Native plugins support

Cargo.toml

@@ -35,6 +35,7 @@ lunatic-distributed-api = { workspace = true }
 lunatic-error-api = { workspace = true }
 lunatic-messaging-api = { workspace = true }
 lunatic-networking-api = { workspace = true }
+lunatic-plugin-internal = { workspace = true }
 lunatic-process = { workspace = true }
 lunatic-process-api = { workspace = true }
 lunatic-registry-api = { workspace = true }
@@ -73,13 +74,19 @@ members = [
     "crates/lunatic-distributed",
     "crates/lunatic-error-api",
     "crates/lunatic-messaging-api",
+    "crates/lunatic-plugin-internal",
+    "crates/lunatic-plugin",
     "crates/lunatic-process-api",
     "crates/lunatic-process",
     "crates/lunatic-registry-api",
     "crates/lunatic-stdout-capture",
     "crates/lunatic-timer-api",
     "crates/lunatic-version-api",
     "crates/lunatic-wasi-api",
+
+    # Examples
+    "examples/counter-guest",
+    "examples/counter-plugin",
 ]
 
 [workspace.dependencies]
@@ -90,9 +97,12 @@ lunatic-distributed-api = { path = "crates/lunatic-distributed-api", version = "
 lunatic-error-api = { path = "crates/lunatic-error-api", version = "0.12" }
 lunatic-messaging-api = { path = "crates/lunatic-messaging-api", version = "0.12" }
 lunatic-networking-api = { path = "crates/lunatic-networking-api", version = "0.12" }
+lunatic-plugin = { path = "crates/lunatic-plugin", version = "0.12" }
+lunatic-plugin-internal = { path = "crates/lunatic-plugin-internal", version = "0.12" }
 lunatic-process = { path = "crates/lunatic-process", version = "0.12" }
 lunatic-process-api = { path = "crates/lunatic-process-api", version = "0.12" }
 lunatic-registry-api = { path = "crates/lunatic-registry-api", version = "0.12" }
+lunatic-runtime = { path = ".", version = "0.12" }
 lunatic-stdout-capture = { path = "crates/lunatic-stdout-capture", version = "0.12" }
 lunatic-timer-api = { path = "crates/lunatic-timer-api", version = "0.12" }
 lunatic-version-api = { path = "crates/lunatic-version-api", version = "0.12" }

benches/benchmark.rs

@@ -15,11 +15,12 @@ fn criterion_benchmark(c: &mut Criterion) {
     let config = Arc::new(DefaultProcessConfig::default());
     let wasmtime_config = default_config();
     let runtime = WasmtimeRuntime::new(&wasmtime_config).unwrap();
+    let plugins = Arc::new(vec![]);
 
     let raw_module = wat::parse_file("./wat/hello.wat").unwrap();
     let module = Arc::new(
         runtime
-            .compile_module::<DefaultProcessState>(raw_module.into())
+            .compile_module::<DefaultProcessState>(&plugins, raw_module.into())
             .unwrap(),
     );
 
@@ -34,6 +35,7 @@ fn criterion_benchmark(c: &mut Criterion) {
                 module.clone(),
                 config.clone(),
                 registry,
+                plugins.clone(),
             )
             .unwrap();
             lunatic_process::wasm::spawn_wasm(

crates/lunatic-distributed/Cargo.toml

@@ -8,6 +8,7 @@ repository = "https://github.com/lunatic-solutions/lunatic/tree/main/crates"
 license = "Apache-2.0/MIT"
 
 [dependencies]
+lunatic-plugin-internal = { workspace = true }
 lunatic-process = { workspace = true }
 
 anyhow = { workspace = true }

crates/lunatic-distributed/src/distributed/server.rs

@@ -2,6 +2,7 @@ use std::{net::SocketAddr, sync::Arc};
 
 use anyhow::{anyhow, Result};
 
