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

decnet/geoip/rir/parse.py

@@ -0,0 +1,70 @@
+"""Parser for RIR ``delegated-*-extended`` files.
+
+Line shape (the bits we care about)::
+
+    ripencc|DE|ipv4|85.214.0.0|65536|20060814|allocated|<opaque-id>
+
+Fields: registry, country, type (ipv4/ipv6/asn), start, count, date,
+status, id. We emit one ``(start_int, end_int_inclusive, country)``
+tuple per ``ipv4|<cc>|...|allocated|assigned`` row.
+
+Rows skipped:
+
+* ``ipv6`` and ``asn`` types — IPv6 is out of MVP scope, ASN is a
+  different table.
+* ``summary`` / ``version`` header lines (registry|*|*|*|*|summary).
+* Rows with status ``reserved`` / ``available`` — no country assigned.
+* Rows with country ``*`` or ``ZZ`` — sentinel for unassigned space.
+* Rows where count is not a valid power-of-two-ish positive integer
+  (the RIR files are usually tidy, but defensive).
+"""
+from __future__ import annotations
+
+import ipaddress
+import logging
+from pathlib import Path
+from typing import Iterator, Tuple
+
+Range = Tuple[int, int, str]
+
+logger = logging.getLogger("decnet.geoip.rir.parse")
+
+_VALID_STATUSES = frozenset({"allocated", "assigned"})
+_SENTINEL_CCS = frozenset({"*", "ZZ", ""})
+
+
+def parse_file(path: Path) -> Iterator[Range]:
+    """Yield ``(start_int, end_int_inclusive, cc)`` for every ipv4 row."""
+    with path.open("r", encoding="utf-8", errors="replace") as fh:
+        for lineno, raw in enumerate(fh, 1):
+            line = raw.strip()
+            if not line or line.startswith("#"):
+                continue
+            parts = line.split("|")
+            if len(parts) < 7:
+                continue
+            _registry, cc, rtype, start, count, _date, status = parts[:7]
+
+            if rtype != "ipv4":
+                continue
+            if status not in _VALID_STATUSES:
+                continue
+            if cc in _SENTINEL_CCS:
+                continue
+            # summary header carries type=ipv4 but start=='*' and status
+                # =='summary' — already filtered by _VALID_STATUSES, but
+                # keep the guard for defensiveness.
+            if start in ("*", ""):
+                continue
+
+            try:
+                start_int = int(ipaddress.IPv4Address(start))
+                n = int(count)
+            except (ValueError, ipaddress.AddressValueError):
+                logger.debug("geoip.rir: skipping malformed line %d in %s", lineno, path.name)
+                continue
+            if n <= 0:
+                continue
+
+            end_int = start_int + n - 1
+            yield (start_int, end_int, cc.upper())