临时文件、目录

创建临时文件和目录

官方文档

Python提供了 tempfile 模块来便捷的创建临时文件和目录。

• tempfile 可以在你程序运行时打开并存储临时的数据在文件或目录中。
• tempfile 会在你程序停止运行后删除这些临时文件。

临时文件

from tempfile import  TemporaryFile

# 创建一个临时文件并为其写入一些数据
fp = TemporaryFile('w+t')
fp.write('Hello World!')

# 回到开始，从文件中读取数据
fp.seek(0)
data = fp.read()
print(data)

# 关闭文件，之后他将会被删除
fp.close()

# 临时文件现在已经被关闭和删除
with TemporaryFile('w+t') as fp:
    fp.write('Hello universe!')
    fp.seek(0)
    fp.read()

这将创建一个临时文件并从中读取数据。 一旦读取文件的内容，就会关闭临时文件并从文件系统中删除。

tempfile 也可用于创建临时目录。

临时目录

import tempfile
import os

tmp = ''
with tempfile.TemporaryDirectory(
    dir=r"W:\CPS\MyProject\python-tools\gis-api\static\upload", # 如果不指定dir，则在系统默认的临时目录创建
    prefix="mikeio_", # 前缀
    suffix=None, # 后缀
) as tmpdir:
    print('Created temporary directory ', tmpdir)
    tmp = tmpdir
    print(os.path.exists(tmpdir))

print(tmp)
print(os.path.exists(tmp))

调用 tempfile.TemporaryDirectory() 会在文件系统中创建一个临时目录，并返回一个表示该目录的对象。

在上面的示例中，使用上下文管理器创建目录，目录的名称存储在 tmpdir 变量中。

第三行打印出临时目录的名称，os.path.exists(tmpdir) 来确认目录是否实际在文件系统中创建。 在上下文管理器退出上下文后，临时目录将被删除，并且对 os.path.exists(tmpdir)的调用将返回False，这意味着该目录已成功删除。

使用示例

python2.7

代码来自网络，在gis-api项目中用于调用arcpy模块使用过，没有什么大问题

from tempfile import mkdtemp

class TemporaryDirectory(object):
    """Create and return a temporary directory.  This has the same
    behavior as mkdtemp but can be used as a context manager.  For
    example:

        with TemporaryDirectory() as tmpdir:
            ...

    Upon exiting the context, the directory and everything contained
    in it are removed.
    """

    def __init__(self, suffix="", prefix="tmp", dir=None):
        self._closed = False
        self.name = None  # Handle mkdtemp raising an exception
        self.name = mkdtemp(suffix, prefix, dir)

    def __repr__(self):
        return "<{} {!r}>".format(self.__class__.__name__, self.name)

    def __enter__(self):
        return self.name

    def cleanup(self, _warn=False):
        if self.name and not self._closed:
            try:
                self._rmtree(self.name)
            except (TypeError, AttributeError) as ex:
                # Issue #10188: Emit a warning on stderr
                # if the directory could not be cleaned
                # up due to missing globals
                if "None" not in str(ex):
                    raise
                print(
                    "ERROR: {!r} while cleaning up {!r}".format(
                        ex,
                        self,
                    )
                )
                return
            self._closed = True
            if _warn:
                self._warn("Implicitly cleaning up {!r}".format(self), ResourceWarning)

    def __exit__(self, exc, value, tb):
        self.cleanup()

    def __del__(self):
        # Issue a ResourceWarning if implicit cleanup needed
        self.cleanup(_warn=True)

    # XXX (ncoghlan): The following code attempts to make
    # this class tolerant of the module nulling out process
    # that happens during CPython interpreter shutdown
    # Alas, it doesn't actually manage it. See issue #10188
    _listdir = staticmethod(os.listdir)
    _path_join = staticmethod(os.path.join)
    _isdir = staticmethod(os.path.isdir)
    _islink = staticmethod(os.path.islink)
    _remove = staticmethod(os.remove)
    _rmdir = staticmethod(os.rmdir)
    _warn = _warnings.warn

    def _rmtree(self, path):
        # Essentially a stripped down version of shutil.rmtree.  We can't
        # use globals because they may be None'ed out at shutdown.
        for name in self._listdir(path):
            fullname = self._path_join(path, name)
            try:
                isdir = self._isdir(fullname) and not self._islink(fullname)
            except OSError:
                isdir = False
            if isdir:
                self._rmtree(fullname)
            else:
                try:
                    self._remove(fullname)
                except OSError:
                    pass
        try:
            self._rmdir(path)
        except OSError:
            pass

使用

def main():
    with TemporaryDirectory() as tmp_dir:
        if not os.path.isdir(tmp_dir):
            raise "Temporary directory can't not used"
        else:
            print("Work in Temporary directory path: %s" % tmp_dir)