fix: make Langflow-synced flows visible (lfx volume perms, pull dedup)

backend/app/flows/export.py

@@ -36,17 +36,45 @@ def flow_path(flows_dir: str | Path, stem: str) -> Path:
     return Path(flows_dir) / f"{stem}.json"
 
 
-def write_flow_file(flows_dir: str | Path, doc: dict, *, name: str | None = None) -> Path:
-    """Write a flow document to backend/flows atomically (tmp + rename).
+def _read_doc(path: Path) -> dict | None:
+    try:
+        doc = json.loads(path.read_text(encoding="utf-8"))
+    except (OSError, ValueError):
+        return None
+    return doc if isinstance(doc, dict) else None
 
-    The filename derives from `name` (or the document's own name). Returns
-    the written path.
+
+def find_reuse_path(flows_dir: str | Path, doc: dict) -> tuple[Path | None, bool]:
+    """Existing file to reuse for `doc`: (path, identical).
+
+    Matches identical content first (any filename), then the same flow name.
+    Returns (None, False) when no candidate exists (caller writes a slug file).
+    This keeps pulls idempotent: a flow seeded from `simple_rule.json` is
+    updated in place instead of duplicated as `simple-rule.json`.
     """
     flows_dir = Path(flows_dir)
-    flows_dir.mkdir(parents=True, exist_ok=True)
-    stem = slugify(name or doc.get("name") or "flow")
-    target = flow_path(flows_dir, stem)
-    fd, tmp_name = tempfile.mkstemp(dir=str(flows_dir), prefix=f".{stem}-", suffix=".tmp")
+    if not flows_dir.is_dir():
+        return None, False
+    wanted_hash = content_hash(doc)
+    wanted_name = doc.get("name")
+    named: Path | None = None
+    for path in iter_flow_files(flows_dir):
+        existing = _read_doc(path)
+        if existing is None:
+            continue
+        if content_hash(existing) == wanted_hash:
+            return path, True
+        if named is None and wanted_name and existing.get("name") == wanted_name:
+            named = path
+    return (named, False) if named is not None else (None, False)
+
+
+def write_flow_bytes(target: Path, doc: dict) -> Path:
+    """Write a flow document to an explicit path atomically (tmp + rename)."""
+    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))
@@ -60,6 +88,18 @@ def write_flow_file(flows_dir: str | Path, doc: dict, *, name: str | None = None
     return target
 
 
+def write_flow_file(flows_dir: str | Path, doc: dict, *, name: str | None = None) -> Path:
+    """Write a flow document to backend/flows atomically (tmp + rename).
+
+    The filename derives from `name` (or the document's own name). Returns
+    the written path.
+    """
+    flows_dir = Path(flows_dir)
+    flows_dir.mkdir(parents=True, exist_ok=True)
+    stem = slugify(name or doc.get("name") or "flow")
+    return write_flow_bytes(flow_path(flows_dir, stem), doc)
+
+
 def iter_flow_files(flows_dir: str | Path) -> list[Path]:
     """Sorted list of candidate flow files (top level only)."""
     return sorted(Path(flows_dir).glob(FLOWS_GLOB))