 
-### Add
+### Added
 
 * Add `Scope::configure()` method.
 

src/app.rs

@@ -8,7 +8,7 @@ use actix_service::boxed::{self, BoxedNewService};
 use actix_service::{
     apply_transform, IntoNewService, IntoTransform, NewService, Transform,
 };
-use futures::IntoFuture;
+use futures::{Future, IntoFuture};
 
 use crate::app_service::{AppEntry, AppInit, AppRoutingFactory};
 use crate::config::{AppConfig, AppConfigInner, ServiceConfig};
@@ -23,6 +23,7 @@ use crate::service::{
 };
 
 type HttpNewService = BoxedNewService<(), ServiceRequest, ServiceResponse, Error, ()>;
+type FnDataFactory = Box<Fn() -> Box<dyn Future<Item = Box<DataFactory>, Error = ()>>>;
 
 /// Application builder - structure that follows the builder pattern
 /// for building application instances.
@@ -32,6 +33,7 @@ pub struct App<T, B> {
     default: Option<Rc<HttpNewService>>,
     factory_ref: Rc<RefCell<Option<AppRoutingFactory>>>,
     data: Vec<Box<DataFactory>>,
+    data_factories: Vec<FnDataFactory>,
     config: AppConfigInner,
     external: Vec<ResourceDef>,
     _t: PhantomData<(B)>,
@@ -44,6 +46,7 @@ impl App<AppEntry, Body> {
         App {
             endpoint: AppEntry::new(fref.clone()),
             data: Vec::new(),
+            data_factories: Vec::new(),
             services: Vec::new(),
             default: None,
             factory_ref: fref,
@@ -100,6 +103,31 @@ where
         self
     }
 
+    /// Set application data factory. This function is
+    /// similar to `.data()` but it accepts data factory. Data object get
+    /// constructed asynchronously during application initialization.
+    pub fn data_factory<F, Out>(mut self, data: F) -> Self
+    where
+        F: Fn() -> Out + 'static,
+        Out: IntoFuture + 'static,
+        Out::Error: std::fmt::Debug,
+    {
+        self.data_factories.push(Box::new(move || {
+            Box::new(
+                data()
+                    .into_future()
+                    .map_err(|e| {
+                        log::error!("Can not construct data instance: {:?}", e);
+                    })
+                    .map(|data| {
+                        let data: Box<dyn DataFactory> = Box::new(Data::new(data));
+                        data
+                    }),
+            )
+        }));
+        self
+    }
+
     /// Set application data. Application data could be accessed
     /// by using `Data<T>` extractor where `T` is data type.
     pub fn register_data<U: 'static>(mut self, data: Data<U>) -> Self {
@@ -349,6 +377,7 @@ where
         App {
             endpoint,
             data: self.data,
+            data_factories: self.data_factories,
             services: self.services,
             default: self.default,
             factory_ref: self.factory_ref,
@@ -423,6 +452,7 @@ where
     fn into_new_service(self) -> AppInit<T, B> {
         AppInit {
             data: Rc::new(self.data),
+            data_factories: Rc::new(self.data_factories),
             endpoint: self.endpoint,
             services: Rc::new(RefCell::new(self.services)),
             external: RefCell::new(self.external),
@@ -490,24 +520,24 @@ mod tests {
         assert_eq!(resp.status(), StatusCode::CREATED);
     }
 
-    // #[test]
+    #[test]
-    // fn test_data_factory() {
+    fn test_data_factory() {
-    //     let mut srv =
+        let mut srv =
-    //         init_service(App::new().data_factory(|| Ok::<_, ()>(10usize)).service(
+            init_service(App::new().data_factory(|| Ok::<_, ()>(10usize)).service(
-    //             web::resource("/").to(|_: web::Data<usize>| HttpResponse::Ok()),
+                web::resource("/").to(|_: web::Data<usize>| HttpResponse::Ok()),
-    //         ));
+            ));
-    //     let req = TestRequest::default().to_request();
+        let req = TestRequest::default().to_request();
-    //     let resp = block_on(srv.call(req)).unwrap();
+        let resp = block_on(srv.call(req)).unwrap();
-    //     assert_eq!(resp.status(), StatusCode::OK);
+        assert_eq!(resp.status(), StatusCode::OK);
 
