fix(secrets): admit periods inside Secret names, and rule out the edges

LanceDB namespace names permit periods, so excluding them here put Secrets out
of reach inside any namespace a user already has one in -- unreachable to
create, alter, describe, drop or bind, with no way to recover but renaming the
namespace.

A period is ruled out at either end instead, which is RFC 1123's shape and
Kubernetes' rule for object names. That stops `.` and `..` and anything reading
as a hidden file or a path fragment in a listing or an error. Nothing in the
layout depends on it -- the service encodes every segment -- so it buys
legibility rather than safety, and it is free only until a name is stored.

Names and path segments follow one rule: the two are joined nowhere, but a rule
that held for one and not the other would be worse than either.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UfmeJ533rQDnPBkMtjerV6

python/python/lancedb/secrets.py

@@ -14,7 +14,12 @@ from __future__ import annotations
 
 import re
 
-_SECRET_NAME = re.compile(r"^[A-Za-z0-9_-]{1,255}$")
+# Periods are legal inside a name: excluding them would put Secrets out of reach
+# of any namespace whose name carries one, which LanceDB namespaces allow. Not
+# at either end, which is RFC 1123's shape and Kubernetes' rule for object
+# names: it rules out `.` and `..` and anything that reads as a hidden file or a
+# path fragment in a listing. Matches the service, which rejects the same shapes.
+_SECRET_NAME = re.compile(r"^[A-Za-z0-9]([A-Za-z0-9_.-]{0,253}[A-Za-z0-9])?$")
 _ENV_VARIABLE = re.compile(r"^[A-Za-z_][A-Za-z0-9_]*$")
 
 

python/python/tests/test_first_class_function_slice2.py

@@ -281,6 +281,7 @@ def test_a_credential_value_is_rejected_in_the_binding_position():
         ("openai-prod", "not-a-var", "invalid environment variable name"),
         ("openai-prod", "API-TOKEN", "invalid environment variable name"),
         ("not a name", "API_TOKEN", "invalid Secret name"),
+        ("openai$prod", "API_TOKEN", "invalid Secret name"),
     ],
 )
 def test_a_binding_validates_both_names_locally(secret, variable, message):
@@ -288,6 +289,24 @@ def test_a_binding_validates_both_names_locally(secret, variable, message):
         EnvVarSecret(secret=secret, env_variable=variable)
 
 
+def test_a_period_is_legal_inside_a_name_and_not_at_its_edges():
+    """LanceDB namespaces already permit a period, so a Secret must be nameable
+    alongside them -- inside the name.
+
+    At either end it is ruled out instead, which is RFC 1123's shape and
+    Kubernetes' rule for object names: it stops `.` and `..` and anything that
+    reads as a hidden file or a path fragment in a listing. The service rejects
+    the same shapes, so this is a local answer to the same rule rather than a
+    second one.
+    """
+    binding = EnvVarSecret(secret="openai.prod.v1", env_variable="OPENAI_API_KEY")
+    assert binding.secret == "openai.prod.v1"
+
+    for name in [".", "..", ".hidden", "trailing.", "-lead", "trail-", "_x"]:
+        with pytest.raises(ValueError, match="invalid Secret name"):
+            EnvVarSecret(secret=name, env_variable="OPENAI_API_KEY")
+
+
 def _main_udf_source(
     *, threshold: int = 20, input_annotation: str = "int", comparison: str = ">="
 ) -> str:

rust/lancedb/src/remote/client.rs

@@ -412,7 +412,7 @@ fn validate_dns_hostname(hostname: &str) -> Result<()> {
 /// remembering to extend this. Every secrets route is denied, not only the two
 /// that carry a value: their bodies hold names and page tokens, which are worth
 /// nothing in a debug log next to the risk of a new verb landing here unnoticed.
-pub(crate) fn route_carries_credential(path: &str) -> bool {
+fn route_carries_credential(path: &str) -> bool {
     path.split('/').any(|segment| segment == "secrets")
 }