Conditially require serialize

.travis.yml

@@ -15,7 +15,7 @@ before_cache:
   - ./ci/clear_cache.sh
 
 rust:
-  - 1.40.0 # min supported
+  - 1.42.0 # min supported
   - stable
   - beta
 

README.md

@@ -11,7 +11,7 @@
     <a href="https://crates.io/crates/yew"><img alt="Crate Info" src="https://img.shields.io/crates/v/yew.svg"/></a>
     <a href="https://docs.rs/yew/"><img alt="API Docs" src="https://img.shields.io/badge/docs.rs-yew-green"/></a>
     <a href="https://discord.gg/VQck8X4"><img alt="Discord Chat" src="https://img.shields.io/discord/701068342760570933"/></a>
-    <a href="https://blog.rust-lang.org/2019/12/19/Rust-1.40.0.html"><img alt="Rustc Version 1.40+" src="https://img.shields.io/badge/rustc-1.40+-lightgray.svg"/></a>
+    <a href="https://blog.rust-lang.org/2020/03/12/Rust-1.42.html"><img alt="Rustc Version 1.42+" src="https://img.shields.io/badge/rustc-1.42%2B-lightgrey.svg"/></a>
     <a href="https://github.com/jetli/awesome-yew"><img alt="Yew Awesome" src="https://raw.githubusercontent.com/sindresorhus/awesome/master/media/badge.svg"/></a>
   </p>
 

examples/multi_thread/src/context.rs

@@ -25,7 +25,7 @@ pub struct Worker {
 }
 
 impl Agent for Worker {
-    type Reach = Context;
+    type Reach = Context<Self>;
     type Message = Msg;
     type Input = Request;
     type Output = Response;

examples/multi_thread/src/job.rs

@@ -25,7 +25,7 @@ pub struct Worker {
 }
 
 impl Agent for Worker {
-    type Reach = Job;
+    type Reach = Job<Self>;
     type Message = Msg;
     type Input = Request;
     type Output = Response;

examples/multi_thread/src/native_worker.rs

@@ -25,7 +25,7 @@ pub struct Worker {
 }
 
 impl Agent for Worker {
-    type Reach = Public;
+    type Reach = Public<Self>;
     type Message = Msg;
     type Input = Request;
     type Output = Response;

examples/pub_sub/src/event_bus.rs

@@ -13,7 +13,7 @@ pub struct EventBus {
 }
 
 impl Agent for EventBus {
-    type Reach = Context;
+    type Reach = Context<Self>;
     type Message = ();
     type Input = Request;
     type Output = String;

yew-router/src/agent/mod.rs

@@ -87,7 +87,7 @@ where
     type Input = RouteRequest<STATE>;
     type Message = Msg<STATE>;
     type Output = Route<STATE>;
-    type Reach = Context;
+    type Reach = Context<Self>;
 
     fn create(link: AgentLink<RouteAgent<STATE>>) -> Self {
         let callback = link.callback(Msg::BrowserNavigationRouteChanged);

yew-stdweb/examples/multi_thread/src/context.rs

@@ -25,7 +25,7 @@ pub struct Worker {
 }
 
 impl Agent for Worker {
-    type Reach = Context;
+    type Reach = Context<Self>;
     type Message = Msg;
     type Input = Request;
     type Output = Response;

yew-stdweb/examples/multi_thread/src/job.rs

@@ -25,7 +25,7 @@ pub struct Worker {
 }
 
 impl Agent for Worker {
-    type Reach = Job;
+    type Reach = Job<Self>;
     type Message = Msg;
     type Input = Request;
     type Output = Response;

yew-stdweb/examples/multi_thread/src/native_worker.rs

@@ -25,7 +25,7 @@ pub struct Worker {
 }
 
 impl Agent for Worker {
-    type Reach = Public;
+    type Reach = Public<Self>;
     type Message = Msg;
     type Input = Request;
     type Output = Response;

yew/src/agent/local/context.rs

@@ -4,6 +4,7 @@ use crate::scheduler::Shared;
 use anymap::{self, AnyMap};
 use slab::Slab;
 use std::cell::RefCell;
+use std::marker::PhantomData;
 use std::rc::Rc;
 
 thread_local! {
@@ -12,10 +13,17 @@ thread_local! {
 
 /// Create a single instance in the current thread.
 #[allow(missing_debug_implementations)]
-pub struct Context;
+pub struct Context<AGN> {
+    _agent: PhantomData<AGN>,
+}
+
+impl<AGN> Discoverer for Context<AGN>
+where
+    AGN: Agent,
+{
+    type Agent = AGN;
 
