Migrate actix-net to std::future (#64)

* Migrate actix-codec, actix-rt, and actix-threadpool to std::future

* update to latest tokio alpha and futures-rs

* Migrate actix-service to std::future,

This is a squash of ~8 commits, since it included a lot of experimentation. To see the commits,
look into the semtexzv/std-future-service-tmp branch.

* update futures-rs and tokio

* Migrate actix-threadpool to std::future (#59)

* Migrate actix-threadpool to std::future

* Cosmetic refactor

- turn log::error! into log::warn! as it doesn't throw any error
- add Clone and Copy impls for Cancelled making it cheap to operate with
- apply rustfmt

* Bump up crate version to 0.2.0 and pre-fill its changelog

* Disable patching 'actix-threadpool' crate in global workspace as unnecessary

* Revert patching and fix 'actix-rt'

* Migrate actix-rt to std::future (#47)

* remove Pin from Service::poll_ready(); simplify combinators api; make code compile

* disable tests

* update travis config

* refactor naming

* drop IntoFuture trait

* Migrate actix-server to std::future (#50)

Still not finished, this is more WIP, this is an aggregation of several commits, which
can be found in semtexzv/std-future-server-tmp branch

* update actix-server

* rename Factor to ServiceFactory

* start server worker in start mehtod

* update actix-utils

* remove IntoTransform trait

* Migrate actix-server::ssl::nativetls to std futures (#61)

* Refactor 'nativetls' module

* Migrate 'actix-server-config' to std futures

- remove "uds" feature
- disable features by default

* Switch NativeTlsAcceptor to use 'tokio-tls' crate

* Bikeshed features names and remove unnecessary dependencies for 'actix-server-config' crate

* update openssl impl

* migrate actix-connect to std::future

* migrate actix-ioframe to std::future

* update version to alpha.1

* fix boxed service

* migrate server rustls support

* migratte openssl and rustls connecttors

* store the thread's handle with arbiter (#62)

* update ssl connect tests

* restore service tests

* update readme

actix-threadpool/CHANGES.md

@@ -1,5 +1,11 @@
 # Changes
 
+## [0.2.0] - 2019-??-??
+
+### Changed
+
+* Migrate to `std::future`
+
 ## [0.1.2] - 2019-08-05
 
 ### Changed

actix-threadpool/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "actix-threadpool"
-version = "0.1.2"
+version = "0.2.0"
 authors = ["Nikolay Kim <fafhrd91@gmail.com>"]
 description = "Actix thread pool for sync code"
 keywords = ["actix", "network", "framework", "async", "futures"]
@@ -19,7 +19,7 @@ path = "src/lib.rs"
 
 [dependencies]
 derive_more = "0.15"
-futures = "0.1.25"
+futures = "0.3.1"
 parking_lot = "0.9"
 lazy_static = "1.2"
 log = "0.4"

actix-threadpool/src/lib.rs

@@ -1,33 +1,34 @@
 //! Thread pool for blocking operations
 
-use std::fmt;
+use std::{
+    future::Future,
+    pin::Pin,
+    task::{Context, Poll},
+};
 
 use derive_more::Display;
-use futures::sync::oneshot;
-use futures::{Async, Future, Poll};
+use futures::channel::oneshot;
 use parking_lot::Mutex;
 use threadpool::ThreadPool;
 
-/// Env variable for default cpu pool size
+/// Env variable for default cpu pool size.
 const ENV_CPU_POOL_VAR: &str = "ACTIX_THREADPOOL";
 
 lazy_static::lazy_static! {
     pub(crate) static ref DEFAULT_POOL: Mutex<ThreadPool> = {
-        let default = match std::env::var(ENV_CPU_POOL_VAR) {
-            Ok(val) => {
-                if let Ok(val) = val.parse() {
-                    val
-                } else {
-                    log::error!("Can not parse ACTIX_THREADPOOL value");
-                    num_cpus::get() * 5
-                }
-            }
-            Err(_) => num_cpus::get() * 5,
-        };
+        let num = std::env::var(ENV_CPU_POOL_VAR)
+            .map_err(|_| ())
+            .and_then(|val| {
+                val.parse().map_err(|_| log::warn!(
+                    "Can not parse {} value, using default",
+                    ENV_CPU_POOL_VAR,
+                ))
+            })
+            .unwrap_or_else(|_| num_cpus::get() * 5);
         Mutex::new(
             threadpool::Builder::new()
                 .thread_name("actix-web".to_owned())
-                .num_threads(default)
+                .num_threads(num)
                 .build(),
         )
     };
@@ -39,22 +40,17 @@ thread_local! {
     };
 }
 
-/// Blocking operation execution error
-#[derive(Debug, Display)]
-pub enum BlockingError<E: fmt::Debug> {
-    #[display(fmt = "{:?}", _0)]
-    Error(E),
-    #[display(fmt = "Thread pool is gone")]
-    Canceled,
-}
+/// Error of blocking operation execution being cancelled.
+#[derive(Clone, Copy, Debug, Display)]
+#[display(fmt = "Thread pool is gone")]
+pub struct Cancelled;
 
 /// Execute blocking function on a thread pool, returns future that resolves
 /// to result of the function execution.
-pub fn run<F, I, E>(f: F) -> CpuFuture<I, E>
+pub fn run<F, I>(f: F) -> CpuFuture<I>
 where
-    F: FnOnce() -> Result<I, E> + Send + 'static,
+    F: FnOnce() -> I + Send + 'static,
     I: Send + 'static,
-    E: Send + fmt::Debug + 'static,
 {
     let (tx, rx) = oneshot::channel();
     POOL.with(|pool| {
@@ -70,19 +66,16 @@ where
 
 /// Blocking operation completion future. It resolves with results
 /// of blocking function execution.
-pub struct CpuFuture<I, E> {
-    rx: oneshot::Receiver<Result<I, E>>,
+pub struct CpuFuture<I> {
+    rx: oneshot::Receiver<I>,
 }
 
-impl<I, E: fmt::Debug> Future for CpuFuture<I, E> {
-    type Item = I;
-    type Error = BlockingError<E>;
+impl<I> Future for CpuFuture<I> {
+    type Output = Result<I, Cancelled>;
 
-    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
-        let res = futures::try_ready!(self.rx.poll().map_err(|_| BlockingError::Canceled));
-        match res {
-            Ok(val) => Ok(Async::Ready(val)),
-            Err(err) => Err(BlockingError::Error(err)),
-        }
+    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+        let rx = Pin::new(&mut Pin::get_mut(self).rx);
+        let res = futures::ready!(rx.poll(cx));
+        Poll::Ready(res.map_err(|_| Cancelled))
     }
 }