Unify and optimize MCP env-var interpolation regex

Fixes on record

Merged to main. A stamp counts the issues a fix is linked to.

• #26240 fix(mcp): pre-compile env-var regex and unify interpolation

  merged to main

  files: hermes_cli/mcp_config.py, scripts/release.py, tools/mcp_tool.py

  Show the diff

  • hermes_cli/mcp_config.py

    @@ -25,6 +25,7 @@
     )
     from hermes_cli.colors import Colors, color
     from hermes_constants import display_hermes_home
    +from tools.mcp_tool import _ENV_VAR_PATTERN
     
     logger = logging.getLogger(__name__)
     
    @@ -551,7 +552,7 @@ def cmd_mcp_test(args):
             for k, v in headers.items():
                 if isinstance(v, str) and ("key" in k.lower() or "auth" in k.lower()):
                     # Mask the value
    -                resolved = _interpolate_value(v)
    +                resolved = _ENV_VAR_PATTERN.sub(lambda m: os.getenv(m.group(1), ""), v)
                     if len(resolved) > 8:
                         masked = resolved[:4] + "***" + resolved[-4:]
                     else:
    @@ -581,13 +582,6 @@ def cmd_mcp_test(args):
         print()
     
     
    -def _interpolate_value(value: str) -> str:
    -    """Resolve ``${ENV_VAR}`` references in a string."""
    -    def _replace(m):
    -        return os.getenv(m.group(1), "")
    -    return re.sub(r"\$\{(\w+)\}", _replace, value)
    -
    -
     # ─── hermes mcp login ────────────────────────────────────────────────────────
     
     def cmd_mcp_login(args):

  • scripts/release.py

    @@ -111,6 +111,7 @@
         "[email protected]": "oswaldb22",
         "[redacted:email]": "AJV20",
         "[redacted:email]": "masonjames",
    +    "[email protected]": "amethystani",
         "[redacted:email]": "liquidchen",
         "[redacted:email]": "subtract0",
         "[redacted:email]": "ReqX",

  • tools/mcp_tool.py

    @@ -279,6 +279,11 @@ def _check_message_handler_support() -> bool:
         re.IGNORECASE,
     )
     
    +# Pre-compiled pattern for ${VAR_NAME} style env-var interpolation.
    +# Supports any non-} characters in the variable name (hyphens, dots, etc.)
    +# so providers like MY-VAR or my.var work correctly.
    +_ENV_VAR_PATTERN = re.compile(r"\$\{([^}]+)\}")
    +
     
     # ---------------------------------------------------------------------------
     # Security helpers
    @@ -2104,7 +2109,7 @@ def _interpolate_env_vars(value):
         if isinstance(value, str):
             def _replace(m):
                 return os.environ.get(m.group(1), m.group(0))
    -        return re.sub(r"\$\{([^}]+)\}", _replace, value)
    +        return _ENV_VAR_PATTERN.sub(_replace, value)
         if isinstance(value, dict):
             return {k: _interpolate_env_vars(v) for k, v in value.items()}
         if isinstance(value, list):