refactor: form-core wiring, JWT sessions, slowapi, packaging, frontend rewrite, test declutter

backend/app/flows/export.py

@@ -10,7 +10,6 @@ import hashlib
 import json
 import os
 import re
-import tempfile
 from pathlib import Path
 
 FLOWS_GLOB = "*.json"
@@ -20,18 +19,32 @@ FLOWS_GLOB = "*.json"
 #: validated, or shown in the frontend.
 IGNORE_FILENAME = ".flowsignore"
 
+# mtime-keyed cache: the watcher re-reads per event, the file rarely changes.
+_ignore_cache: dict[str, tuple[float, set[str]]] = {}
+
 
 def ignored_stems(flows_dir: str | Path) -> set[str]:
     """Stems excluded from the pipeline (empty when no ignore file)."""
+    key = str(Path(flows_dir))
+    try:
+        mtime = (Path(flows_dir) / IGNORE_FILENAME).stat().st_mtime
+    except OSError:
+        _ignore_cache.pop(key, None)
+        return set()
+    cached = _ignore_cache.get(key)
+    if cached is not None and cached[0] == mtime:
+        return cached[1]
     try:
         text = (Path(flows_dir) / IGNORE_FILENAME).read_text(encoding="utf-8")
     except OSError:
         return set()
-    return {
+    stems = {
         line.strip()
         for line in text.splitlines()
         if line.strip() and not line.strip().startswith("#")
     }
+    _ignore_cache[key] = (mtime, stems)
+    return stems
 
 
 def filename_stem(name: str) -> str:
@@ -97,25 +110,16 @@ def find_reuse_path(flows_dir: str | Path, doc: dict) -> tuple[Path | None, bool
 def write_flow_bytes(target: Path, doc: dict) -> Path:
     """Write a flow document to an explicit path atomically (tmp + rename).
 
-    The file ends up world-readable (0o644): mkstemp creates 0o600, which
-    would lock out the other containers (Langflow/LFX run as different
-    users and crash on unreadable seed files).
+    The file ends up world-readable (0o644): atomicwrites follows the
+    umask, which would lock out the other containers (Langflow/LFX run
+    as different users and crash on unreadable seed files).
     """
+    from atomicwrites import atomic_write
+
     target.parent.mkdir(parents=True, exist_ok=True)
-    fd, tmp_name = tempfile.mkstemp(
-        dir=str(target.parent), prefix=f".{target.stem}-", suffix=".tmp"
-    )
-    try:
-        with os.fdopen(fd, "wb") as tmp:
-            tmp.write(canonical_bytes(doc))
-        os.replace(tmp_name, target)
-        os.chmod(target, 0o644)
-    except BaseException:
-        try:
-            os.unlink(tmp_name)
-        except OSError:
-            pass
-        raise
+    with atomic_write(target, mode="wb", overwrite=True) as tmp:
+        tmp.write(canonical_bytes(doc))
+    os.chmod(target, 0o644)
     return target