python - 浏览器中的图像缓存 - app-engine-patch 应用程序

Question

我在为我的应用程序引擎应用程序缓存浏览器中的图像时遇到了一点问题，我正在发送最后修改、过期和缓存控制标头，但每次都从服务器加载图像。这是代码的标题部分：

响应['Content-Type'] = '图片/jpg'

response['Last-Modified'] = current_time.strftime('%a, %d %b %Y %H:%M:%S GMT')

response['Expires'] = current_time + timedelta(days=30)

响应['缓存控制'] = '公共，最大年龄 = 2592000'

Answer 1

这是我在 dpaste 中的修复副本的示例代码

def view_image(request, key):
  data = memcache.get(key)  
  if data is not None:  
    if(request.META.get('HTTP_IF_MODIFIED_SINCE') >= data['Last-Modified']):  
      data.status_code = 304  
    return data  
  else:  
    image_content_blob = #some code to get the image from the data store  
    current_time = datetime.utcnow()
    response = HttpResponse()
    last_modified = current_time - timedelta(days=1)
    response['Content-Type'] = 'image/jpg'
    response['Last-Modified'] = last_modified.strftime('%a, %d %b %Y %H:%M:%S GMT')
    response['Expires'] = current_time + timedelta(days=30)
    response['Cache-Control']  = 'public, max-age=315360000'
    response['Date']           = current_time
    response.content = image_content_blob

    memcache.add(image_key, response, 86400)
    return response