fix: deliver order_changed pushes from real server format (topic private, event/data wrapper)

Author: gilbertwong96

lib/longbridge/trade_context.ex

@@ -777,13 +777,21 @@ defmodule Longbridge.TradeContext do
   defp dispatch_push({:push, 18, body}, callbacks, default_callback) do
     notif = Protox.decode!(body, Longbridge.Trade.V1.Notification)
 
-    if notif.topic != "" and notif.content_type == :CONTENT_JSON and notif.data != "" do
+    if notif.topic != "" and notif.data != "" do
       case JSON.decode(notif.data) do
         {:ok, event} ->
+          event = unwrap_order_changed(event)
+
           if callback = Map.get(callbacks, notif.topic) do
             callback.(event)
           else
-            if default_callback, do: default_callback.(event)
+            # The server echoes the subscribed topic ("private") on pushes,
+            # while callbacks are registered under the canonical topic path.
+            if callback = Map.get(callbacks, @order_changed_topic) do
+              callback.(event)
+            else
+              if default_callback, do: default_callback.(event)
+            end
           end
 
         _ ->
@@ -802,4 +810,7 @@ defmodule Longbridge.TradeContext do
   end
 
   defp dispatch_push(_other, _callbacks, _default), do: :ok
+
+  defp unwrap_order_changed(%{"event" => "order_changed_lb", "data" => %{} = data}), do: data
+  defp unwrap_order_changed(event), do: event
 end

test/longbridge/trade_push_test.exs

@@ -89,6 +89,54 @@ defmodule Longbridge.TradePushTest do
       Process.exit(ctx, :kill)
     end
 
+    test "delivers pushes whose topic echoes the subscription (private) with event/data wrapper" do
+      event_json =
+        JSON.encode!(%{
+          "event" => "order_changed_lb",
+          "data" => %{
+            "order_id" => "424242",
+            "symbol" => "700.HK",
+            "status" => "FilledStatus",
+            "executed_quantity" => "200",
+            "executed_price" => "50.5"
+          }
+        })
+
+      notification = %Longbridge.Trade.V1.Notification{
+        topic: "private",
+        content_type: :CONTENT_JSON,
+        dispatch_type: :DISPATCH_DIRECT,
+        data: event_json
+      }
+
+      config =
+        Config.new(
+          token: "test-token",
+          http_url: "http://127.0.0.1:1"
+        )
+
+      {:ok, ctx} = TradeContext.start_link(config, skip_connection: true)
+      Process.sleep(50)
+
+      parent = self()
+
+      TradeContext.set_on_order_changed(
+        ctx,
+        fn event -> send(parent, {:trade_event, event}) end
+      )
+
+      push_msg = {:push, 18, encode_notification(notification)}
+      send(ctx, {:longbridge, ctx, push_msg})
+
+      assert_receive {:trade_event, event}, 2_000
+      assert event["order_id"] == "424242"
+      assert event["status"] == "FilledStatus"
+      assert event["executed_quantity"] == "200"
+      assert event["executed_price"] == "50.5"
+
+      Process.exit(ctx, :kill)
+    end
+
     test "ignores non-JSON content type" do
       notification = %Longbridge.Trade.V1.Notification{
         topic: "/v1/trade/order_changed",