add sanitizer function (#30919)

* sanetizer function

* spelling

* better

* move to helpers

selfdrive/test/helpers.py

@@ -8,6 +8,7 @@ from openpilot.common.params import Params
 from openpilot.selfdrive.manager.process_config import managed_processes
 from openpilot.system.hardware import PC
 from openpilot.system.version import training_version, terms_version
+from openpilot.tools.lib.logreader import LogIterable
 
 
 def set_params_enabled():
@@ -79,3 +80,11 @@ def read_segment_list(segment_list_path):
     seg_list = f.read().splitlines()
 
   return [(platform[2:], segment) for platform, segment in zip(seg_list[::2], seg_list[1::2], strict=True)]
+
+
+# Utilities for sanitizing routes of only essential data for testing car ports and doing validation.
+
+PRESERVE_SERVICES = ["can", "carParams", "pandaStates", "pandaStateDEPRECATED"]
+
+def sanitize(lr: LogIterable) -> LogIterable:
+  return filter(lambda msg: msg.which() in PRESERVE_SERVICES, lr)