grocery-manager/app/rest/save.py

#
# Copyright (c) Daniel Sheffield 2023
# All rights reserved
#
# THIS SOFTWARE IS PROVIDED AS IS WITHOUT WARRANTY

from hashlib import blake2b
from io import BufferedRandom
import os
from uuid import uuid4
from .hash_util import DIGEST_SIZE_BYTES, blake, bytes_to_base32


def save(content: bytes, root='app/rest/static') -> str:
    _bytes = blake(content, person='clip'.encode('utf-8'))
    _b32 = bytes_to_base32(_bytes)
    directory = f'{root}/{_b32}'
    try:
        os.mkdir(directory, mode=0o700, dir_fd=None)
    except FileExistsError:
        pass
    fd = os.open(f'{directory}/{_b32}.file', os.O_WRONLY | os.O_TRUNC | os.O_CREAT, 0o600)
    with open(fd, "wb") as f:
        f.write(content)
    return _b32

def save_upload(content: BufferedRandom, root='app/rest/static') -> str:
    tmpdir = '/tmp/upload'
    try:
        os.mkdir(tmpdir, mode=0o700, dir_fd=None)
    except FileExistsError:
        pass
    unique = uuid4()
    fd = os.open(f'{tmpdir}/{unique.hex}', os.O_WRONLY | os.O_TRUNC | os.O_CREAT, 0o600)
    with open(fd, "wb") as f:
        while content.peek(1):
            seg = content.read(1024)
            f.write(seg)
    
    fd = os.open(f'{tmpdir}/{unique.hex}', os.O_RDONLY, 0o600)
    with open(fd, "rb") as f:
        f.seek(0)
        _blake = blake2b(usedforsecurity=False, digest_size=DIGEST_SIZE_BYTES, person='upload'.encode('utf-8'))
        while f.peek(1):
            _blake.update(f.read(1024))
        
        _bytes = _blake.digest()
        _b32 = bytes_to_base32(_bytes)
    
    directory = f'{root}/{_b32}'
    try:
        os.mkdir(directory, mode=0o700, dir_fd=None)
    except FileExistsError:
        pass

    os.replace(f'{tmpdir}/{unique.hex}', f'{directory}/{_b32}.file')
    
    return _b32