host: expose harness state and actions over the world API

host/src/harness/input.rs

@@ -15,6 +15,14 @@ pub enum Input {
         #[serde(rename = "requestId")]
         request_id: String,
     },
+    Api {
+        id: String,
+        method: String,
+        path: String,
+        body: Value,
+        #[serde(skip)]
+        reply: mpsc::UnboundedSender<Value>,
+    },
     Stop,
 }
 
@@ -31,8 +39,20 @@ pub(super) struct Inbox(pub tokio::sync::Mutex<Receiver>);
 #[serde]
 pub async fn op_input(state: Rc<RefCell<OpState>>) -> Result<serde_json::Value, JsErrorBox> {
     let inbox = state.borrow().borrow::<Rc<Inbox>>().clone();
-    serde_json::to_value(inbox.0.lock().await.recv().await)
-        .map_err(|error| JsErrorBox::generic(error.to_string()))
+    let input = inbox.0.lock().await.recv().await;
+    if let Some(Input::Api { id, reply, .. }) = &input {
+        state
+            .borrow_mut()
+            .borrow_mut::<super::http::Replies>()
+            .insert(
+                id.clone(),
+                super::http::Reply {
+                    sender: reply.clone(),
+                    finished: Default::default(),
+                },
+            );
+    }
+    serde_json::to_value(input).map_err(|error| JsErrorBox::generic(error.to_string()))
 }
 
 pub(super) fn console(sender: Sender) {