Django:输入图像文件的小写文件名

Question

我有一个模型:

class Foo(models.Model):
    poster = models.ImageField(u"Poster", upload_to='img')

我正在使用管理员上传海报并保存 Foo 对象。我现在需要找到一种在保存前将文件名小写的方法。例如 POSTER.png 或 Poster.png 或 poster.PNG 应小写为 poster.png。

实现此目标的最简单方法是什么？

Answer 1

FileField.upload_to根据文档中的这条评论，也可能是可调用的:

This may also be a callable, such as a function, which will be called to obtain the upload path, including the filename. This callable must be able to accept two arguments, and return a Unix-style path (with forward slashes) to be passed along to the storage system. The two arguments that will be passed are:

自 ImageField从 FileField 继承它的所有属性和方法，我想你可以使用:

def update_filename(instance, filename):
    path_you_want_to_upload_to = "img"
    return os.path.join(path_you_want_to_upload_to, filename.lower())

class Foo(models.Model):
    poster = models.ImageField(u"Poster", upload_to=update_filename)