Migrate actix-rt to std::future

actix-rt/Cargo.toml

@@ -19,9 +19,13 @@ path = "src/lib.rs"
 
 [dependencies]
 actix-threadpool = "0.1.1"
-futures = "0.1.25"
+futures = { package = "futures-preview", version  = "0.3.0-alpha.18" }
-tokio-current-thread = "0.1"
+
-tokio-executor = "0.1.5"
+
-tokio-reactor = "0.1.7"
+# TODO: Replace this with dependency on tokio-runtime once it is ready
-tokio-timer = "0.2.8"
+tokio = { version = "0.2.0-alpha.4" }
+tokio-timer = "=0.3.0-alpha.4"
+tokio-executor = "=0.2.0-alpha.4"
+tokio-net = "=0.2.0-alpha.4"
+
 copyless = "0.1.4"

actix-rt/src/arbiter.rs

@@ -3,11 +3,13 @@ use std::cell::{Cell, RefCell};
 use std::collections::HashMap;
 use std::sync::atomic::{AtomicUsize, Ordering};
 use std::{fmt, thread};
+use std::pin::Pin;
+use std::task::Context;
 
-use futures::sync::mpsc::{unbounded, UnboundedReceiver, UnboundedSender};
+use futures::channel::mpsc::{unbounded, UnboundedReceiver, UnboundedSender};
-use futures::sync::oneshot::{channel, Canceled, Sender};
+use futures::channel::oneshot::{channel, Canceled, Sender};
-use futures::{future, Async, Future, IntoFuture, Poll, Stream};
+use futures::{future, Future, Poll, FutureExt, Stream};
-use tokio_current_thread::spawn;
+use tokio::runtime::current_thread::spawn;
 
 use crate::builder::Builder;
 use crate::system::System;
@@ -17,7 +19,7 @@ use copyless::BoxHelper;
 thread_local!(
     static ADDR: RefCell<Option<Arbiter>> = RefCell::new(None);
     static RUNNING: Cell<bool> = Cell::new(false);
-    static Q: RefCell<Vec<Box<dyn Future<Item = (), Error = ()>>>> = RefCell::new(Vec::new());
+    static Q: RefCell<Vec<Box<dyn Future<Output = ()>>>> = RefCell::new(Vec::new());
     static STORAGE: RefCell<HashMap<TypeId, Box<dyn Any>>> = RefCell::new(HashMap::new());
 );
 
@@ -25,7 +27,7 @@ pub(crate) static COUNT: AtomicUsize = AtomicUsize::new(0);
 
 pub(crate) enum ArbiterCommand {
     Stop,
-    Execute(Box<dyn Future<Item = (), Error = ()> + Send>),
+    Execute(Box<dyn Future<Output=()> + Unpin + Send>),
     ExecuteFn(Box<dyn FnExec>),
 }
 
@@ -129,7 +131,9 @@ impl Arbiter {
         Q.with(|cell| {
             let mut v = cell.borrow_mut();
             for fut in v.drain(..) {
-                spawn(fut);
+                // We pin the boxed future, so it can never again be moved.
+                let fut = unsafe { Pin::new_unchecked(fut) };
+                tokio_executor::current_thread::spawn( fut);
             }
         });
     }
@@ -142,14 +146,19 @@ impl Arbiter {
     /// or Arbiter address, it is simply a helper for spawning futures on the current
     /// thread.
     pub fn spawn<F>(future: F)
-    where
+        where
-        F: Future<Item = (), Error = ()> + 'static,
+            F: Future<Output=()> + 'static,
     {
         RUNNING.with(move |cell| {
             if cell.get() {
-                spawn(Box::alloc().init(future));
+                // Spawn the future on running executor
+                spawn(future);
             } else {
-                Q.with(move |cell| cell.borrow_mut().push(Box::alloc().init(future)));
+                // Box the future and push it to the queue, this results in double boxing
+                // because the executor boxes the future again, but works for now
+                Q.with(move |cell| {
+                    cell.borrow_mut().push(Box::alloc().init(future))
+                });
             }
         });
     }
@@ -158,17 +167,17 @@ impl Arbiter {
     /// or Arbiter address, it is simply a helper for executing futures on the current
     /// thread.
     pub fn spawn_fn<F, R>(f: F)
-    where
+        where
-        F: FnOnce() -> R + 'static,
+            F: FnOnce() -> R + 'static,
-        R: IntoFuture<Item = (), Error = ()> + 'static,
+            R: Future<Output=()> + 'static,
     {
-        Arbiter::spawn(future::lazy(f))
+        Arbiter::spawn(future::lazy(|_| f()).flatten())
     }
 
