sdk: readable clients (no Empty wrapper, no unused error module), documented examples with tests

sdk/tests/plugins/probe/src/main.rs

@@ -28,6 +28,32 @@ impl Probe {
     async fn serve(&self) -> Result<()> {
         sausage_plugin::listen("/endpoint", std::rc::Rc::new(Control)).await
     }
+    /// Forward detached progress through the real core.
+    async fn relay(&self) -> Result<i32> {
+        call("probe.progress", json!({}))
+            .detach()
+            .on_notify(move |name, params| {
+                Ctx::default().notify(name, params).unwrap();
+            })
+            .await
+            .map(|value| value.as_i64().unwrap() as i32)
+    }
+    /// Send progress before the final result.
+    fn progress(&self, ctx: &Ctx) -> Result<i32> {
+        ctx.notify("step", json!({"done":true}))?;
+        Ok(42)
+    }
+    /// Start a detached service that survives this caller.
+    async fn launch(&self) -> Result<String> {
+        Ok(sausage_plugin::serde_json::from_value(
+            call("probe.service", json!({})).detach().await?,
+        )?)
+    }
+    /// Keep the process alive until the core closes stdin.
+    async fn service(&self) -> Result<String> {
+        sausage_plugin::listen("/state/control", std::rc::Rc::new(Control)).await?;
+        Ok(sausage_plugin::pid())
+    }
     /// Add two numbers.
     ///
     /// The result is their sum.