Merge pull request #418 from cunarist/allow-choosing-async-runtime

Allow choosing async runtime

.github/workflows/quality_control.yaml

@@ -68,7 +68,9 @@ jobs:
       # That's why we are checking only the library crate.
       - name: Check for errors with all features enabled
         working-directory: rust_crate/
-        run: cargo clippy --all-features
+        run: |
+          cargo clippy --all-features
+          cargo clippy --all-features --target wasm32-unknown-unknown
 
       - name: Analyze code
         run: |

documentation/docs/configuration.md

@@ -27,6 +27,5 @@ Customizing the behavior of the Rinf crate is possible through its crate feature
 rinf = { version = "0.0.0", features = ["feature-name"] }
 ```
 
-- `rt-multi-thread`: Starts a worker thread for each CPU core available on the system within the `tokio` runtime by enabling its `rt-multi-thread` feature. By default, the `tokio` runtime uses only one thread. Enabling this feature allows the `tokio` runtime to utilize all the cores on your computer. This feature does not affect applications on the web platform.
 - `show-backtrace`: Prints the full backtrace in the CLI when a panic occurs in debug mode. In general, backtrace is not very helpful when debugging async apps, so consider using [`tracing`](https://crates.io/crates/tracing) for logging purposes. Note that this feature does not affect debugging on the web platform.
 - `bevy`: Implements the `Event` trait from `bevy_ecs` for `DartSignal`, allowing Bevy's entity component system to listen for events from Dart.

flutter_ffi_plugin/example/native/hub/Cargo.toml

@@ -14,7 +14,12 @@ crate-type = ["lib", "cdylib", "staticlib"]
 [dependencies]
 rinf = "6.15.0"
 prost = "0.13.0"
-tokio = { version = "1", features = ["rt", "sync", "time"] }
-tokio_with_wasm = { version = "0.6.3", features = ["rt", "sync", "time"] }
+tokio = { version = "1", features = ["rt", "sync", "time", "macros"] }
+tokio_with_wasm = { version = "0.7.1", features = [
+    "rt",
+    "sync",
+    "time",
+    "macros",
+] }
 wasm-bindgen = "0.2.93"
 sample_crate = { path = "../sample_crate" }

flutter_ffi_plugin/example/native/hub/src/lib.rs

@@ -6,6 +6,7 @@ mod messages;
 mod sample_functions;
 
 // use tokio;
+use common::*;
 use tokio_with_wasm::alias as tokio;
 
 rinf::write_interface!();
@@ -15,8 +16,17 @@ rinf::write_interface!();
 // such as `tokio::fs::File::open`.
 // If you really need to use blocking code,
 // use `tokio::task::spawn_blocking`.
-async fn main() {
+#[tokio::main(flavor = "current_thread")]
+async fn main() -> Result<()> {
+    // Spawn the concurrent tasks.
     tokio::spawn(sample_functions::tell_numbers());
     tokio::spawn(sample_functions::stream_fractal());
     tokio::spawn(sample_functions::run_debug_tests());
+
+    // Get the shutdown receiver from Rinf.
+    // This receiver will await a signal from Dart shutdown.
+    let shutdown_receiver = rinf::get_shutdown_receiver()?;
+    shutdown_receiver.await;
+
+    Ok(())
 }

flutter_ffi_plugin/example/native/hub/src/sample_functions.rs

@@ -5,22 +5,19 @@ use crate::messages;
 use crate::tokio;
 use rinf::debug_print;
 use std::time::Duration;
-use tokio::sync::Mutex;
 
 // Using the `cfg` macro enables conditional statement.
 #[cfg(debug_assertions)]
-const IS_DEBUG_MODE: bool = true;
+static IS_DEBUG_MODE: bool = true;
 #[cfg(not(debug_assertions))]
-const IS_DEBUG_MODE: bool = false;
-
-// This is one of the ways to keep a global mutable state in Rust.
-// You can also use `tokio::sync::RwLock` or `std::lazy::LazyLock`.
-static VECTOR: Mutex<Vec<bool>> = Mutex::const_new(Vec::new());
+static IS_DEBUG_MODE: bool = false;
 
 // Business logic for the counter widget.
 pub async fn tell_numbers() -> Result<()> {
     use messages::counter_number::*;
 
+    let mut vector = Vec::new();
+
     // Stream getter is generated from a marked Protobuf message.
     let receiver = SampleNumberInput::get_dart_signal_receiver()?;
     while let Some(dart_signal) = receiver.recv().await {
@@ -30,8 +27,7 @@ pub async fn tell_numbers() -> Result<()> {
         let letter = number_input.letter;
         debug_print!("{letter}");
 
-        // Use the global state and perform a simple calculation.
-        let mut vector = VECTOR.lock().await;
