Hermes-agent

tools/managed_tool_gateway.py

@@ -0,0 +1,192 @@
+"""Generic managed-tool gateway helpers for Nous-hosted vendor passthroughs."""
+
+from __future__ import annotations
+
+import json
+import logging
+import os
+from datetime import datetime, timezone
+from dataclasses import dataclass
+from typing import Callable, Optional
+
+logger = logging.getLogger(__name__)
+
+from hermes_constants import get_hermes_home
+from tools.tool_backend_helpers import managed_nous_tools_enabled
+
+_DEFAULT_TOOL_GATEWAY_DOMAIN = "nousresearch.com"
+_DEFAULT_TOOL_GATEWAY_SCHEME = "https"
+_NOUS_ACCESS_TOKEN_REFRESH_SKEW_SECONDS = 120
+
+
+@dataclass(frozen=True)
+class ManagedToolGatewayConfig:
+    vendor: str
+    gateway_origin: str
+    nous_user_token: str
+    managed_mode: bool
+
+
+def auth_json_path():
+    """Return the Hermes auth store path, respecting HERMES_HOME overrides."""
+    return get_hermes_home() / "auth.json"
+
+
+def _read_nous_provider_state() -> Optional[dict]:
+    try:
+        path = auth_json_path()
+        if not path.is_file():
+            return None
+        data = json.loads(path.read_text())
+        providers = data.get("providers", {})
+        if not isinstance(providers, dict):
+            return None
+        nous_provider = providers.get("nous", {})
+        if isinstance(nous_provider, dict):
+            return nous_provider
+    except Exception:
+        pass
+    return None
+
+
+def _parse_timestamp(value: object) -> Optional[datetime]:
+    if not isinstance(value, str) or not value.strip():
+        return None
+    normalized = value.strip()
+    if normalized.endswith("Z"):
+        normalized = normalized[:-1] + "+00:00"
+    try:
+        parsed = datetime.fromisoformat(normalized)
+    except ValueError:
+        return None
+    if parsed.tzinfo is None:
+        parsed = parsed.replace(tzinfo=timezone.utc)
+    return parsed.astimezone(timezone.utc)
+
+
+def _access_token_is_expiring(expires_at: object, skew_seconds: int) -> bool:
+    expires = _parse_timestamp(expires_at)
+    if expires is None:
+        return True
+    remaining = (expires - datetime.now(timezone.utc)).total_seconds()
+    return remaining <= max(0, int(skew_seconds))
+
+
+def peek_nous_access_token() -> Optional[str]:
+    """Cheap probe for a Nous gateway token without triggering refresh.
+
+    Availability scans (`hermes tools`, banner/status paint, provider
+    `is_available()` checks) must stay off the synchronous OAuth refresh path.
+    This helper therefore only inspects the explicit env override and the
+    cached auth-store token, without checking expiry and without making any
+    network calls. Truthful refresh handling stays in request/session paths
+    that call :func:`read_nous_access_token`.
+    """
+    explicit = os.getenv("TOOL_GATEWAY_USER_TOKEN")
+    if isinstance(explicit, str) and explicit.strip():
+        return explicit.strip()
+
+    nous_provider = _read_nous_provider_state() or {}
+    access_token = nous_provider.get("access_token")
+    if isinstance(access_token, str) and access_token.strip():
+        return access_token.strip()
+    return None
+
+
+def read_nous_access_token() -> Optional[str]:
+    """Read a Nous Subscriber OAuth access token from auth store or env override."""
+    explicit = os.getenv("TOOL_GATEWAY_USER_TOKEN")
+    if isinstance(explicit, str) and explicit.strip():
+        return explicit.strip()
+    nous_provider = _read_nous_provider_state() or {}
+    cached_token = peek_nous_access_token()
+
+    if cached_token and not _access_token_is_expiring(
+        nous_provider.get("expires_at"),
+        _NOUS_ACCESS_TOKEN_REFRESH_SKEW_SECONDS,
+    ):
+        return cached_token
+
+    try:
+        from hermes_cli.auth import resolve_nous_access_token
+
+        refreshed_token = resolve_nous_access_token(
+            refresh_skew_seconds=_NOUS_ACCESS_TOKEN_REFRESH_SKEW_SECONDS,
+        )
+        if isinstance(refreshed_token, str) and refreshed_token.strip():
+            return refreshed_token.strip()
+    except Exception as exc:
+        logger.debug("Nous access token refresh failed: %s", exc)
+
+    return cached_token
+
+
+def get_tool_gateway_scheme() -> str:
+    """Return configured shared gateway URL scheme."""
+    scheme = os.getenv("TOOL_GATEWAY_SCHEME", "").strip().lower()
+    if not scheme:
+        return _DEFAULT_TOOL_GATEWAY_SCHEME
+
+    if scheme in {"http", "https"}:
+        return scheme
+
+    raise ValueError("TOOL_GATEWAY_SCHEME must be 'http' or 'https'")
+
+
+def build_vendor_gateway_url(vendor: str) -> str:
+    """Return the gateway origin for a specific vendor."""
+    vendor_key = f"{vendor.upper().replace('-', '_')}_GATEWAY_URL"
+    explicit_vendor_url = os.getenv(vendor_key, "").strip().rstrip("/")
+    if explicit_vendor_url:
+        return explicit_vendor_url
+
+    shared_scheme = get_tool_gateway_scheme()
+    shared_domain = os.getenv("TOOL_GATEWAY_DOMAIN", "").strip().strip("/")
+    if shared_domain:
+        return f"{shared_scheme}://{vendor}-gateway.{shared_domain}"
+
+    return f"{shared_scheme}://{vendor}-gateway.{_DEFAULT_TOOL_GATEWAY_DOMAIN}"
+
+
+def resolve_managed_tool_gateway(
+    vendor: str,
+    gateway_builder: Optional[Callable[[str], str]] = None,
+    token_reader: Optional[Callable[[], Optional[str]]] = None,
+) -> Optional[ManagedToolGatewayConfig]:
+    """Resolve shared managed-tool gateway config for a vendor."""
+    if not managed_nous_tools_enabled():
+        return None
+
+    resolved_gateway_builder = gateway_builder or build_vendor_gateway_url
+    resolved_token_reader = token_reader or read_nous_access_token
+
+    gateway_origin = resolved_gateway_builder(vendor)
+    nous_user_token = resolved_token_reader()
+    if not gateway_origin or not nous_user_token:
+        return None
+
+    return ManagedToolGatewayConfig(
+        vendor=vendor,
+        gateway_origin=gateway_origin,
+        nous_user_token=nous_user_token,
+        managed_mode=True,
+    )
+
+
+def is_managed_tool_gateway_ready(
+    vendor: str,
+    gateway_builder: Optional[Callable[[str], str]] = None,
+    token_reader: Optional[Callable[[], Optional[str]]] = None,
+) -> bool:
+    """Return True when gateway URL and a likely-usable Nous token are present.
+
+    Defaults to :func:`peek_nous_access_token` so read-only availability scans
+    avoid synchronous OAuth refresh. Callers that are about to make a real
+    gateway request should use :func:`resolve_managed_tool_gateway` (which
+    still defaults to the refresh-aware :func:`read_nous_access_token`).
+    """
+    return resolve_managed_tool_gateway(
+        vendor,
+        gateway_builder=gateway_builder,
+        token_reader=token_reader or peek_nous_access_token,
+    ) is not None