     /// Send a future to the Arbiter's thread, and spawn it.
     pub fn send<F>(&self, future: F)
-    where
+        where
-        F: Future<Item = (), Error = ()> + Send + 'static,
+            F: Future<Output=()> + Send + Unpin + 'static,
     {
         let _ = self
             .0
@@ -178,8 +187,8 @@ impl Arbiter {
     /// Send a function to the Arbiter's thread, and execute it. Any result from the function
     /// is discarded.
     pub fn exec_fn<F>(&self, f: F)
-    where
+        where
-        F: FnOnce() + Send + 'static,
+            F: FnOnce() + Send + 'static,
     {
         let _ = self
             .0
@@ -191,10 +200,10 @@ impl Arbiter {
     /// Send a function to the Arbiter's thread. This function will be executed asynchronously.
     /// A future is created, and when resolved will contain the result of the function sent
     /// to the Arbiters thread.
-    pub fn exec<F, R>(&self, f: F) -> impl Future<Item = R, Error = Canceled>
+    pub fn exec<F, R>(&self, f: F) -> impl Future<Output=Result<R, Canceled>>
-    where
+        where
-        F: FnOnce() -> R + Send + 'static,
+            F: FnOnce() -> R + Send + 'static,
-        R: Send + 'static,
+            R: Send + 'static,
     {
         let (tx, rx) = channel();
         let _ = self
@@ -221,8 +230,8 @@ impl Arbiter {
     ///
     /// Panics is item is not inserted
     pub fn get_item<T: 'static, F, R>(mut f: F) -> R
-    where
+        where
-        F: FnMut(&T) -> R,
+            F: FnMut(&T) -> R,
     {
         STORAGE.with(move |cell| {
             let st = cell.borrow();
@@ -238,8 +247,8 @@ impl Arbiter {
     ///
     /// Panics is item is not inserted
     pub fn get_mut_item<T: 'static, F, R>(mut f: F) -> R
-    where
+        where
-        F: FnMut(&mut T) -> R,
+            F: FnMut(&mut T) -> R,
     {
         STORAGE.with(move |cell| {
             let mut st = cell.borrow_mut();
@@ -269,28 +278,34 @@ impl Drop for ArbiterController {
 }
 
 impl Future for ArbiterController {
-    type Item = ();
+    type Output = ();
-    type Error = ();
 
-    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
         loop {
-            match self.rx.poll() {
+
-                Ok(Async::Ready(None)) | Err(_) => return Ok(Async::Ready(())),
+            match Pin::new(&mut self.rx).poll_next(cx) {
-                Ok(Async::Ready(Some(item))) => match item {
+                Poll::Ready(None) => {
-                    ArbiterCommand::Stop => {
+                    return Poll::Ready(())
-                        if let Some(stop) = self.stop.take() {
+                },
-                            let _ = stop.send(0);
+                Poll::Ready(Some(item)) => {
-                        };
+                    match item {
-                        return Ok(Async::Ready(()));
+                        ArbiterCommand::Stop => {
-                    }
+                            if let Some(stop) = self.stop.take() {
-                    ArbiterCommand::Execute(fut) => {
+                                let _ = stop.send(0);
-                        spawn(fut);
+                            };
-                    }
+                            return Poll::Ready(());
-                    ArbiterCommand::ExecuteFn(f) => {
+                        }
-                        f.call_box();
+                        ArbiterCommand::Execute(fut) => {
-                    }
+                            spawn(fut);
+                        }
+                        ArbiterCommand::ExecuteFn(f) => {
+                            f.call_box();
+                        }
+                    }
+                }
+                Poll::Pending =>  {
+                    return Poll::Pending
                 },
-                Ok(Async::NotReady) => return Ok(Async::NotReady),
             }
         }
     }
@@ -321,14 +336,13 @@ impl SystemArbiter {
 }
 
 impl Future for SystemArbiter {
-    type Item = ();
+    type Output = ();
-    type Error = ();
 
-    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
         loop {
-            match self.commands.poll() {
+            match Pin::new(&mut self.commands).poll_next(cx) {
-                Ok(Async::Ready(None)) | Err(_) => return Ok(Async::Ready(())),
+                Poll::Ready(None) => return Poll::Ready(()),
-                Ok(Async::Ready(Some(cmd))) => match cmd {
+                Poll::Ready(Some(cmd)) => match cmd {
                     SystemCommand::Exit(code) => {
                         // stop arbiters
                         for arb in self.arbiters.values() {
@@ -346,7 +360,7 @@ impl Future for SystemArbiter {
                         self.arbiters.remove(&name);
                     }
                 },
-                Ok(Async::NotReady) => return Ok(Async::NotReady),
+                Poll::Pending => return Poll::Pending,
             }
         }
     }
@@ -357,8 +371,8 @@ pub trait FnExec: Send + 'static {
 }
 
 impl<F> FnExec for F
-where
+    where
-    F: FnOnce() + Send + 'static,
+        F: FnOnce() + Send + 'static,
 {
     #[allow(clippy::boxed_local)]
     fn call_box(self: Box<Self>) {

actix-rt/src/builder.rs

@@ -1,19 +1,19 @@
 use std::borrow::Cow;
 use std::io;
 
