python - (distutil + shutil) * 复制树 =?

Question

我想要 shutil 的 copytree 函数提供的忽略模式。我希望 src 树替换 dest 目录中的所有现有文件/文件夹，如 distutil.dir_util.copy_tree。

我是一个相当新的 Python 用户，似乎找不到任何关于此的帖子。

Answer 1

我早就想说这个了，但我没有说。 http://docs.python.org/library/shutil.html有一个版本的copytree函数。我查看了它是否会替换现有文件，据我所知，它会覆盖现有文件，但如果任何目录已经存在，它就会失败。由于 os.mkdirs 如果目录已经存在则失败。

所需的导入:

import os
import os.path
import shutil

从 http://code.activestate.com/recipes/82465-a-friendly-mkdir/ 获取 _mkdir (那里的一位评论者提到 os.mkdirs 具有大部分相同的行为，但没有注意到 _mkdir 如果已经创建任何目录则不会失败存在)

def _mkdir(newdir):
    """works the way a good mkdir should :)
        - already exists, silently complete
        - regular file in the way, raise an exception
        - parent directory(ies) does not exist, make them as well
    """
    if os.path.isdir(newdir):
        pass
    elif os.path.isfile(newdir):
        raise OSError("a file with the same name as the desired " \
                      "dir, '%s', already exists." % newdir)
    else:
        head, tail = os.path.split(newdir)
        if head and not os.path.isdir(head):
            _mkdir(head)
        #print "_mkdir %s" % repr(newdir)
        if tail:
            os.mkdir(newdir)

尽管它不像 os.mkdirs 那样采用 mode 参数，但 copytree 不使用它，因此不需要它.

然后更改 copytree 以调用 _mkdir 而不是 os.mkdirs:

def copytree(src, dst, symlinks=False):
    """Recursively copy a directory tree using copy2().

    The destination directory must not already exist.
    If exception(s) occur, an Error is raised with a list of reasons.

    If the optional symlinks flag is true, symbolic links in the
    source tree result in symbolic links in the destination tree; if
    it is false, the contents of the files pointed to by symbolic
    links are copied.

    XXX Consider this example code rather than the ultimate tool.

    """
    names = os.listdir(src)
    # os.makedirs(dst)
    _mkdir(dst) # XXX
    errors = []
    for name in names:
        srcname = os.path.join(src, name)
        dstname = os.path.join(dst, name)
        try:
            if symlinks and os.path.islink(srcname):
                linkto = os.readlink(srcname)
                os.symlink(linkto, dstname)
            elif os.path.isdir(srcname):
                copytree(srcname, dstname, symlinks)
            else:
                shutil.copy2(srcname, dstname)
            # XXX What about devices, sockets etc.?
        except (IOError, os.error), why:
            errors.append((srcname, dstname, str(why)))
        # catch the Error from the recursive copytree so that we can
        # continue with other files
        except Error, err:
            errors.extend(err.args[0])
    try:
        shutil.copystat(src, dst)
    except WindowsError:
        # can't copy file access times on Windows
        pass