fix: treat default template of code as empty (langgenius#24106)

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

Author: Stream29

api/controllers/console/app/generator.py

@@ -12,6 +12,9 @@
 )
 from controllers.console.wraps import account_initialization_required, setup_required
 from core.errors.error import ModelCurrentlyNotSupportError, ProviderTokenNotInitError, QuotaExceededError
+from core.helper.code_executor.code_node_provider import CodeNodeProvider
+from core.helper.code_executor.javascript.javascript_code_provider import JavascriptCodeProvider
+from core.helper.code_executor.python3.python3_code_provider import Python3CodeProvider
 from core.llm_generator.llm_generator import LLMGenerator
 from core.model_runtime.errors.invoke import InvokeError
 from libs.login import login_required
@@ -123,9 +126,14 @@ def post(self):
         parser.add_argument("model_config", type=dict, required=True, nullable=False, location="json")
         parser.add_argument("ideal_output", type=str, required=False, default="", location="json")
         args = parser.parse_args()
-
+        providers: list[type[CodeNodeProvider]] = [Python3CodeProvider, JavascriptCodeProvider]
+        code_provider: type[CodeNodeProvider] | None = next(
+            (p for p in providers if p.is_accept_language(args["language"])), None
+        )
+        code_template = code_provider.get_default_code() if code_provider else ""
         try:
-            if args["current"] == "" and args["node_id"] != "":  # Generate from nothing for a workflow node
+            # Generate from nothing for a workflow node
+            if (args["current"] == code_template or args["current"] == "") and args["node_id"] != "":
                 from models import App, db
                 from services.workflow_service import WorkflowService