-impl Discoverer for Context {
-    fn spawn_or_join<AGN: Agent>(callback: Option<Callback<AGN::Output>>) -> Box<dyn Bridge<AGN>> {
+    fn spawn_or_join(callback: Option<Callback<AGN::Output>>) -> Box<dyn Bridge<AGN>> {
         let mut scope_to_init = None;
         let bridge = LOCAL_AGENTS_POOL.with(|pool| {
             let mut pool = pool.borrow_mut();
@@ -53,7 +61,7 @@ impl<AGN: Agent> Responder<AGN> for SlabResponder<AGN> {
     }
 }
 
-impl Dispatchable for Context {}
+impl<AGN: Agent> Dispatchable for Context<AGN> {}
 
 struct ContextBridge<AGN: Agent> {
     scope: AgentScope<AGN>,

yew/src/agent/local/job.rs

@@ -1,14 +1,22 @@
 use super::*;
 use crate::callback::Callback;
+use std::marker::PhantomData;
 
 const SINGLETON_ID: HandlerId = HandlerId(0, true);
 
 /// Create an instance in the current thread.
 #[allow(missing_debug_implementations)]
-pub struct Job;
+pub struct Job<AGN> {
+    _agent: PhantomData<AGN>,
+}
+
+impl<AGN> Discoverer for Job<AGN>
+where
+    AGN: Agent,
+{
+    type Agent = AGN;
 
-impl Discoverer for Job {
-    fn spawn_or_join<AGN: Agent>(callback: Option<Callback<AGN::Output>>) -> Box<dyn Bridge<AGN>> {
+    fn spawn_or_join(callback: Option<Callback<AGN::Output>>) -> Box<dyn Bridge<AGN>> {
         let callback = callback.expect("Callback required for Job");
         let scope = AgentScope::<AGN>::new();
         let responder = CallbackResponder { callback };

yew/src/agent/mod.rs

@@ -1,4 +1,4 @@
-//! This module contains types to support multi-threading in Yew.
+//! This module contains types to support multi-threading and state management.
 
 mod link;
 mod local;
@@ -20,13 +20,13 @@ use std::ops::{Deref, DerefMut};
 /// Declares the behavior of the agent.
 pub trait Agent: Sized + 'static {
     /// Reach capability of the agent.
-    type Reach: Discoverer;
+    type Reach: Discoverer<Agent = Self>;
     /// Type of an input message.
     type Message;
     /// Incoming message type.
-    type Input: Serialize + for<'de> Deserialize<'de>;
+    type Input;
     /// Outgoing message type.
-    type Output: Serialize + for<'de> Deserialize<'de>;
+    type Output;
 
     /// Creates an instance of an agent.
     fn create(link: AgentLink<Self>) -> Self;
@@ -76,6 +76,23 @@ impl HandlerId {
     }
 }
 
+/// Determine a visibility of an agent.
+#[doc(hidden)]
+pub trait Discoverer {
+    type Agent: Agent;
+
+    /// Spawns an agent and returns `Bridge` implementation.
+    fn spawn_or_join(
+        _callback: Option<Callback<<Self::Agent as Agent>::Output>>,
+    ) -> Box<dyn Bridge<Self::Agent>>;
+}
+
+/// Bridge to a specific kind of worker.
+pub trait Bridge<AGN: Agent> {
+    /// Send a message to an agent.
+    fn send(&mut self, msg: AGN::Input);
+}
+
 /// This trait allows registering or getting the address of a worker.
 pub trait Bridged: Agent + Sized + 'static {
     /// Creates a messaging bridge between a worker and the component.
@@ -85,21 +102,9 @@ pub trait Bridged: Agent + Sized + 'static {
 impl<T> Bridged for T
 where
     T: Agent,
+    <T as Agent>::Reach: Discoverer<Agent = T>,
 {
     fn bridge(callback: Callback<Self::Output>) -> Box<dyn Bridge<Self>> {
         Self::Reach::spawn_or_join(Some(callback))
     }
 }
-
-/// Determine a visibility of an agent.
-#[doc(hidden)]
-pub trait Discoverer {
-    /// Spawns an agent and returns `Bridge` implementation.
-    fn spawn_or_join<AGN: Agent>(_callback: Option<Callback<AGN::Output>>) -> Box<dyn Bridge<AGN>>;
-}
-
-/// Bridge to a specific kind of worker.
-pub trait Bridge<AGN: Agent> {
-    /// Send a message to an agent.
-    fn send(&mut self, msg: AGN::Input);
-}

