Initial commit

src/lib.rs

@@ -0,0 +1,53 @@
+#[macro_use]
+extern crate napi;
+#[macro_use]
+extern crate napi_derive;
+
+use std::convert::TryInto;
+
+use napi::{CallContext, Env, JsNumber, JsObject, Module, Result, Task};
+
+#[cfg(all(unix, not(target_env = "musl")))]
+#[global_allocator]
+static ALLOC: jemallocator::Jemalloc = jemallocator::Jemalloc;
+
+register_module!(example, init);
+
+struct AsyncTask(u32);
+
+impl Task for AsyncTask {
+  type Output = u32;
+  type JsValue = JsNumber;
+
+  fn compute(&mut self) -> Result<Self::Output> {
+    use std::thread::sleep;
+    use std::time::Duration;
+    sleep(Duration::from_millis(self.0 as u64));
+    Ok(self.0 * 2)
+  }
+
+  fn resolve(&self, env: &mut Env, output: Self::Output) -> Result<Self::JsValue> {
+    env.create_uint32(output)
+  }
+}
+
+fn init(module: &mut Module) -> Result<()> {
+  module.create_named_method("sync", sync_fn)?;
+
+  module.create_named_method("sleep", sleep)?;
+  Ok(())
+}
+
+#[js_function(1)]
+fn sync_fn(ctx: CallContext) -> Result<JsNumber> {
+  let argument: u32 = ctx.get::<JsNumber>(0)?.try_into()?;
+
+  ctx.env.create_uint32(argument + 100)
+}
+
+#[js_function(1)]
+fn sleep(ctx: CallContext) -> Result<JsObject> {
+  let argument: u32 = ctx.get::<JsNumber>(0)?.try_into()?;
+  let task = AsyncTask(argument);
+  ctx.env.spawn(task)
+}