过滤JSON输出

Question

我想过滤一个JSON输出，但是它给了我以下错误：

File "main.py", line 40, in on_ready
output_dict = [x for x in a2 if x['type'] == 'ORDER_FILL']
File "main.py", line 40, in <listcomp>
output_dict = [x for x in a2 if x['type'] == 'ORDER_FILL']
TypeError: string indices must be integers

这是我的密码：

json_output = {'transactions': [{'id': '111', 'accountID': 'xxxxx', 'userID': xxxxx, 'batchID': '109', 'time': '2022-01-31T00:50:29.592777450Z', 'type': 'STOP_LOSS_ORDER', 'tradeID': '109', 'timeInForce': 'GTC', 'triggerCondition': 'DEFAULT', 'triggerMode': 'TOP_OF_BOOK', 'price': '15140.9', 'reason': 'ON_FILL'}, {'id': '112', 'accountID': 'xxxxx', 'userID': xxxxx, 'batchID': '112', 'requestID': '24908231217089037', 'time': '2022-01-31T08:29:58.903631976Z', 'type': 'MARKET_ORDER', 'instrument': 'DE30_EUR', 'units': '-0.1', 'timeInForce': 'FOK', 'positionFill': 'DEFAULT', 'reason': 'CLIENT_ORDER'}, {'id': '113', 'accountID': 'xxxxx', 'userID': xxxxx, 'batchID': '112', 'requestID': '24908231217089037', 'time': '2022-01-31T08:29:58.903631976Z', 'type': 'ORDER_FILL', 'orderID': '112', 'instrument': 'DE30_EUR', 'units': '-0.1', 'requestedUnits': '-0.1', 'price': '15499.6', 'pl': '5.9200', 'quotePL': '5.92', 'financing': '0.0000', 'baseFinancing': '0.00000000000000', 'commission': '0.0000', 'accountBalance': '525.0693', 'gainQuoteHomeConversionFactor': '1', 'lossQuoteHomeConversionFactor': '1', 'guaranteedExecutionFee': '0.0000', 'quoteGuaranteedExecutionFee': '0', 'halfSpreadCost': '0.0850', 'fullVWAP': '15499.6', 'reason': 'MARKET_ORDER', 'tradesClosed': [{'tradeID': '109', 'units': '-0.1', 'realizedPL': '5.9200', 'financing': '0.0000', 'baseFinancing': '0.00000000000000', 'price': '15499.6', 'guaranteedExecutionFee': '0.0000', 'quoteGuaranteedExecutionFee': '0', 'halfSpreadCost': '0.0850', 'plHomeConversionCost': '0.00', 'baseFinancingHomeConversionCost': '0.00000000000000', 'guaranteedExecutionFeeHomeConversionCost': '0', 'homeConversionCost': '0.00000000000000'}], 'fullPrice': {'closeoutBid': '15496.4', 'closeoutAsk': '15504.5', 'timestamp': '2022-01-31T08:29:58.871175423Z', 'bids': [{'price': '15499.6', 'liquidity': '100'}, {'price': '15499.1', 'liquidity': '100'}, {'price': '15496.4', 'liquidity': '100'}], 'asks': [{'price': '15501.3', 'liquidity': '100'}, {'price': '15501.9', 'liquidity': '100'}, {'price': '15504.5', 'liquidity': '100'}]}, 'homeConversionFactors': {'gainQuoteHome': {'factor': '1'}, 'lossQuoteHome': {'factor': '1'}, 'gainBaseHome': {'factor': '15422.8980'}, 'lossBaseHome': {'factor': '15577.9020'}}, 'plHomeConversionCost': '0.00', 'baseFinancingHomeConversionCost': '0.00000000000000', 'guaranteedExecutionFeeHomeConversionCost': '0', 'homeConversionCost': '0.00000000000000'}, {'id': '114', 'accountID': 'xxxxx', 'userID': xxxxx, 'batchID': '112', 'requestID': '24908231217089037', 'time': '2022-01-31T08:29:58.903631976Z', 'type': 'ORDER_CANCEL', 'orderID': '110', 'reason': 'LINKED_TRADE_CLOSED', 'closedTradeID': '109', 'tradeCloseTransactionID': '113'}, {'id': '115', 'accountID': 'xxxxx', 'userID': xxxxx, 'batchID': '112', 'requestID': '24908231217089037', 'time': '2022-01-31T08:29:58.903631976Z', 'type': 'ORDER_CANCEL', 'orderID': '111', 'reason': 'LINKED_TRADE_CLOSED', 'closedTradeID': '109', 'tradeCloseTransactionID': '113'}], 'lastTransactionID': '115'}
        
input_dict = json_output
output_dict = [x for x in input_dict if x['type'] == 'ORDER_FILL'] # Filter if type is this
output_json = json.dumps(output_dict)
print(output_json)

Answer 1

我将详细谈谈RJ .阿德里亚森的评论。

您的变量json_output是一个字典。当迭代字典时，您将得到字典键(在本例中是transaction和lastTransactionID)。

您想要的是迭代根字典中transaction键中嵌套的列表。你可以这样做：

[x for x in json_output['transactions'] if x['type'] == 'ORDER_FILL']

Answer 2

您必须在事务列表中循环，而不是在dict中循环：

import json
...
input_dict = json_output
input_dict["transactions"] = [x for x in input_dict["transactions"] if x['type'] == 'ORDER_FILL'] # Filter if type is this
output_json = json.dumps(input_dict, indent=4)
print(output_json)