Create nltk_bootstrap.py

utils/nltk_bootstrap.py

@@ -0,0 +1,39 @@
+# app/utils/nltk_bootstrap.py
+import os
+import pathlib
+
+def ensure_punkt():
+    """
+    Make NLTK look in a writable dir, download 'punkt_tab' (or 'punkt')
+    if missing, and inject that dir into nltk.data.path. No-op if already present.
+    """
+    try:
+        import nltk  # import here so module is optional at build time
+    except Exception:
+        return  # If NLTK isn't installed, caller should have a fallback
+
+    # Choose a persistent/writable location
+    base = "/data/nltk_data" if os.path.isdir("/data") else os.path.join(os.path.dirname(__file__), "..", "nltk_data")
+    nltd = os.path.abspath(base)
+    os.makedirs(nltd, exist_ok=True)
+
+    # Environment + explicit path injection (important in Spaces)
+    os.environ["NLTK_DATA"] = nltd
+    if nltd not in nltk.data.path:
+        nltk.data.path.insert(0, nltd)
+
+    # Try new resource first, then the legacy one
+    for res in ("punkt_tab", "punkt"):
+        try:
+            nltk.data.find(f"tokenizers/{res}")
+            return
+        except LookupError:
+            try:
+                nltk.download(res, download_dir=nltd, quiet=True, raise_on_error=True)
+                # After download, ensure it's on the path and return
+                if nltd not in nltk.data.path:
+                    nltk.data.path.insert(0, nltd)
+                return
+            except Exception:
+                # Try the next resource name
+                continue