访问值boto3 dictionary response

Question

我在尝试从boto3返回的数据中获取值时出错。我可以打印整个响应（见下文），但不知道需要做些什么才能使NetworkInterfaceId退出response。在

我在Python2.7.5中运行它，因为默认情况下，需要运行它的实例都是这样。我是python新手，希望能少一些简单的，谢谢你的帮助！在

错误

TypeError: list indices must be integers, not str

编码

^{pr2}$

回应

 {'ResponseMetadata': {'RetryAttempts': 0, 'HTTPStatusCode': 200, 'RequestId': 'a8e7ba60-7599-450a-a708-8d90e429d59e', 'HTTPHeaders': {'transfer-encoding': 'chunked', 'vary': 'Accept-Encoding', 'server': 'AmazonEC2', 'content-type': 'text/xml;charset=UTF-8', 'date': 'Wed, 08 Feb 2017 11:51:47 GMT'}}, u'RouteTables': [{u'Associations': [{u'SubnetId': 'subnet-d7040aaf', u'RouteTableAssociationId': 'rtbassoc-867a94ef', u'Main': False, u'RouteTableId': 'rtb-4a1efc23'}, {u'SubnetId': 'subnet-e0fcd3aa', u'RouteTableAssociationId': 'rtbassoc-9f7a94f6', u'Main': False, u'RouteTableId': 'rtb-4a1efc23'}], u'RouteTableId': 'rtb-4a1efc23', u'VpcId': 'vpc-0d00e264', u'PropagatingVgws': [{u'GatewayId': 'vgw-fcf479cc'}], u'Tags': [{u'Value': 'pub', u'Key': 'Name'}], u'Routes': [{u'GatewayId': 'local', u'DestinationCidrBlock': '172.28.0.0/16', u'State': 'active', u'Origin': 'CreateRouteTable'}, {u'Origin': 'CreateRoute', u'DestinationCidrBlock': '172.29.0.0/16', u'InstanceId': 'i-0b84e502d9dc49443', u'NetworkInterfaceId': 'eni-08f55373', u'State': 'active', u'InstanceOwnerId': '444456106883'}, {u'Origin': 'CreateRoute', u'DestinationCidrBlock': '172.31.0.0/16', u'InstanceId': 'i-0b84e502d9dc49443', u'NetworkInterfaceId': 'eni-08f55373', u'State': 'active', u'InstanceOwnerId': '444456106883'}, {u'GatewayId': 'igw-7b03e012', u'DestinationCidrBlock': '0.0.0.0/0', u'State': 'active', u'Origin': 'CreateRoute'}, {u'GatewayId': 'vgw-fcf479cc', u'DestinationCidrBlock': '10.114.112.192/27', u'State': 'active', u'Origin': 'EnableVgwRoutePropagation'}, {u'GatewayId': 'vgw-fcf479cc', u'DestinationCidrBlock': '10.114.210.160/27', u'State': 'active', u'Origin': 'EnableVgwRoutePropagation'}, {u'GatewayId': 'vgw-fcf479cc', u'DestinationCidrBlock': '10.138.172.32/27', u'State': 'active', u'Origin': 'EnableVgwRoutePropagation'}, {u'GatewayId': 'vgw-fcf479cc', u'DestinationCidrBlock': '10.138.172.96/27', u'State': 'active', u'Origin': 'EnableVgwRoutePropagation'}, {u'GatewayId': 'vgw-fcf479cc', u'DestinationCidrBlock': '10.114.105.128/26', u'State': 'active', u'Origin': 'EnableVgwRoutePropagation'}, {u'GatewayId': 'vgw-fcf479cc', u'DestinationCidrBlock': '10.115.80.0/26', u'State': 'active', u'Origin': 'EnableVgwRoutePropagation'}, {u'GatewayId': 'vgw-fcf479cc', u'DestinationCidrBlock': '10.115.131.0/26', u'State': 'active', u'Origin': 'EnableVgwRoutePropagation'}, {u'GatewayId': 'vgw-fcf479cc', u'DestinationCidrBlock': '10.138.17.128/26', u'State': 'active', u'Origin': 'EnableVgwRoutePropagation'}, {u'GatewayId': 'vgw-fcf479cc', u'DestinationCidrBlock': '10.138.83.64/26', u'State': 'active', u'Origin': 'EnableVgwRoutePropagation'}, {u'GatewayId': 'vgw-fcf479cc', u'DestinationCidrBlock': '10.138.180.128/26', u'State': 'active', u'Origin': 'EnableVgwRoutePropagation'}, {u'GatewayId': 'vgw-fcf479cc', u'DestinationCidrBlock': '10.192.0.0/16', u'State': 'active', u'Origin': 'EnableVgwRoutePropagation'}]}]} 

Answer 1

从documentation可以发现{}是一个列表。如果要获取NetworkInterfaceId，则应该遍历Routes。在

for route in response["RouteTables"][0]['Routes']:
    if 'NetworkInterfaceId' in route:
        print route['NetworkInterfaceId']

请注意，NetworkInterfaceId可能出现在响应中，也可能不存在。我从你贴在这里的回复中知道了。在