FileSystem API¶

The FileSystem class provides low-level access to the content-addressable DAG.

Constructor¶

from dagshell.dagshell import FileSystem

fs = FileSystem()

Basic Operations¶

read(path) -> Optional[bytes]¶

Read file contents.

content = fs.read("/etc/passwd")
if content:
    text = content.decode('utf-8')

write(path, content) -> bool¶

Write content to file.

fs.write("/file.txt", b"Hello World")
fs.write("/file.txt", "Text content".encode())

exists(path) -> bool¶

Check if path exists.

if fs.exists("/path/to/file"):
    content = fs.read("/path/to/file")

stat(path) -> Optional[Dict]¶

Get file information.

info = fs.stat("/file.txt")
# Returns:
# {
#     'type': 'file',
#     'size': 1234,
#     'mode': 0o644,
#     'uid': 1000,
#     'gid': 1000,
#     'mtime': 1234567890.0
# }

ls(path) -> Optional[List[str]]¶

List directory contents.

entries = fs.ls("/home")
# Returns: ['user1', 'user2', ...]

Directory Operations¶

mkdir(path) -> bool¶

Create directory.

fs.mkdir("/newdir")

rmdir(path) -> bool¶

Remove empty directory.

fs.rmdir("/emptydir")

File Management¶

unlink(path) -> bool¶

Remove file.

fs.unlink("/file.txt")

rename(old, new) -> bool¶

Rename/move file.

fs.rename("/old.txt", "/new.txt")

Links¶

symlink(target, path) -> bool¶

Create symbolic link.

fs.symlink("/target", "/link")

readlink(path) -> Optional[str]¶

Read symbolic link target.

target = fs.readlink("/link")

Permissions¶

chmod(path, mode) -> bool¶

Change file mode.

fs.chmod("/file.txt", 0o755)

chown(path, uid, gid) -> bool¶

Change ownership.

fs.chown("/file.txt", 1000, 1000)

can_read(path, uid, gid) -> bool¶

can_write(path, uid, gid) -> bool¶

can_execute(path, uid, gid) -> bool¶

Check permissions.

if fs.can_write("/file.txt", 1000, 1000):
    fs.write("/file.txt", b"content")

Serialization¶

to_json() -> str¶

Serialize filesystem to JSON.

json_data = fs.to_json()
with open("backup.json", "w") as f:
    f.write(json_data)

from_json(json_str) -> FileSystem¶

Load filesystem from JSON.

with open("backup.json") as f:
    json_data = f.read()
fs = FileSystem.from_json(json_data)

Node Access¶

get_node(hash) -> Optional[Node]¶

Get node by hash.

node = fs.get_node("abc123...")
if isinstance(node, FileNode):
    print(node.content)

Node Types¶

from dagshell.dagshell import FileNode, DirNode, SymlinkNode, DeviceNode

# Check node type
node = fs.get_node(hash)
if node.is_file():
    print(node.content)
elif node.is_dir():
    print(node.entries)
elif node.is_symlink():
    print(node.target)

Constants¶

from dagshell.dagshell import Mode

Mode.IRWXU  # 0o700 - Owner rwx
Mode.IRWXG  # 0o070 - Group rwx
Mode.IRWXO  # 0o007 - Other rwx
Mode.IRUSR  # 0o400 - Owner read
Mode.IWUSR  # 0o200 - Owner write
Mode.IXUSR  # 0o100 - Owner execute
# ... etc