1 files changed, 45 insertions, 0 deletions
diff --git a/pkgs/by-name/ni/nix-required-mounts/scripts/nix_required_mounts_closure.py b/pkgs/by-name/ni/nix-required-mounts/scripts/nix_required_mounts_closure.py
new file mode 100644
index 0000000000000..4425e98d09251
--- /dev/null
+++ b/pkgs/by-name/ni/nix-required-mounts/scripts/nix_required_mounts_closure.py
@@ -0,0 +1,45 @@
+import json
+import os
+
+store_dir = os.environ["storeDir"]
+
+with open(os.environ["shallowConfigPath"], "r") as f:
+    config = json.load(f)
+
+cache = {}
+
+
+def read_edges(path: str | dict) -> list[str | dict]:
+    if isinstance(path, dict):
+        return [path]
+    assert isinstance(path, str)
+
+    if not path.startswith(store_dir):
+        return [path]
+    if path in cache:
+        return cache[path]
+
+    name = f"references-{path.removeprefix(store_dir)}"
+
+    assert os.path.exists(name)
+
+    with open(name, "r") as f:
+        return [p.strip() for p in f.readlines() if p.startswith(store_dir)]
+
+
+def host_path(mount: str | dict) -> str:
+    if isinstance(mount, dict):
+        return mount["host"]
+    assert isinstance(mount, str), mount
+    return mount
+
+
+for pattern in config:
+    closure = []
+    for path in config[pattern]["paths"]:
+        closure.append(path)
+        closure.extend(read_edges(path))
+    config[pattern]["paths"] = list({host_path(m): m for m in closure}.values())
+
+with open(os.environ["out"], "w") as f:
+    json.dump(config, f)