feat: schéma résilient URL→cache + suppression DATA_SCHEMA_LOCAL (#78)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/utils/data.py

@@ -2,7 +2,6 @@ import json
 import logging
 import os
 from collections import OrderedDict
-from pathlib import Path
 
 import httpx
 import polars as pl
@@ -65,34 +64,57 @@ def get_departement_region(code_postal: str | None):
     return "", "", ""
 
 
+def _validate_schema(raw) -> dict | None:
+    if isinstance(raw, dict) and isinstance(raw.get("fields"), list) and raw["fields"]:
+        return raw
+    return None
+
+
+def _fetch_remote_schema(url: str | None) -> dict | None:
+    if not url:
+        return None
+    try:
+        raw = get(url, follow_redirects=True).raise_for_status().json()
+    except (httpx.HTTPError, json.JSONDecodeError) as e:
+        logger.error(f"Schéma distant indisponible ({url}) : {e}")
+        return None
+    return _validate_schema(raw)
+
+
+def _load_schema_file(path: str) -> dict | None:
+    if not path or not os.path.exists(path):
+        return None
+    try:
+        with open(path) as f:
+            raw = json.load(f)
+    except (OSError, json.JSONDecodeError) as e:
+        logger.error(f"Schéma local illisible ({path}) : {e}")
+        return None
+    return _validate_schema(raw)
+
+
+def _persist_schema_cache(raw: dict, path: str) -> None:
+    if not path:
+        return
+    try:
+        tmp = f"{path}.tmp"
+        with open(tmp, "w") as f:
+            json.dump(raw, f)
+        os.replace(tmp, path)
+    except OSError as e:
+        logger.warning(f"Écriture du cache schéma échouée ({path}) : {e}")
+
+
 def get_data_schema() -> dict:
-    # Récupération du schéma des données tabulaires
-    url = os.getenv("DATA_SCHEMA_PATH")
-    local_path = Path(os.getenv("DATA_SCHEMA_LOCAL", ""))
-
-    original_schema = {}
-    if url:
-        try:
-            original_schema: dict = get(url, follow_redirects=True).json()
-        except (
-            httpx.ReadTimeout,
-            httpx.ReadError,
-            httpx.ConnectError,
-            httpx.ConnectTimeout,
-        ):
-            logger.error(f"Erreur HTTP lors de la récupération du schéma ({url})")
-
-    if os.path.exists(local_path) and original_schema == {}:
-        with open(local_path) as f:
-            original_schema: dict = json.load(f)
-        logger.info(f"Utilisation du schéma local ({local_path})")
-
-    new_schema = OrderedDict()
-
-    for col in original_schema["fields"]:
-        new_schema[col["name"]] = col
-
-    return new_schema
+    cache_path = os.getenv("DATA_SCHEMA_CACHE", "./schema.cache.json")
+    raw = _fetch_remote_schema(os.getenv("DATA_SCHEMA_PATH"))
+    if raw is not None:
+        _persist_schema_cache(raw, cache_path)
+    else:
+        raw = _load_schema_file(cache_path)
+    if raw is None:
+        raise RuntimeError("Aucun schéma disponible (ni distant ni cache).")
+    return OrderedDict((c["name"], c) for c in raw["fields"])
 
 
 def prepare_dashboard_data(**filter_params) -> pl.DataFrame: