有什么方法可以让我在蜘蛛中拥有持久的请求元数据？request.meta只持续到下一个回调，我必须做这样的事情：
def method1(self, response):
request = Request(url, callback=self.method2)
request.meta['persist'] = ...
yield request
def method2(self, response):
...
request = Request(url, callback=self.method3)
request.meta['persist'] = response.meta['persist']
yield request
我也做了一个装饰器，但我真的希望有一个更清洁的解决方案：
def persist_meta(callback):
def inner(self, *args, **kwargs):
for result in callback(self, *args, **kwargs):
if isinstance(result, Request):
response = args[0]
persist = response.meta.get('persist', {})
persist.update(result.meta.get('persist', {})
result.meta['persist'] = persist
yield result
return inner
任何帮助表示赞赏。