yew/src/agent/pool.rs

@@ -77,9 +77,10 @@ pub trait Dispatchable {}
 impl<T> Dispatched for T
 where
     T: Agent,
+    <T as Agent>::Reach: Discoverer<Agent = T>,
     <T as Agent>::Reach: Dispatchable,
 {
     fn dispatcher() -> Dispatcher<T> {
-        Dispatcher(Self::Reach::spawn_or_join::<T>(None))
+        Dispatcher(Self::Reach::spawn_or_join(None))
     }
 }

yew/src/agent/worker/mod.rs

@@ -68,11 +68,15 @@ enum FromWorker<T> {
     ProcessOutput(HandlerId, T),
 }
 
-fn send_to_remote<AGN: Agent>(
+fn send_to_remote<AGN>(
     #[cfg(feature = "std_web")] worker: &Value,
     #[cfg(feature = "web_sys")] worker: &Worker,
     msg: ToWorker<AGN::Input>,
-) {
+) where
+    AGN: Agent,
+    <AGN as Agent>::Input: Serialize + for<'de> Deserialize<'de>,
+    <AGN as Agent>::Output: Serialize + for<'de> Deserialize<'de>,
+{
     let msg = msg.pack();
     cfg_match! {
         feature = "std_web" => js! {

yew/src/agent/worker/private.rs

@@ -18,10 +18,19 @@ const SINGLETON_ID: HandlerId = HandlerId(0, true);
 
 /// Create a new instance for every bridge.
 #[allow(missing_debug_implementations)]
-pub struct Private;
+pub struct Private<AGN> {
+    _agent: PhantomData<AGN>,
+}
+
+impl<AGN> Discoverer for Private<AGN>
+where
+    AGN: Agent,
+    <AGN as Agent>::Input: Serialize + for<'de> Deserialize<'de>,
+    <AGN as Agent>::Output: Serialize + for<'de> Deserialize<'de>,
+{
+    type Agent = AGN;
 
-impl Discoverer for Private {
-    fn spawn_or_join<AGN: Agent>(callback: Option<Callback<AGN::Output>>) -> Box<dyn Bridge<AGN>> {
+    fn spawn_or_join(callback: Option<Callback<AGN::Output>>) -> Box<dyn Bridge<AGN>> {
         let callback = callback.expect("Callback required for Private agents");
         let handler = move |data: Vec<u8>,
                             #[cfg(feature = "std_web")] worker: Value,
@@ -65,21 +74,36 @@ impl Discoverer for Private {
 }
 
 /// A connection manager for components interaction with workers.
-pub struct PrivateBridge<T: Agent> {
+pub struct PrivateBridge<AGN>
+where
+    AGN: Agent,
+    <AGN as Agent>::Input: Serialize + for<'de> Deserialize<'de>,
+    <AGN as Agent>::Output: Serialize + for<'de> Deserialize<'de>,
+{
     #[cfg(feature = "std_web")]
     worker: Value,
     #[cfg(feature = "web_sys")]
     worker: Worker,
-    _agent: PhantomData<T>,
+    _agent: PhantomData<AGN>,
 }
 
-impl<AGN: Agent> fmt::Debug for PrivateBridge<AGN> {
+impl<AGN> fmt::Debug for PrivateBridge<AGN>
+where
+    AGN: Agent,
+    <AGN as Agent>::Input: Serialize + for<'de> Deserialize<'de>,
+    <AGN as Agent>::Output: Serialize + for<'de> Deserialize<'de>,
+{
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.write_str("PrivateBridge<_>")
     }
 }
 
-impl<AGN: Agent> Bridge<AGN> for PrivateBridge<AGN> {
+impl<AGN> Bridge<AGN> for PrivateBridge<AGN>
+where
+    AGN: Agent,
+    <AGN as Agent>::Input: Serialize + for<'de> Deserialize<'de>,
+    <AGN as Agent>::Output: Serialize + for<'de> Deserialize<'de>,
+{
     fn send(&mut self, msg: AGN::Input) {
         // TODO(#937): Important! Implement.
         // Use a queue to collect a messages if an instance is not ready
@@ -99,7 +123,12 @@ impl<AGN: Agent> Bridge<AGN> for PrivateBridge<AGN> {
     }
 }
 
-impl<AGN: Agent> Drop for PrivateBridge<AGN> {
+impl<AGN> Drop for PrivateBridge<AGN>
+where
+    AGN: Agent,
+    <AGN as Agent>::Input: Serialize + for<'de> Deserialize<'de>,
+    <AGN as Agent>::Output: Serialize + for<'de> Deserialize<'de>,
+{
     fn drop(&mut self) {
         let disconnected = ToWorker::Disconnected(SINGLETON_ID);
         send_to_remote::<AGN>(&self.worker, disconnected);