-use futures::future;
+use futures::{future, FutureExt};
 use futures::future::{lazy, Future};
-use futures::sync::mpsc::unbounded;
+use futures::channel::mpsc::unbounded;
-use futures::sync::oneshot::{channel, Receiver};
+use futures::channel::oneshot::{channel, Receiver};
 
-use tokio_current_thread::{CurrentThread, Handle};
+use tokio::runtime::current_thread::Handle;
-use tokio_reactor::Reactor;
+use tokio_timer::{timer::Timer, clock::Clock};
-use tokio_timer::clock::Clock;
+use tokio_net::driver::Reactor;
-use tokio_timer::timer::Timer;
 
 use crate::arbiter::{Arbiter, SystemArbiter};
 use crate::runtime::Runtime;
 use crate::system::System;
+use tokio_executor::current_thread::CurrentThread;
 
 /// Builder struct for a actix runtime.
 ///
@@ -118,7 +118,7 @@ impl Builder {
         rt.spawn(arb);
 
         // init system arbiter and run configuration method
-        let _ = rt.block_on(lazy(move || {
+        let _ = rt.block_on(lazy(move |_| {
             f();
             Ok::<_, ()>(())
         }));
@@ -159,30 +159,30 @@ pub(crate) struct AsyncSystemRunner {
 impl AsyncSystemRunner {
     /// This function will start event loop and returns a future that
     /// resolves once the `System::stop()` function is called.
-    pub(crate) fn run_nonblocking(self) -> impl Future<Item = (), Error = io::Error> + Send {
+    pub(crate) fn run_nonblocking(self) -> impl Future<Output = Result<(),io::Error>> + Send {
         let AsyncSystemRunner { stop, .. } = self;
 
         // run loop
-        future::lazy(|| {
+        future::lazy(|_| {
             Arbiter::run_system();
-            stop.then(|res| match res {
+            async {
-                Ok(code) => {
+                let res = match stop.await {
-                    if code != 0 {
+                    Ok(code) => {
-                        Err(io::Error::new(
+                        if code != 0 {
-                            io::ErrorKind::Other,
+                            Err(io::Error::new(
-                            format!("Non-zero exit code: {}", code),
+                                io::ErrorKind::Other,
-                        ))
+                                format!("Non-zero exit code: {}", code),
-                    } else {
+                            ))
-                        Ok(())
+                        } else {
+                            Ok(())
+                        }
                     }
-                }
+                    Err(e) => Err(io::Error::new(io::ErrorKind::Other, e)),
-                Err(e) => Err(io::Error::new(io::ErrorKind::Other, e)),
+                };
-            })
-            .then(|result| {
                 Arbiter::stop_system();
-                result
+                return res;
-            })
+            }
-        })
+        }).flatten()
     }
 }
 
@@ -202,10 +202,10 @@ impl SystemRunner {
         let SystemRunner { mut rt, stop, .. } = self;
 
         // run loop
-        let _ = rt.block_on(lazy(move || {
+        let _ = rt.block_on(async {
             Arbiter::run_system();
             Ok::<_, ()>(())
-        }));
+        });
         let result = match rt.block_on(stop) {
             Ok(code) => {
                 if code != 0 {
@@ -224,19 +224,19 @@ impl SystemRunner {
     }
 
     /// Execute a future and wait for result.
-    pub fn block_on<F, I, E>(&mut self, fut: F) -> Result<I, E>
+    pub fn block_on<F, O>(&mut self, fut: F) -> O
     where
-        F: Future<Item = I, Error = E>,
+        F: Future<Output = O>,
     {
-        let _ = self.rt.block_on(lazy(move || {
+        let _ = self.rt.block_on(async {
             Arbiter::run_system();
-            Ok::<_, ()>(())
+        });
-        }));
+
         let res = self.rt.block_on(fut);
-        let _ = self.rt.block_on(lazy(move || {
+        let _ = self.rt.block_on(async {
             Arbiter::stop_system();
-            Ok::<_, ()>(())
+        });
-        }));
+
         res
     }
 }

actix-rt/src/lib.rs

@@ -20,7 +20,7 @@ pub use actix_threadpool as blocking;
 /// This function panics if actix system is not running.
 pub fn spawn<F>(f: F)
 where
-    F: futures::Future<Item = (), Error = ()> + 'static,
+    F: futures::Future<Output = ()>  + 'static,
 {
     if !System::is_set() {
         panic!("System is not running");

actix-rt/src/runtime.rs

@@ -2,11 +2,9 @@ use std::error::Error;
 use std::{fmt, io};
 
 use futures::Future;
-use tokio_current_thread::{self as current_thread, CurrentThread};
+use tokio_executor::current_thread::{self, CurrentThread};
-use tokio_executor;
+use tokio_timer::{timer::{self, Timer}, clock::Clock};
-use tokio_reactor::{self, Reactor};
+use tokio_net::driver::{Reactor, Handle as ReactorHandle};
-use tokio_timer::clock::{self, Clock};
-use tokio_timer::timer::{self, Timer};
 
 use crate::builder::Builder;
 
