Planning: using rule-based model when data based data is empty

modules/planning/conf/scenario/lane_follow_hybrid_config.pb.txt

@@ -29,6 +29,7 @@ stage_config: {
       cpu_model_file: "/apollo/modules/planning/data/model/cpu_test_model_cnn.pt"
       gpu_model_file: "/apollo/modules/planning/data/model/gpu_test_model_cnn.pt"
       use_cuda: true
+      allow_empty_learning_based_data: true
       allow_empty_output_trajectory: true
     }
   }

modules/planning/proto/task_config.proto

@@ -54,7 +54,8 @@ message LearningModelInferenceTaskConfig {
   optional bool use_cuda = 4 [default = true];
   // delta_t depends on the model output, not a configurable value here
   optional double trajectory_delta_t = 5 [default = 0.2];  // second
-  optional bool allow_empty_output_trajectory = 6 [default = false];
+  optional bool allow_empty_learning_based_data = 6 [default = false];
+  optional bool allow_empty_output_trajectory = 7 [default = false];
 }
 
 //////////////////////////////////

modules/planning/tasks/learning_model/learning_model_inference_task.cc

@@ -62,6 +62,11 @@ Status LearningModelInferenceTask::Process(Frame* frame) {
       !injector_->learning_based_data()->GetLatestLearningDataFrame()) {
     const std::string msg = "learning_data_frame empty";
     AERROR << msg;
+    // hybrid model will use rule based planning when learning based data or
+    // learning data frame is empty
+    if (config.allow_empty_learning_based_data()) {
+      return Status::OK();
+    }
     return Status(ErrorCode::PLANNING_ERROR, msg);
   }