[runtime env] Validate "excludes" field (#19302)

python/ray/_private/runtime_env/validation.py

@@ -144,6 +144,27 @@ def parse_and_validate_container(container: List[str],
     return container
 
 
+def parse_and_validate_excludes(excludes: List[str],
+                                is_task_or_actor: bool = False) -> List[str]:
+    """Parses and validates a user-provided 'excludes' option.
+
+    This is validated to verify that it is of type List[str].
+
+    If an empty list is passed, we return `None` for consistency.
+    """
+    assert excludes is not None
+
+    if isinstance(excludes, list) and len(excludes) == 0:
+        return None
+
+    if (isinstance(excludes, list)
+            and all(isinstance(path, str) for path in excludes)):
+        return excludes
+    else:
+        raise TypeError("runtime_env['excludes'] must be of type "
+                        f"List[str], got {type(excludes)}")
+
+
 def parse_and_validate_env_vars(env_vars: Dict[str, str],
                                 is_task_or_actor: bool = False
                                 ) -> Optional[Dict[str, str]]:
@@ -170,6 +191,7 @@ def parse_and_validate_env_vars(env_vars: Dict[str, str],
 # validate them.
 OPTION_TO_VALIDATION_FN = {
     "working_dir": parse_and_validate_working_dir,
+    "excludes": parse_and_validate_excludes,
     "conda": parse_and_validate_conda,
     "pip": parse_and_validate_pip,
     "uris": parse_and_validate_uris,

python/ray/tests/test_runtime_env_validation.py

@@ -6,8 +6,9 @@ from pathlib import Path
 import yaml
 
 from ray._private.runtime_env.validation import (
-    parse_and_validate_working_dir, parse_and_validate_conda,
+    parse_and_validate_excludes, parse_and_validate_working_dir,
-    parse_and_validate_pip, parse_and_validate_env_vars, ParsedRuntimeEnv,
+    parse_and_validate_conda, parse_and_validate_pip,
+    parse_and_validate_env_vars, ParsedRuntimeEnv,
     override_task_or_actor_runtime_env)
 
 CONDA_DICT = {"dependencies": ["pip", {"pip": ["pip-install-test==0.5"]}]}
@@ -83,6 +84,24 @@ class TestValidateWorkingDir:
                 }, is_task_or_actor=True)
 
 
+class TestValidateExcludes:
+    def test_validate_excludes_invalid_types(self):
+        with pytest.raises(TypeError):
+            parse_and_validate_excludes(1)
+
+        with pytest.raises(TypeError):
+            parse_and_validate_excludes(True)
+
+        with pytest.raises(TypeError):
+            parse_and_validate_excludes("string")
+
+        with pytest.raises(TypeError):
+            parse_and_validate_excludes(["string", 1])
+
+    def test_validate_excludes_empty_list(self):
+        assert ParsedRuntimeEnv({"excludes": []}) == {}
+
+
 @pytest.mark.skipif(
     sys.platform == "win32", reason="Conda option not supported on Windows.")
 class TestValidateConda: