Launcher: ensure repo-local HF/transformers cache directories are created and writable

streamlit_app.py

@@ -3,6 +3,7 @@
 Launcher for Hugging Face Spaces / Streamlit:
  - force XDG_CONFIG_HOME/HOME to a writable folder in the repo
  - create a minimal .streamlit/config.toml if missing
+ - ensure Hugging Face / transformers cache dirs are repo-local and writable
  - add repo/src to sys.path so `from data_loader import ...` works
  - run the actual app (src/app.py) as __main__
 """
@@ -10,18 +11,33 @@ import os
 from pathlib import Path
 import runpy
 import sys
+import stat
 
 ROOT = Path(__file__).parent.resolve()
 STREAMLIT_DIR = ROOT.joinpath(".streamlit")
 
 # --- FORCE environment variables (overwrite any existing HF defaults) ---
-# Use a repo-local .streamlit directory so Streamlit won't try to write to '/'
 os.environ["XDG_CONFIG_HOME"] = str(STREAMLIT_DIR)
 # Ensure HOME is a writable folder inside the repo as well
 os.environ["HOME"] = str(ROOT)
 # Also set STREAMLIT_RUNTIME_DIR (added safety)
 os.environ.setdefault("STREAMLIT_RUNTIME_DIR", str(ROOT.joinpath(".streamlit", "runtime")))
 
+# --- Setup repository-local cache for huggingface / transformers ---
+# Put all caches under repo .cache so the process can create and write to them
+CACHE_ROOT = ROOT.joinpath(".cache")
+TF_CACHE = CACHE_ROOT.joinpath("transformers")
+HF_HOME = CACHE_ROOT.joinpath("huggingface")
+DATASETS_CACHE = CACHE_ROOT.joinpath("datasets")
+
+# Set env vars used by HF libs
+os.environ.setdefault("XDG_CACHE_HOME", str(CACHE_ROOT))
+os.environ.setdefault("TRANSFORMERS_CACHE", str(TF_CACHE))
+os.environ.setdefault("HF_HOME", str(HF_HOME))
+os.environ.setdefault("HF_DATASETS_CACHE", str(DATASETS_CACHE))
+# Optional: also set general cache-related vars
+os.environ.setdefault("HF_METRICS_CACHE", str(CACHE_ROOT.joinpath("metrics")))
+
 # 2) Create .streamlit and a minimal config.toml if it doesn't exist
 STREAMLIT_DIR.mkdir(parents=True, exist_ok=True)
 cfg = STREAMLIT_DIR.joinpath("config.toml")
@@ -41,6 +57,16 @@ if not cfg.exists():
 runtime_dir = Path(os.environ.get("STREAMLIT_RUNTIME_DIR"))
 runtime_dir.mkdir(parents=True, exist_ok=True)
 
+# Make sure cache dirs exist and are world-writable (so HF download locks work)
+for d in (CACHE_ROOT, TF_CACHE, HF_HOME, DATASETS_CACHE, runtime_dir):
+    try:
+        d.mkdir(parents=True, exist_ok=True)
+        # chmod 0o777 so non-root runtime user can create lock files & write
+        d.chmod(0o777)
+    except Exception:
+        # best-effort; continue (we will show diagnostics below)
+        pass
+
 # --- ADD src directory to Python import path so app can import modules by name ---
 SRC_DIR = str(ROOT.joinpath("src"))
 if SRC_DIR not in sys.path:
@@ -51,7 +77,17 @@ if SRC_DIR not in sys.path:
 print("streamlit_app launcher: XDG_CONFIG_HOME =", os.environ.get("XDG_CONFIG_HOME"))
 print("streamlit_app launcher: HOME =", os.environ.get("HOME"))
 print("streamlit_app launcher: STREAMLIT_RUNTIME_DIR =", os.environ.get("STREAMLIT_RUNTIME_DIR"))
+print("streamlit_app launcher: XDG_CACHE_HOME =", os.environ.get("XDG_CACHE_HOME"))
+print("streamlit_app launcher: TRANSFORMERS_CACHE =", os.environ.get("TRANSFORMERS_CACHE"))
+print("streamlit_app launcher: HF_HOME =", os.environ.get("HF_HOME"))
+print("streamlit_app launcher: HF_DATASETS_CACHE =", os.environ.get("HF_DATASETS_CACHE"))
 print("streamlit_app launcher: sys.path[0] =", sys.path[0])
+# show permission bits for the main cache dir
+try:
+    st = CACHE_ROOT.stat()
+    print("streamlit_app launcher: .cache exists, mode:", oct(st.st_mode & 0o777))
+except Exception:
+    print("streamlit_app launcher: .cache stat failed or missing")
 sys.stdout.flush()
 
 # 4) Run your real Streamlit app script (runs as __main__)