-    //     let mut srv =
+        let mut srv =
-    //         init_service(App::new().data_factory(|| Ok::<_, ()>(10u32)).service(
+            init_service(App::new().data_factory(|| Ok::<_, ()>(10u32)).service(
-    //             web::resource("/").to(|_: web::Data<usize>| HttpResponse::Ok()),
+                web::resource("/").to(|_: web::Data<usize>| HttpResponse::Ok()),
-    //         ));
+            ));
-    //     let req = TestRequest::default().to_request();
+        let req = TestRequest::default().to_request();
-    //     let resp = block_on(srv.call(req)).unwrap();
+        let resp = block_on(srv.call(req)).unwrap();
-    //     assert_eq!(resp.status(), StatusCode::INTERNAL_SERVER_ERROR);
+        assert_eq!(resp.status(), StatusCode::INTERNAL_SERVER_ERROR);
-    // }
+    }
 
     fn md<S, B>(
         req: ServiceRequest,

src/app_service.rs

@@ -25,6 +25,7 @@ type BoxedResponse = Either<
     FutureResult<ServiceResponse, Error>,
     Box<Future<Item = ServiceResponse, Error = Error>>,
 >;
+type FnDataFactory = Box<Fn() -> Box<dyn Future<Item = Box<DataFactory>, Error = ()>>>;
 
 /// Service factory to convert `Request` to a `ServiceRequest<S>`.
 /// It also executes data factories.
@@ -40,6 +41,7 @@ where
 {
     pub(crate) endpoint: T,
     pub(crate) data: Rc<Vec<Box<DataFactory>>>,
+    pub(crate) data_factories: Rc<Vec<FnDataFactory>>,
     pub(crate) config: RefCell<AppConfig>,
     pub(crate) services: Rc<RefCell<Vec<Box<ServiceFactory>>>>,
     pub(crate) default: Option<Rc<HttpNewService>>,
@@ -119,16 +121,12 @@ where
         let rmap = Rc::new(rmap);
         rmap.finish(rmap.clone());
 
-        // create app data container
-        let mut data = Extensions::new();
-        for f in self.data.iter() {
-            f.create(&mut data);
-        }
-
         AppInitResult {
             endpoint: None,
             endpoint_fut: self.endpoint.new_service(&()),
-            data: Rc::new(data),
+            data: self.data.clone(),
+            data_factories: Vec::new(),
+            data_factories_fut: self.data_factories.iter().map(|f| f()).collect(),
             config,
             rmap,
             _t: PhantomData,
@@ -144,7 +142,9 @@ where
     endpoint_fut: T::Future,
     rmap: Rc<ResourceMap>,
     config: AppConfig,
-    data: Rc<Extensions>,
+    data: Rc<Vec<Box<DataFactory>>>,
+    data_factories: Vec<Box<DataFactory>>,
+    data_factories_fut: Vec<Box<dyn Future<Item = Box<DataFactory>, Error = ()>>>,
     _t: PhantomData<B>,
 }
 
@@ -159,21 +159,43 @@ where
     >,
 {
     type Item = AppInitService<T::Service, B>;
-    type Error = T::InitError;
+    type Error = ();
 
     fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+        // async data factories
+        let mut idx = 0;
+        while idx < self.data_factories_fut.len() {
+            match self.data_factories_fut[idx].poll()? {
+                Async::Ready(f) => {
+                    self.data_factories.push(f);
+                    self.data_factories_fut.remove(idx);
+                }
+                Async::NotReady => idx += 1,
+            }
+        }
+
         if self.endpoint.is_none() {
             if let Async::Ready(srv) = self.endpoint_fut.poll()? {
                 self.endpoint = Some(srv);
             }
         }
 
-        if self.endpoint.is_some() {
+        if self.endpoint.is_some() && self.data_factories_fut.is_empty() {
+            // create app data container
+            let mut data = Extensions::new();
+            for f in self.data.iter() {
+                f.create(&mut data);
+            }
+
+            for f in &self.data_factories {
+                f.create(&mut data);
+            }
+
             Ok(Async::Ready(AppInitService {
                 service: self.endpoint.take().unwrap(),
                 rmap: self.rmap.clone(),
                 config: self.config.clone(),
-                data: self.data.clone(),
+                data: Rc::new(data),
                 pool: HttpRequestPool::create(),
             }))
         } else {