+        // Perform a simple calculation.
         vector.push(true);
         let current_number = (vector.len() as i32) * 7;
 

flutter_ffi_plugin/template/native/hub/Cargo.toml

@@ -14,8 +14,8 @@ crate-type = ["lib", "cdylib", "staticlib"]
 [dependencies]
 rinf = "6.15.0"
 prost = "0.12.6"
-tokio = { version = "1", features = ["rt"] }
+tokio = { version = "1", features = ["rt", "macros"] }
 
 # Uncomment below to target the web.
-# tokio_with_wasm = { version = "0.6.0", features = ["rt"] }
+# tokio_with_wasm = { version = "0.6.0", features = ["rt", "macros"] }
 # wasm-bindgen = "0.2.92"

flutter_ffi_plugin/template/native/hub/src/lib.rs

@@ -15,19 +15,31 @@ rinf::write_interface!();
 // such as `tokio::fs::File::open`.
 // If you really need to use blocking code,
 // use `tokio::task::spawn_blocking`.
-async fn main() {
+#[tokio::main(flavor = "current_thread")]
+async fn main() -> Result<()> {
+    // Spawn the concurrent tasks.
     tokio::spawn(communicate());
+
+    // Get the shutdown receiver from Rinf.
+    // This receiver will await a signal from Dart shutdown.
+    let shutdown_receiver = rinf::get_shutdown_receiver()?;
+    shutdown_receiver.await;
+
+    Ok(())
 }
 
 async fn communicate() -> Result<()> {
     use messages::basic::*;
+
     // Send signals to Dart like below.
     SmallNumber { number: 7 }.send_signal_to_dart();
+
     // Get receivers that listen to Dart signals like below.
     let receiver = SmallText::get_dart_signal_receiver()?;
     while let Some(dart_signal) = receiver.recv().await {
         let message: SmallText = dart_signal.message;
         rinf::debug_print!("{message:?}");
     }
+
     Ok(())
 }

rust_crate/Cargo.toml

@@ -9,7 +9,6 @@ documentation = "https://rinf.cunarist.com"
 rust-version = "1.70"
 
 [features]
-rt-multi-thread = ["tokio/rt-multi-thread"]
 show-backtrace = ["backtrace"]
 bevy = ["bevy_ecs"]
 
@@ -23,7 +22,6 @@ protoc-prebuilt = "0.3.0"
 home = "0.5.9"
 which = "6.0.0"
 allo-isolate = "0.1.25"
-tokio = { version = "1", features = ["rt"] }
 
 [target.'cfg(target_family = "wasm")'.dependencies]
 js-sys = "0.3.69"

rust_crate/src/error.rs

@@ -5,7 +5,8 @@ use std::fmt;
 pub enum RinfError {
     LockDartIsolate,
     NoDartIsolate,
-    BuildRuntime,
+    LockShutdownReceiver,
+    NoShutdownReceiver,
     LockMessageChannel,
     BrokenMessageChannel,
     ClosedMessageChannel,
@@ -24,8 +25,11 @@ impl fmt::Display for RinfError {
             RinfError::NoDartIsolate => {
                 write!(f, "Dart isolate for Rust signals was not created.")
             }
-            RinfError::BuildRuntime => {
-                write!(f, "Could not build the tokio runtime.")
+            RinfError::LockShutdownReceiver => {
+                write!(f, "Could not acquire the shutdown receiver lock.")
+            }
+            RinfError::NoShutdownReceiver => {
+                write!(f, "Shutdown receiver was not created.")
             }
             RinfError::LockMessageChannel => {
                 write!(f, "Could not acquire the message channel lock.")

rust_crate/src/interface.rs

@@ -1,5 +1,4 @@
 use crate::error::RinfError;
-use std::future::Future;
 
 #[cfg(not(target_family = "wasm"))]
 use super::interface_os::*;
@@ -27,23 +26,22 @@ pub struct DartSignal<T> {
 /// the `Runtime` object itself might be moved between threads,
 /// along with all the tasks it manages.
 #[cfg(not(target_family = "wasm"))]
-pub fn start_rust_logic<F, T>(main_future: F) -> Result<(), RinfError>
+pub fn start_rust_logic<F, T>(main_fn: F) -> Result<(), RinfError>
 where
-    F: Future<Output = T> + Send + 'static,
-    T: Send + 'static,
+    F: Fn() -> T + Send + 'static,
 {
-    start_rust_logic_real(main_future)
+    start_rust_logic_real(main_fn)
 }
 
 /// Runs the async main function in Rust.
 /// On the web, futures usually don't implement the `Send` trait
 /// because JavaScript environment is fundamentally single-threaded.
 #[cfg(target_family = "wasm")]
-pub fn start_rust_logic<F>(main_future: F) -> Result<(), RinfError>
+pub fn start_rust_logic<F, T>(main_fn: F) -> Result<(), RinfError>
 where
-    F: Future + 'static,
+    F: Fn() -> T + 'static,
 {
-    start_rust_logic_real(main_future)
+    start_rust_logic_real(main_fn)
 }
 
 /// Send a signal to Dart.