小编Mik*_*son的帖子

我有MyModel领域field1和模型field2。我想要这两个字段之一。我怎样才能做到这一点？

class MyModel(models.Model):
    field1 = models.TextField(?)
    field2 = models.TextField(?)

我正在寻找一种我已看到但被遗忘的特定，最佳实践的方法，而不是最重要的clean函数方法。我确实记得该方法覆盖了某些功能，但是我认为它不是clean。

提前致谢

例如,让我们说:

$startIndex = 21; 
$totalItems = 100;
$itemsPerPage = 10;
$totalPages = ceil($totalItems / $itemsPerPage);  // (10)

$currentpage = //I am stumped here.

$ currentpage是什么,基于$ startIndex？

我正在进行分页,它正在踢我的屁股.我知道这可能是一些非常简单的数学,但我现在想不到.

我正在关注本教程:https://gearheart.io/blog/creating-a-chat-with-django-channels/

我在运行manage.py runserver时遇到以下代码时出现此错误

#settings.py

redis_host = os.environ.get('REDIS_HOST', 'localhost')

# Channel layer definitions
# http://channels.readthedocs.org/en/latest/deploying.html#setting-up-a-channel-backend
CHANNEL_LAYERS = {
    "default": {
        # This example app uses the Redis channel layer implementation asgi_redis
        "BACKEND": "asgi_redis.RedisChannelLayer",
        "CONFIG": {
            "hosts": [(redis_host, 6379)],
        },
       "ROUTING": "gameapollius.routing.channel_routing", # We will create it in a moment
    },
}

#routing.py

from channels import route,include

def message_handler(message):
    print(message['text'])

channel_routing = [
    route('websocket.receive', message_handler)
]

#traceback

In [1]: import websocket

In [2]: ws = websocket.WebSocket()

In [3]: ws.connect("ws://localhost:8000") …

我有一个Django应用，用户可以使用它使用多个视频创建视频拼贴。问题是，在生产中，将视频上传到Amazon s3时，我遇到了502错误的网关（在本地工作正常）。有谁知道可能是错的吗？我已经设定

client_max_body_size 100M

和

fastcgi_buffers 8 16k;
fastcgi_buffer_size 32k;
fastcgi_connect_timeout 3000;
fastcgi_send_timeout 3000;
fastcgi_read_timeout 3000;

有谁知道可能是错的吗？提前致谢

完整错误：

2017/12/31 23:50:51 [error] 1279#1279: *1 upstream prematurely closed connection while reading response header from upstream, 
client: 107.205.110.154, 
server: movingcollage.com, 
request: "POST /create-collage/ HTTP/1.1", 
upstream: "http://unix:/home/mike/movingcollage/movingcollage.sock:/create-collage/", 
host: "movingcollage.com", referrer: "http://movingcollage.com/create-collage/"

serializers.py

from django.contrib.auth.models import User
from engine.models import Game
from rest_framework import serializers

class GameSerializer(serializers.ModelSerializer):
    class Meta:
        model = Game
        fields = (
            'game_name',
            'level',
            'game_type',
            'creator',
            'id',
        )

我想creator.username为creator刚刚返回用户对象，它是创作者的ID的整数。如何获取creator.username而不是creator？