@@ -18,7 +16,7 @@ use crate::builder::Builder;
 /// [mod]: index.html
 #[derive(Debug)]
 pub struct Runtime {
-    reactor_handle: tokio_reactor::Handle,
+    reactor_handle: ReactorHandle,
     timer_handle: timer::Handle,
     clock: Clock,
     executor: CurrentThread<Timer<Reactor>>,
@@ -53,7 +51,7 @@ impl Runtime {
     }
 
     pub(super) fn new2(
-        reactor_handle: tokio_reactor::Handle,
+        reactor_handle: ReactorHandle,
         timer_handle: timer::Handle,
         clock: Clock,
         executor: CurrentThread<Timer<Reactor>>,
@@ -97,7 +95,7 @@ impl Runtime {
     /// is currently at capacity and is unable to spawn a new future.
     pub fn spawn<F>(&mut self, future: F) -> &mut Self
     where
-        F: Future<Item = (), Error = ()> + 'static,
+        F: Future<Output = (),> + 'static,
     {
         self.executor.spawn(future);
         self
@@ -119,14 +117,14 @@ impl Runtime {
     ///
     /// The caller is responsible for ensuring that other spawned futures
     /// complete execution by calling `block_on` or `run`.
-    pub fn block_on<F>(&mut self, f: F) -> Result<F::Item, F::Error>
+    pub fn block_on<F>(&mut self, f: F) -> F::Output
     where
         F: Future,
     {
         self.enter(|executor| {
             // Run the provided future
             let ret = executor.block_on(f);
-            ret.map_err(|e| e.into_inner().expect("unexpected execution error"))
+            ret
         })
     }
 
@@ -139,7 +137,7 @@ impl Runtime {
 
     fn enter<F, R>(&mut self, f: F) -> R
     where
-        F: FnOnce(&mut current_thread::Entered<Timer<Reactor>>) -> R,
+        F: FnOnce(&mut CurrentThread<Timer<Reactor>>) -> R,
     {
         let Runtime {
             ref reactor_handle,
@@ -149,25 +147,14 @@ impl Runtime {
             ..
         } = *self;
 
-        // Binds an executor to this thread
+        // WARN: We do not enter the executor here, since in tokio 0.2 the executor is entered
-        let mut enter = tokio_executor::enter().expect("Multiple executors at once");
+        // automatically inside its `block_on` and `run` methods
 
-        // This will set the default handle and timer to use inside the closure
+        tokio_executor::with_default(&mut current_thread::TaskExecutor::current(),|| {
-        // and run the future.
+            tokio_timer::clock::with_default(clock, || {
-        tokio_reactor::with_default(&reactor_handle, &mut enter, |enter| {
+                let _reactor_guard = tokio_net::driver::set_default(reactor_handle);
-            clock::with_default(clock, enter, |enter| {
+                let _timer_guard = tokio_timer::set_default(timer_handle);
-                timer::with_default(&timer_handle, enter, |enter| {
+                f(executor)
-                    // The TaskExecutor is a fake executor that looks into the
-                    // current single-threaded executor when used. This is a trick,
-                    // because we need two mutable references to the executor (one
-                    // to run the provided future, another to install as the default
-                    // one). We use the fake one here as the default one.
-                    let mut default_executor = current_thread::TaskExecutor::current();
-                    tokio_executor::with_default(&mut default_executor, enter, |enter| {
-                        let mut executor = executor.enter(enter);
-                        f(&mut executor)
-                    })
-                })
             })
         })
     }

actix-rt/src/system.rs

@@ -2,9 +2,9 @@ use std::cell::RefCell;
 use std::io;
 use std::sync::atomic::{AtomicUsize, Ordering};
 
-use futures::sync::mpsc::UnboundedSender;
+use futures::channel::mpsc::UnboundedSender;
 use futures::Future;
-use tokio_current_thread::Handle;
+use tokio::runtime::current_thread::Handle;
 
 use crate::arbiter::{Arbiter, SystemCommand};
 use crate::builder::{Builder, SystemRunner};
@@ -64,7 +64,7 @@ impl System {
     pub fn run_in_executor<T: Into<String>>(
         name: T,
         executor: Handle,
-    ) -> impl Future<Item = (), Error = io::Error> + Send {
+    ) -> impl Future<Output = Result<(), io::Error>> + Send {
         Self::builder()
             .name(name)
             .build_async(executor)