merge: testing → main (reconcile 2-week divergence)

decnet/geoip/factory.py

@@ -0,0 +1,47 @@
+"""GeoIP provider factory.
+
+Dispatch key: ``DECNET_GEOIP_PROVIDER`` (default ``rir``). Lazy singleton,
+same shape as :func:`decnet.bus.factory.get_bus`.
+
+MVP wires only the RIR provider. ``dbip`` and ``maxmind`` slots are
+reserved and raise :class:`NotImplementedError` until their subpackages
+land.
+"""
+from __future__ import annotations
+
+import os
+from typing import Optional
+
+from decnet.geoip.base import Provider
+
+_cached: Optional[Provider] = None
+_cached_key: Optional[str] = None
+
+
+def get_provider() -> Provider:
+    """Return the configured :class:`Provider` singleton."""
+    global _cached, _cached_key
+    key = os.environ.get("DECNET_GEOIP_PROVIDER", "rir").lower()
+    if _cached is not None and _cached_key == key:
+        return _cached
+
+    if key == "rir":
+        from decnet.geoip.rir.provider import RirProvider
+        provider: Provider = RirProvider()
+    elif key in {"dbip", "maxmind"}:
+        raise NotImplementedError(
+            f"GeoIP provider {key!r} is not wired yet; only 'rir' ships in MVP."
+        )
+    else:
+        raise ValueError(f"Unsupported GeoIP provider: {key!r}")
+
+    _cached = provider
+    _cached_key = key
+    return provider
+
+
+def reset_cache() -> None:
+    """Forget the singleton — tests swap providers via the env var."""
+    global _cached, _cached_key
+    _cached = None
+    _cached_key = None