[FIX] remove hard-coded main module finding at runserver cmd

Author: bnbong

src/fastapi_fastkit/cli.py

@@ -819,6 +819,20 @@ def deleteproject(ctx: Context, project_name: str) -> None:
         print_error(f"Error during project deletion: {e}")
 
 
+def _derive_app_module(project_dir: str, main_path: str) -> str:
+    """Convert a discovered ``main.py`` path into a uvicorn ``module:attr``.
+
+    Templates can place ``main.py`` anywhere under the project (``main.py``,
+    ``src/main.py``, ``src/app/main.py``, ...). The previous ``"src/"`` /
+    ``""`` heuristic mis-mapped the domain-starter layout (``src/app/main.py``
+    → wrongly produced ``src.main:app``); deriving the dotted path from the
+    actual relative location avoids that drift for any future layout too.
+    """
+    rel_path = os.path.relpath(main_path, project_dir)
+    module_part = os.path.splitext(rel_path)[0].replace(os.sep, ".")
+    return f"{module_part}:app"
+
+
 @fastkit_cli.command()
 @click.option(
     "--host",
@@ -893,10 +907,7 @@ def runserver(
         return
 
     main_path = core_modules["main"]
-    if "src/" in main_path:
-        app_module = "src.main:app"
-    else:
-        app_module = "main:app"
+    app_module = _derive_app_module(project_dir, main_path)
 
     if venv_python:
         print_info(f"Using Python from virtual environment: {venv_python}")

tests/test_cli_operations/test_cli.py

@@ -646,6 +646,26 @@ def test_runserver_no_venv_project(self, temp_dir: str) -> None:
         assert result.exit_code == 0
         assert "Virtual environment not found" in result.output
 
+    def test_derive_app_module_handles_all_supported_layouts(self) -> None:
+        """Regression: nested layouts like src/app/main.py must map correctly.
+
+        ``runserver`` previously mapped any ``src/`` main file to
+        ``src.main:app``, which silently mis-targeted the
+        ``fastapi-domain-starter`` layout (``src/app/main.py``).
+        """
+        from fastapi_fastkit.cli import _derive_app_module
+
+        proj = "/proj"
+        assert _derive_app_module(proj, os.path.join(proj, "main.py")) == "main:app"
+        assert (
+            _derive_app_module(proj, os.path.join(proj, "src", "main.py"))
+            == "src.main:app"
+        )
+        assert (
+            _derive_app_module(proj, os.path.join(proj, "src", "app", "main.py"))
+            == "src.app.main:app"
+        )
+
     def test_addroute_command(self, temp_dir: str) -> None:
         # given
         os.chdir(temp_dir)