fix(bar): handle ipc connection errors.

Try to use the default bar id (`bar-0`) if none is set.

src/bar.cpp

@@ -61,6 +61,7 @@ const Bar::bar_mode_map Bar::PRESET_MODES = {  //
 
 const std::string_view Bar::MODE_DEFAULT = "default";
 const std::string_view Bar::MODE_INVISIBLE = "invisible";
+const std::string_view DEFAULT_BAR_ID = "bar-0";
 
 #ifdef HAVE_GTK_LAYER_SHELL
 struct GLSSurfaceImpl : public BarSurface, public sigc::trackable {
@@ -556,7 +557,14 @@ waybar::Bar::Bar(struct waybar_output* w_output, const Json::Value& w_config)
     if (auto id = config["id"]; id.isString()) {
       bar_id = id.asString();
     }
+    if (bar_id.empty()) {
+      bar_id = DEFAULT_BAR_ID;
+    }
+    try {
       _ipc_client = std::make_unique<BarIpcClient>(*this);
+    } catch (const std::exception& exc) {
+      spdlog::warn("Failed to open bar ipc connection: {}", exc.what());
+    }
   }
 #endif
 

src/modules/sway/bar.cpp

@@ -3,6 +3,8 @@
 #include <fmt/ostream.h>
 #include <spdlog/spdlog.h>
 
+#include <stdexcept>
+
 #include "bar.hpp"
 #include "modules/sway/ipc/ipc.hpp"
 
@@ -47,13 +49,13 @@ struct swaybar_config parseConfig(const Json::Value& payload) {
 }
 
 void BarIpcClient::onInitialConfig(const struct Ipc::ipc_response& res) {
-  try {
   auto payload = parser_.parse(res.payload);
+  if (auto success = payload.get("success", true); !success.asBool()) {
+    auto err = payload.get("error", "Unknown error");
+    throw std::runtime_error(err.asString());
+  }
   auto config = parseConfig(payload);
   onConfigUpdate(config);
-  } catch (const std::exception& e) {
-    spdlog::error("BarIpcClient::onInitialConfig {}", e.what());
-  }
 }
 
 void BarIpcClient::onIpcEvent(const struct Ipc::ipc_response& res) {