remove pipeline from public api (#335)

actix-service/CHANGES.md

@@ -1,6 +1,9 @@
 # Changes
 
 ## Unreleased - 2021-xx-xx
+* Removed pipeline and related structs/functions. [#335]
+
+[#335]: https://github.com/actix/actix-net/pull/335
 
 
 ## 2.0.0-beta.5 - 2021-03-15

actix-service/src/and_then.rs

@@ -11,11 +11,11 @@ use pin_project_lite::pin_project;
 
 use super::{Service, ServiceFactory};
 
-/// Service for the `and_then` combinator, chaining a computation onto the end
-/// of another service which completes successfully.
+/// Service for the `and_then` combinator, chaining a computation onto the end of another service
+/// which completes successfully.
 ///
 /// This is created by the `Pipeline::and_then` method.
-pub(crate) struct AndThenService<A, B, Req>(Rc<(A, B)>, PhantomData<Req>);
+pub struct AndThenService<A, B, Req>(Rc<(A, B)>, PhantomData<Req>);
 
 impl<A, B, Req> AndThenService<A, B, Req> {
     /// Create new `AndThen` combinator
@@ -64,7 +64,7 @@ where
 }
 
 pin_project! {
-    pub(crate) struct AndThenServiceResponse<A, B, Req>
+    pub struct AndThenServiceResponse<A, B, Req>
     where
         A: Service<Req>,
         B: Service<A::Response, Error = A::Error>,
@@ -117,7 +117,7 @@ where
 }
 
 /// `.and_then()` service factory combinator
-pub(crate) struct AndThenServiceFactory<A, B, Req>
+pub struct AndThenServiceFactory<A, B, Req>
 where
     A: ServiceFactory<Req>,
     A::Config: Clone,
@@ -200,7 +200,7 @@ where
 }
 
 pin_project! {
-    pub(crate) struct AndThenServiceFactoryResponse<A, B, Req>
+    pub struct AndThenServiceFactoryResponse<A, B, Req>
     where
         A: ServiceFactory<Req>,
         B: ServiceFactory<A::Response>,
@@ -272,7 +272,9 @@ mod tests {
     use futures_util::future::lazy;
 
     use crate::{
-        fn_factory, ok, pipeline, pipeline_factory, ready, Ready, Service, ServiceFactory,
+        fn_factory, ok,
+        pipeline::{pipeline, pipeline_factory},
+        ready, Ready, Service, ServiceFactory,
     };
 
     struct Srv1(Rc<Cell<usize>>);

actix-service/src/apply.rs

@@ -214,7 +214,11 @@ mod tests {
     use futures_util::future::lazy;
 
     use super::*;
-    use crate::{ok, pipeline, pipeline_factory, Ready, Service, ServiceFactory};
+    use crate::{
+        ok,
+        pipeline::{pipeline, pipeline_factory},
+        Ready, Service, ServiceFactory,
+    };
 
     #[derive(Clone)]
     struct Srv;

actix-service/src/ext.rs

@@ -1,8 +1,12 @@
 use crate::{
-    map::Map, map_err::MapErr, transform_err::TransformMapInitErr, Service, ServiceFactory,
-    Transform,
+    and_then::{AndThenService, AndThenServiceFactory},
+    map::Map,
+    map_err::MapErr,
+    transform_err::TransformMapInitErr,
+    IntoService, IntoServiceFactory, Service, ServiceFactory, Transform,
 };
 
+/// An extension trait for [`Service`]s that provides a variety of convenient adapters.
 pub trait ServiceExt<Req>: Service<Req> {
     /// Map this service's output to a different type, returning a new service
     /// of the resulting type.
@@ -36,10 +40,27 @@ pub trait ServiceExt<Req>: Service<Req> {
     {
         MapErr::new(self, f)
     }
+
+    /// Call another service after call to this one has resolved successfully.
+    ///
+    /// This function can be used to chain two services together and ensure that the second service
+    /// isn't called until call to the fist service have finished. Result of the call to the first
+    /// service is used as an input parameter for the second service's call.
+    ///
+    /// Note that this function consumes the receiving service and returns a wrapped version of it.
+    fn and_then<I, S1>(self, service: I) -> AndThenService<Self, S1, Req>
+    where
+        Self: Sized,
+        I: IntoService<S1, Self::Response>,
+        S1: Service<Self::Response, Error = Self::Error>,
+    {
+        AndThenService::new(self, service.into_service())
+    }
 }
 