+use lunatic_plugin_internal::Plugin;
 use lunatic_process::{
     env::{Environment, Environments},
     message::{DataMessage, Message},
@@ -25,6 +26,7 @@ pub struct ServerCtx<T, E: Environment> {
     pub modules: Modules<T>,
     pub distributed: DistributedProcessState,
     pub runtime: WasmtimeRuntime,
+    pub plugins: Arc<Vec<Plugin>>,
 }
 
 impl<T: 'static, E: Environment> Clone for ServerCtx<T, E> {
@@ -34,6 +36,7 @@ impl<T: 'static, E: Environment> Clone for ServerCtx<T, E> {
             modules: self.modules.clone(),
             distributed: self.distributed.clone(),
             runtime: self.runtime.clone(),
+            plugins: self.plugins.clone(),
         }
     }
 }
@@ -159,7 +162,9 @@ where
         None => {
             if let Some(bytes) = ctx.distributed.control.get_module(module_id).await {
                 let wasm = RawWasm::new(Some(module_id), bytes);
-                ctx.modules.compile(ctx.runtime.clone(), wasm).await??
+                ctx.modules
+                    .compile(ctx.runtime.clone(), ctx.plugins.clone(), wasm)
+                    .await??
             } else {
                 return Ok(Err(ClientError::ModuleNotFound));
             }

crates/lunatic-plugin-internal/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "lunatic-plugin-internal"
+version = "0.12.0"
+edition = "2021"
+description = "Lunatic plugins system."
+homepage = "https://lunatic.solutions"
+repository = "https://github.com/lunatic-solutions/lunatic/tree/main/crates"
+license = "Apache-2.0/MIT"
+
+[dependencies]
+anyhow = { workspace = true }
+libloading = "0.7"
+wasmtime = { workspace = true }

crates/lunatic-plugin-internal/src/lib.rs

@@ -0,0 +1,66 @@
+use std::{
+    any::{Any, TypeId},
+    ffi::OsStr,
+    sync::Arc,
+};
+
+use anyhow::{Context, Result};
+use libloading::{Library, Symbol};
+use wasmtime::Linker;
+
+type PluginIDFn = unsafe extern "C" fn() -> TypeId;
+type InitFn = unsafe extern "C" fn() -> Box<dyn Any + Send + Sync>;
+type RegisterFn<T> = unsafe extern "C" fn(linker: &mut Linker<T>) -> Result<()>;
+
+pub struct Plugin {
+    id: TypeId,
+    lib: Library,
+}
+
+pub trait PluginCtx {
+    fn plugins(&self) -> &Arc<Vec<Plugin>>;
+    fn plugin_state<T: 'static>(&self, plugin: &TypeId) -> Option<&T>;
+    fn plugin_state_mut<T: 'static>(&mut self, plugin: &TypeId) -> Option<&mut T>;
+}
+
+impl Plugin {
+    /// Loads a dynamic library as a plugin.
+    ///
+    /// # Safety
+    ///
+    /// Plugins must specify the correct type of the exported functions.
+    pub unsafe fn new<P: AsRef<OsStr>>(filename: P) -> Result<Self> {
+        let lib = Library::new(filename)?;
+        let plugin_id: Symbol<PluginIDFn> = lib
+            .get(b"plugin_id")
+            .context("loading `plugin_id` export from plugin")?;
+        Ok(Plugin {
+            id: plugin_id(),
+            lib,
+        })
+    }
+
+    pub fn id(&self) -> TypeId {
+        self.id
+    }
+
+    pub fn init(&self) -> Result<Box<dyn Any + Send + Sync>> {
+        unsafe {
+            let init: Symbol<InitFn> = self
+                .lib
+                .get(b"init")
+                .context("loading `init` export from plugin")?;
+            Ok(init())
+        }
+    }
+
+    pub fn register<T>(&self, linker: &mut Linker<T>) -> Result<()> {
+        unsafe {
+            let register: Symbol<RegisterFn<T>> = self
+                .lib
+                .get(b"register")
+                .context("loading `register` export from plugin")?;
+            register(linker).context("calling register on plugin")
+        }
+    }
+}

crates/lunatic-plugin/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "lunatic-plugin"
+version = "0.12.0"
+edition = "2021"
+description = "Lunatic plugins system."
+homepage = "https://lunatic.solutions"
+repository = "https://github.com/lunatic-solutions/lunatic/tree/main/crates"
+license = "Apache-2.0/MIT"
+
+[dependencies]
+lunatic-plugin-internal = { workspace = true }
+lunatic-runtime = { workspace = true }
+
+anyhow = { workspace = true }
+wasmtime = { workspace = true }