Django rest框架默认值随机标识符
我试图在MongoEngine中保存动态文档时调试一个奇怪的行为。 文档类声明如下:Django rest框架默认值随机标识符,django,django-rest-framework,mongoengine,Django,Django Rest Framework,Mongoengine,我试图在MongoEngine中保存动态文档时调试一个奇怪的行为。 文档类声明如下: class Command(DynamicDocument): meta = { 'collection': 'executor_data_commands' } name = StringField() args = DynamicField() issued_at = LongField(default=time.time()) sync_w
class Command(DynamicDocument):
meta = {
'collection': 'executor_data_commands'
}
name = StringField()
args = DynamicField()
issued_at = LongField(default=time.time())
sync_with_kafka = BooleanField(default=False)
correlation_id = StringField(
default=''.join(random.choice(string.ascii_uppercase + string.digits) for _ in range(10))
)
commands_output = DynamicField(default=None)
@classmethod
def post_save(cls, sender, document, **kwargs):
"""
Send data to Kafka executor data topic after a new instance has been saved
:param sender: the sender who emitted the signal
:param document: the saved instance
"""
if kwargs['created']:
CommandHandler(document).send_command()
class CommandHandler:
"""
Command handler class
"""
def __init__(self, command_instance):
self.command_instance = command_instance
def send_command(self):
"""
Send command to Kafka queue and save the response in the
local database
:return: True if message is published over Kafka channel
False otherwise
"""
headers = {
"Content-Type": "application/vnd.kafka.json.v2+json",
"Accept": "application/vnd.kafka.v2+json"
}
logger_kafka_handlers.info(
"Got new command: %s - %s" % (self.command_instance.name, self.command_instance.args))
args = self.command_instance.args
if 'machine_identifier' in args:
args['machine_identifier'] = MACHINE_MAPPING.get(args['machine_identifier'], args['machine_identifier'])
response = requests.post(
KAFKA_BROKER_EXECUTOR_COMMANDS_IN['host'],
json={"records": [{"value": {
"name": self.command_instance.name,
"args": args,
"correlation_id": self.command_instance.correlation_id,
"issued_ts": time.time()
}}]},
headers=headers,
auth=(KAFKA_BROKER_EXECUTOR_COMMANDS_IN['user'], KAFKA_BROKER_EXECUTOR_COMMANDS_IN['password'])
)
self.command_instance.sync_with_kafka = True if response.status_code == 200 else False
self.command_instance.save()
logger_kafka_handlers.info(
"Handled new command; Name: %s - Args: %s - Sync with Kafka: %s; CorrelationId: %s" % (
self.command_instance.name, self.command_instance.args, self.command_instance.sync_with_kafka,
self.command_instance.correlation_id))
因此,我希望创建的文档将有一个10个字母的随机关联id,并传递给post_save处理程序,该处理程序基本上执行HTTP请求并记录实例字段
该问题与相关id字段相关:
似乎为每个保存的实例指定的默认值等于数据库中保存的另一个实例
我排除了hood update查询以及一些变量重新分配,因为在send_命令方法的最后一行记录实例字段时,问题是显而易见的
想法
谢谢,
FB问题在于您对
默认值的理解
我不确定mongo DynamicDocument,但我假设它的行为与普通模型相同
所以,
从文件中:
字段的默认值。这可以是值,也可以是可调用的
对象如果可调用,则每次调用新对象时都会调用它
创造
在您的情况下,它是不可调用的,因此在创建模型类时只调用一次
您需要使其可调用,因此将实现移动到函数:
def generate_random_corr():
return ''.join(random.choice(string.ascii_uppercase + string.digits) for _ in range(10))
并在模型类中使用它,如下所示:
correlation_id = StringField(default=generate_random_corr)
这同样适用于其他字段:
issued_at = LongField(default=time.time())
所有对象的时间都是一样的。哦,谢谢!我以为有什么棘手的事,但我没想到会发生这样的事!我会让你知道的!谢谢你的提示!