 impl<S, Req> ServiceExt<Req> for S where S: Service<Req> {}
 
+/// An extension trait for [`ServiceFactory`]s that provides a variety of convenient adapters.
 pub trait ServiceFactoryExt<Req>: ServiceFactory<Req> {
     /// Map this service's output to a different type, returning a new service
     /// of the resulting type.
@@ -68,10 +89,27 @@ pub trait ServiceFactoryExt<Req>: ServiceFactory<Req> {
     {
         crate::map_init_err::MapInitErr::new(self, f)
     }
+
+    /// Call another service after call to this one has resolved successfully.
+    fn and_then<I, SF1>(self, factory: I) -> AndThenServiceFactory<Self, SF1, Req>
+    where
+        Self: Sized,
+        Self::Config: Clone,
+        I: IntoServiceFactory<SF1, Self::Response>,
+        SF1: ServiceFactory<
+            Self::Response,
+            Config = Self::Config,
+            Error = Self::Error,
+            InitError = Self::InitError,
+        >,
+    {
+        AndThenServiceFactory::new(self, factory.into_factory())
+    }
 }
 
 impl<SF, Req> ServiceFactoryExt<Req> for SF where SF: ServiceFactory<Req> {}
 
+/// An extension trait for [`Transform`]s that provides a variety of convenient adapters.
 pub trait TransformExt<S, Req>: Transform<S, Req> {
     /// Return a new `Transform` whose init error is mapped to to a different type.
     fn map_init_err<F, E>(self, f: F) -> TransformMapInitErr<Self, S, Req, F, E>

actix-service/src/lib.rs

@@ -38,7 +38,6 @@ pub use self::apply_cfg::{apply_cfg, apply_cfg_factory};
 pub use self::ext::{ServiceExt, ServiceFactoryExt, TransformExt};
 pub use self::fn_service::{fn_factory, fn_factory_with_config, fn_service};
 pub use self::map_config::{map_config, unit_config};
-pub use self::pipeline::{pipeline, pipeline_factory, Pipeline, PipelineFactory};
 pub use self::transform::{apply, ApplyTransform, Transform};
 
 #[allow(unused_imports)]

actix-service/src/pipeline.rs

@@ -1,3 +1,6 @@
+// TODO: see if pipeline is necessary
+#![allow(dead_code)]
+
 use core::{
     marker::PhantomData,
     task::{Context, Poll},
@@ -11,7 +14,7 @@ use crate::then::{ThenService, ThenServiceFactory};
 use crate::{IntoService, IntoServiceFactory, Service, ServiceFactory};
 
 /// Construct new pipeline with one service in pipeline chain.
-pub fn pipeline<I, S, Req>(service: I) -> Pipeline<S, Req>
+pub(crate) fn pipeline<I, S, Req>(service: I) -> Pipeline<S, Req>
 where
     I: IntoService<S, Req>,
     S: Service<Req>,
@@ -23,7 +26,7 @@ where
 }
 
 /// Construct new pipeline factory with one service factory.
-pub fn pipeline_factory<I, SF, Req>(factory: I) -> PipelineFactory<SF, Req>
+pub(crate) fn pipeline_factory<I, SF, Req>(factory: I) -> PipelineFactory<SF, Req>
 where
     I: IntoServiceFactory<SF, Req>,
     SF: ServiceFactory<Req>,
@@ -35,7 +38,7 @@ where
 }
 
 /// Pipeline service - pipeline allows to compose multiple service into one service.
-pub struct Pipeline<S, Req> {
+pub(crate) struct Pipeline<S, Req> {
     service: S,
     _phantom: PhantomData<Req>,
 }
@@ -157,7 +160,7 @@ impl<S: Service<Req>, Req> Service<Req> for Pipeline<S, Req> {
 }
 
 /// Pipeline factory
-pub struct PipelineFactory<SF, Req> {
+pub(crate) struct PipelineFactory<SF, Req> {
     factory: SF,
     _phantom: PhantomData<Req>,
 }

actix-service/src/then.rs

@@ -246,7 +246,11 @@ mod tests {
 
     use futures_util::future::lazy;
 
-    use crate::{err, ok, pipeline, pipeline_factory, ready, Ready, Service, ServiceFactory};
+    use crate::{
+        err, ok,
+        pipeline::{pipeline, pipeline_factory},
+        ready, Ready, Service, ServiceFactory,
+    };
 
     #[derive(Clone)]
     struct Srv1(Rc<Cell<usize>>);

actix-service/src/transform.rs

@@ -21,11 +21,10 @@ where
     ApplyTransform::new(t, factory.into_factory())
 }
 
-/// The `Transform` trait defines the interface of a service factory that wraps inner service
-/// during construction.
+/// Defines the interface of a service factory that wraps inner service during construction.
 ///
-/// Transform(middleware) wraps inner service and runs during inbound and/or outbound processing in
-/// the request/response lifecycle. It may modify request and/or response.
+/// Transformers wrap an inner service and runs during inbound and/or outbound processing in the
+/// service lifecycle. It may modify request and/or response.
 ///
 /// For example, a timeout service wrapper:
 ///