Django2.0 ImageField 和FileField上

Django开发中经常会遇到上传文件后改名，以避免文件重名

其中上传文件后需要处理中文文件名或者重名，比较麻烦upload_to 可以设置成 upload_to="images/%Y/%m/%d"

也可通过编程动态设置(Django 2.2， Python3.7):

from uuid import uuid4
from datetime import datetime

def upload_article_cover(instance,filename): 
    ext = filename.split('.')[-1] #日期目录和 随机文件名 
    filename = f'{uuid4().hex}.{ext}'
    
    now = datetime.now()
    year,month,day = now.year ,now.month ,now.day 
    
    # instance可使用instance.user.id 
    return f"article/cover/{year}/{month}/{day}/{filename}"

class Article(models.Model): 
    width= models.IntegerField(null=True, blank=True) 
    height= models.IntegerField(null=True, blank=True)
    cover = models.ImageField(upload_to=upload_article_cover, default="article/cover/default.png", width_field="width", height_field="height" )