访问路由，读取本地图片文件并返回

web_img.py

import os
from flask make_response

file_path = os.path.join(os.getcwd(), 'app/templates/email/shadow_img.png')
img_content = 'image/png'
log_debug(file_path)
img = open(file_path).read()
response = make_response(img)
response.headers['Content-Type'] = img_content
return response