python - 用python从嵌套的json中提取
问题描述
我正在尝试从下面的 json 输出中提取值，我正在使用 python 提取键和值，为了实现我尝试使用下面的代码并且我能够获取该值，但它也显示了以下错误。
“KeyError：'集群成员名称'”
有没有更好的方法来实现这一点是python？
resp_dict2 = json.loads(r23con)
for each in resp_dict2['objects']:
print each['cluster-member-names']
================================
{
"objects" : [ {
"uid" : "b369119d-e3e5-4d12-9bb5-11d37524cf59",
"name" : "clus-cn-1",
"type" : "CpmiGatewayCluster",
"domain" : {
"uid" : "c3ca57db-f2cb-4ec0-bea7-2dca87d30d77",
"name" : "dom-cn-1",
"domain-type" : "domain"
},
"policy" : {
"access-policy-installed" : true,
"access-policy-name" : "Standard",
"access-policy-installation-date" : {
"posix" : 1531837503075,
"iso-8601" : "2018-07-17T19:55+0530"
},
"threat-policy-installed" : false
},
"operating-system" : "Gaia",
"hardware" : "Open server",
"version" : "R80.10",
"ipv4-address" : "53.126.102.12",
"network-security-blades" : {
"firewall" : true
},
"management-blades" : { },
"cluster-member-names" : [ "dev-cn-c1", "dev-cn-c2" ],
"vpn-encryption-domain" : "addresses_behind_gw",
"sic-status" : "uninitialized",
"tags" : [ ],
"icon" : "NetworkObjects/cluster",
"groups" : [ ],
"comments" : "",
"color" : "black",
"meta-info" : {
"lock" : "unlocked",
"validation-state" : "ok",
"last-modify-time" : {
"posix" : 1531837459783,
"iso-8601" : "2018-07-17T19:54+0530"
},
"last-modifier" : "System",
"creation-time" : {
"posix" : 1531824670186,
"iso-8601" : "2018-07-17T16:21+0530"
},
"creator" : "System"
},
"read-only" : true
}, {
"uid" : "e24905b9-1cc7-4e8b-af2f-60553bfc2071",
"name" : "clus-cn-2",
"type" : "CpmiGatewayCluster",
"domain" : {
"uid" : "45d0fa6f-d218-455b-8fd9-c0c563e0e942",
"name" : "dom-cn-2",
"domain-type" : "domain"
},
"policy" : {
"access-policy-installed" : true,
"access-policy-name" : "Standard",
"access-policy-installation-date" : {
"posix" : 1531837708659,
"iso-8601" : "2018-07-17T19:58+0530"
},
"threat-policy-installed" : false
},
"operating-system" : "Gaia",
"hardware" : "Open server",
"version" : "R80.10",
"ipv4-address" : "53.126.102.16",
"network-security-blades" : {
"firewall" : true
},
"management-blades" : { },
"cluster-member-names" : [ "dev-cn-c3", "dev-cn-c4" ],
"vpn-encryption-domain" : "addresses_behind_gw",
"sic-status" : "uninitialized",
"tags" : [ ],
"icon" : "NetworkObjects/cluster",
"groups" : [ ],
"comments" : "",
"color" : "black",
"meta-info" : {
"lock" : "unlocked",
"validation-state" : "ok",
"last-modify-time" : {
"posix" : 1531837666757,
"iso-8601" : "2018-07-17T19:57+0530"
},
"last-modifier" : "System",
"creation-time" : {
"posix" : 1531833469334,
"iso-8601" : "2018-07-17T18:47+0530"
},
"creator" : "System"
},
"read-only" : true
}, {
"uid" : "cf129905-3382-43df-bd4f-e0420a2ae425",
"name" : "dev-cn-c1",
"type" : "CpmiClusterMember",
"domain" : {
"uid" : "c3ca57db-f2cb-4ec0-bea7-2dca87d30d77",
"name" : "dom-cn-1",
"domain-type" : "domain"
},
"policy" : { },
"ipv4-address" : "53.126.102.9",
"interfaces" : [ {
"interface-name" : "eth0",
"ipv4-address" : "53.126.102.9",
"ipv4-network-mask" : "255.255.255.192",
"ipv4-mask-length" : 26,
"dynamic-ip" : false,
"topology" : {
"leads-to-internet" : true
}
}, {
"interface-name" : "eth1",
"ipv4-address" : "10.10.10.1",
"ipv4-network-mask" : "255.255.255.240",
"ipv4-mask-length" : 28,
"dynamic-ip" : false,
"topology" : {
"leads-to-internet" : false,
"ip-address-behind-this-interface" : "network defined by the interface ip and net mask",
