python - 如何更新未知状态的深度嵌套字典？

Question

我有 3 级深度的字典。我不知道 key 是否存在。如果它们存在，我需要更新该值。如果它们不存在，我需要添加键和值。

这是我的代码...但很困惑。必须有一种更干净、更优雅的方法来做到这一点？？？

建议？？？

def update_balances_cache(client_name, exchange_name,
                      api_key_nickname, balances,
                      time_checked):

from settings import CACHE

'''
Dictionary structure:
balances = {client_name: {exchange_name: {api_key_nickname: {balances}
                                        }
                             }
               }

CACHE is a class instance holding shared variables between modules.

'''

api_key_level = {api_key_nickname: balances}

exchange_level = {exchange_name: api_key_level}


with CACHE.vlock:
    try:
        # is there a client in the dictionary?
        CACHE.BALANCES_CACHE[client_name]
    except:
        # add client level to dictionary
        CACHE.BALANCES_CACHE[client_name] = exchange_level
        CACHE.BALANCES_CACHE[client_name][exchange_name][api_key_nickname]['last check time'] = time_checked

        return

    # there is a client in the dictionary.  Is the exchange there?
    try:
        CACHE.BALANCES_CACHE[client_name][exchange_name]
    except:
        # add the exchange
        CACHE.BALANCES_CACHE[client_name][exchange_name] = exchange_level
        CACHE.BALANCES_CACHE[client_name][exchange_name][api_key_nickname]['last check time'] = time_checked

        return

    # there is a client & exchange.
    CACHE.BALANCES_CACHE[client_name][exchange_name][api_key_nickname] = api_key_level
    CACHE.BALANCES_CACHE[client_name][exchange_name][api_key_nickname]['last check time'] = time_checked

return

Answer 1

试试这个

def updatedict(a,b):
  for key in b:
      if not key in a or type(a[key]) != dict or type(b[key])!=dict:
          a[key]=b[key]
      else:
          updatedict(a[key],b[key])
x={"a":{"b":{"c":"d"}}}
y={"a":{"b":{"e":"f","c":"d1"},"g":{"h":"i"}},"j":{"k":{"l":"m"}}}
updatedict(x,y)
print(x)

更新后的 x 值

{'j': {'k': {'l': 'm'}}, 'a': {'b': {'c': 'd1', 'e': 'f'}, 'g': {'h': 'i'}}}