JSONPath模板是由{}大括号括起来的JSONPath表达式组成。除了原始的JSONPath语法之外,我们还添加了三个函数:

    • 可选的$操作符,因为表达式总是默认从根对象开始。
    • 用""双引号来引用JSONPath表达式中的文本
    • 使用range操作符来迭代List。
      result对象被打印成String()函数。

    输出结果:

    1. {
    2. "kind": "List",
    3. "items":[
    4. {
    5. "kind":"None",
    6. "metadata":{"name":"127.0.0.1"},
    7. "status":{
    8. "capacity":{"cpu":"4"},
    9. "addresses":[{"type": "LegacyHostIP", "address":"127.0.0.1"}]
    10. }
    11. },
    12. {
    13. "kind":"None",
    14. "metadata":{"name":"127.0.0.2"},
    15. "status":{
    16. "capacity":{"cpu":"8"},
    17. "addresses":[
    18. {"type": "LegacyHostIP", "address":"127.0.0.2"},
    19. {"type": "another", "address":"127.0.0.3"}
    20. ]
    21. }
    22. }
    23. ],
    24. "users":[
    25. {
    26. "name": "myself",
    27. "user": {}
    28. },
    29. {
    30. "name": "e2e",
    31. "user": {"username": "admin", "password": "secret"}
    32. }
    33. ]
    34. }

    |Function|Description|Example|Result
    |text|the plain text|kind is {.kind}|kind is List
    |@|the current object|{@}|the same as input
    |. or []|child operator|{.kind} or {[‘kind’]}|List
    |..|recursive descent|{..name}|127.0.0.1 127.0.0.2 myself e2e
    ||wildcard. Get all objects|{.items[].metadata.name}|[127.0.0.1 127.0.0.2]
    |[start:end :step]|subscript operator|{.users[0].name}|myself
    |[,]|union operator|{.items[][‘metadata.name’, ‘status.capacity’]}|127.0.0.1 127.0.0.2 map[cpu:4] map[cpu:8]
    |?()|filter|{.users[?(@.name==”e2e”)].user.password}|secret
    |range, end|iterate list|{range .items[
    ]}[{.metadata.name}, {.status.capacity}] {end}|[127.0.0.1, map[cpu:4]] [127.0.0.2, map[cpu:8]]
    |””|quote interpreted string|{range .items[*]}{.metadata.name}{“\t”}{end}|127.0.0.1 127.0.0.2

    K8S中文社区微信公众号

    原文: http://docs.kubernetes.org.cn/67.html