"leads-to-dmz" : false
}
} ],
"sic-status" : "communicating",
"tags" : [ ],
"icon" : "NetworkObjects/Cluster_member",
"groups" : [ ],
"comments" : "",
"color" : "black",
"meta-info" : {
"lock" : "unlocked",
"validation-state" : "ok",
"last-modify-time" : {
"posix" : 1531837458178,
"iso-8601" : "2018-07-17T19:54+0530"
},
"last-modifier" : "System",
"creation-time" : {
"posix" : 1531824670721,
"iso-8601" : "2018-07-17T16:21+0530"
},
"creator" : "System"
},
"read-only" : true
}, {
"uid" : "d35c980f-ba0f-40af-8593-466ef4caf90c",
"name" : "dev-cn-c2",
"type" : "CpmiClusterMember",
"domain" : {
"uid" : "c3ca57db-f2cb-4ec0-bea7-2dca87d30d77",
"name" : "dom-cn-1",
"domain-type" : "domain"
},
"policy" : { },
"ipv4-address" : "53.126.102.10",
"interfaces" : [ {
"interface-name" : "eth1",
"ipv4-address" : "10.10.10.2",
"ipv4-network-mask" : "255.255.255.240",
"ipv4-mask-length" : 28,
"dynamic-ip" : false,
"topology" : {
"leads-to-internet" : false,
"ip-address-behind-this-interface" : "network defined by the interface ip and net mask",
"leads-to-dmz" : false
}
}, {
"interface-name" : "eth0",
"ipv4-address" : "53.126.102.10",
"ipv4-network-mask" : "255.255.255.192",
"ipv4-mask-length" : 26,
"dynamic-ip" : false,
"topology" : {
"leads-to-internet" : true
}
} ],
"sic-status" : "communicating",
"tags" : [ ],
"icon" : "NetworkObjects/Cluster_member",
"groups" : [ ],
"comments" : "",
"color" : "black",
"meta-info" : {
"lock" : "unlocked",
"validation-state" : "ok",
"last-modify-time" : {
"posix" : 1531837458844,
"iso-8601" : "2018-07-17T19:54+0530"
},
"last-modifier" : "System",
"creation-time" : {
"posix" : 1531824673679,
"iso-8601" : "2018-07-17T16:21+0530"
},
"creator" : "System"
},
"read-only" : true
}, {
"uid" : "2a35580d-865b-491f-b5ac-6bff38bedc03",
"name" : "dev-cn-c3",
"type" : "CpmiClusterMember",
"domain" : {
"uid" : "45d0fa6f-d218-455b-8fd9-c0c563e0e942",
"name" : "dom-cn-2",
"domain-type" : "domain"
},
"policy" : { },
"ipv4-address" : "53.126.102.13",
"interfaces" : [ {
"interface-name" : "eth1",
"ipv4-address" : "10.10.10.21",
"ipv4-network-mask" : "255.255.255.240",
"ipv4-mask-length" : 28,
"dynamic-ip" : false,
"topology" : {
"leads-to-internet" : false,
"ip-address-behind-this-interface" : "network defined by the interface ip and net mask",
"leads-to-dmz" : false
}
}, {
"interface-name" : "eth0",
"ipv4-address" : "53.126.102.13",
"ipv4-network-mask" : "255.255.255.192",
"ipv4-mask-length" : 26,
"dynamic-ip" : false,
"topology" : {
"leads-to-internet" : true
}
} ],
"sic-status" : "communicating",
"tags" : [ ],
"icon" : "NetworkObjects/Cluster_member",
"groups" : [ ],
"comments" : "",
"color" : "black",
"meta-info" : {
"lock" : "unlocked",
"validation-state" : "ok",
"last-modify-time" : {
"posix" : 1531837665452,
"iso-8601" : "2018-07-17T19:57+0530"
},
"last-modifier" : "System",
"creation-time" : {
"posix" : 1531833469733,
"iso-8601" : "2018-07-17T18:47+0530"
},
"creator" : "System"
},
"read-only" : true
}, {
"uid" : "97b381c4-1b7c-4cd8-958c-f7a062bb731f",
"name" : "dev-cn-c4",
"type" : "CpmiClusterMember",
"domain" : {
"uid" : "45d0fa6f-d218-455b-8fd9-c0c563e0e942",
"name" : "dom-cn-2",
"domain-type" : "domain"
},
"policy" : { },
"ipv4-address" : "53.126.102.14",
"interfaces" : [ {
"interface-name" : "eth1",
"ipv4-address" : "10.10.10.20",
"ipv4-network-mask" : "255.255.255.240",
"ipv4-mask-length" : 28,
"dynamic-ip" : false,
"topology" : {
"leads-to-internet" : false,
"ip-address-behind-this-interface" : "network defined by the interface ip and net mask",
"leads-to-dmz" : false
}
}, {
"interface-name" : "eth0",
"ipv4-address" : "53.126.102.14",
"ipv4-network-mask" : "255.255.255.192",
"ipv4-mask-length" : 26,
"dynamic-ip" : false,
"topology" : {
"leads-to-internet" : true
}
} ],
"sic-status" : "communicating",
"tags" : [ ],
"icon" : "NetworkObjects/Cluster_member",
"groups" : [ ],
"comments" : "",
"color" : "black",
"meta-info" : {
"lock" : "unlocked",
"validation-state" : "ok",
"last-modify-time" : {
"posix" : 1531837666008,
"iso-8601" : "2018-07-17T19:57+0530"
},
"last-modifier" : "System",
"creation-time" : {
"posix" : 1531833470854,
"iso-8601" : "2018-07-17T18:47+0530"
},
"creator" : "System"
},
"read-only" : true
}, {
"uid" : "ee6bad53-697a-4250-bd31-8c86886b3a45",
"name" : "dom_cn_1_Server",
"type" : "CpmiHostCkp",
"domain" : {
"uid" : "c3ca57db-f2cb-4ec0-bea7-2dca87d30d77",
"name" : "dom-cn-1",
"domain-type" : "domain"
},
"policy" : { },
"operating-system" : "Unknown OS",
"hardware" : "Open server",
"version" : "R80.10",
"ipv4-address" : "53.126.102.11",
"network-security-blades" : { },
"management-blades" : {
"network-policy-management" : true,
"logging-and-status" : true
},
"sic-status" : "uninitialized",
"tags" : [ ],
"icon" : "NetworkObjects/CheckPoint/Hosts/xHost_CP",
"groups" : [ ],
"comments" : "Domain Management Server",
"color" : "black",
"meta-info" : {
"lock" : "unlocked",
"validation-state" : "ok",
"last-modify-time" : {
"posix" : 1531803602643,
"iso-8601" : "2018-07-17T10:30+0530"
},
"last-modifier" : "System",
"creation-time" : {
"posix" : 1531803574293,
"iso-8601" : "2018-07-17T10:29+0530"
},
"creator" : "System"
},
"read-only" : true
}, {
"uid" : "d9539c38-8a7d-4c65-8c8e-a11e855409e0",
"name" : "dom_cn_2",
"type" : "CpmiHostCkp",
"domain" : {
"uid" : "45d0fa6f-d218-455b-8fd9-c0c563e0e942",
"name" : "dom-cn-2",
"domain-type" : "domain"
},
"policy" : { },
"operating-system" : "Unknown OS",
"hardware" : "Open server",
"version" : "R80.10",
"ipv4-address" : "53.126.102.15",
"network-security-blades" : { },
"management-blades" : {
"network-policy-management" : true,
"logging-and-status" : true
},
"sic-status" : "uninitialized",
"tags" : [ ],
"icon" : "NetworkObjects/CheckPoint/Hosts/xHost_CP",
"groups" : [ ],
"comments" : "Domain Management Server",
"color" : "black",
"meta-info" : {
"lock" : "unlocked",
"validation-state" : "ok",
"last-modify-time" : {
"posix" : 1531803969445,
"iso-8601" : "2018-07-17T10:36+0530"
},
"last-modifier" : "System",
"creation-time" : {
"posix" : 1531803941175,
"iso-8601" : "2018-07-17T10:35+0530"
},
"creator" : "System"
},
"read-only" : true
} ],
"from" : 1,
"to" : 8,
"total" : 8
}
解决方案
问题是并非每个 Json 对象objects都有一个cluster-member-names字段。因此，当遍历所有对象并尝试访问该字段时（当它不存在时），它会抛出该 KeyError。
要解决此问题，您可以使用该dict.get('field_name', default_value)功能，如果该字段不存在，该功能将允许您指定默认值。默认情况下，这通常是None.
使用示例dict.get：
resp_dict2 = json.loads(r23con)
for each in resp_dict2['objects']:
val = each.get('cluster-member-names')
if val is not None:
print(val)
推荐阅读
- javascript - 自定义搜索 - 如何根据数组中的值重新排序数组
- reactjs - 如何读取 React 应用程序中的 props 表达式
- excel - 在工作簿中传输数据
- python - 元组索引超出范围：音频到频谱图
- angular - Angular6 在指令本身中获取所有具有相同指令名称的元素
- c# - 任务
- microsoft-graph-api - 使用 Graph API 从文档 URL 获取 ItemId
- video-streaming - 播放 HLS 流时三星 Tizen AVPlayer 错误
- php - 无法通过 AJAX 将数据传递给 Laravel
- python - 为什么此 Python 语句中的“和/或”操作出现意外行为？