json資料檢索與定位之jsonPath類庫
by:授客 QQ：1033553122
實踐環境
win7 64
Python 3.4.0
jsonpath_ng-1.4.3-py2.py3-none-any.whl
下載地址：
https://pypi.org/project/jsonpath-ng/#files
https://pan.baidu.com/s/1AdbGqz1brNYBOqmIbWaAYg
使用詳解
官方例項
>>> from jsonpath_ng import jsonpath, parse
>>> jsonpath_expr = parse(`foo[*].baz`)
# 提取值
>>> [match.value for match in jsonpath_expr.find({`foo`:[{`baz`:1}, {`baz`:2}]})]
[1, 2]
# 獲取匹配值對應的路徑
>>> [str(match.full_path) for match in jsonpath_expr.find({`foo`: [{`baz`: 1}, {`baz`: 2}]})]
[`foo.[0].baz`, `foo.[1].baz`]
# 自動提供id
>>> [match.value for match in parse(`foo[*].id`).find({`foo`: [{`id`: `bizzle`}, {`baz`: 3}]})]
[`bizzle`]
>>> jsonpath.auto_id_field = `id`
>>> [match.value for match in parse(`foo[*].id`).find({`foo`: [{`id`: `bizzle`}, {`baz`: 3}]})]
[`foo.bizzle`, `foo.[1]`]
# 擴充套件功能之一 命名操作符 `parent`
>>> [match.value for match in parse(`a.*.b.`parent`.c`).find({`a`: {`x`: {`b`: 1, `c`: `number one`}, `y`: {`b`: 2, `c`: `number two`}}})]
[`number one`, `number two`]
>>> [`number two`, `number one`]
使用擴充套件的解析器
好處是有更強大的擴充套件功能
>>> from jsonpath_ng.ext import parse
>>> jsonpath_expr = parse(`foo[*].baz`)
jsonpath 語法
基礎語法(Atomic expressions)
$ 根物件
`this` 當前物件
`foo` More generally, this syntax allows “named operators” to extend JSONPath is arbitrary ways
field 指定具體的欄位
[ field ] 同field
[ idx ] 陣列訪問 Array access, described below (this is always unambiguous with field access)
例子
獲取根物件
>>> parse(`$`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}]})
[DatumInContext(value={`key2`: {`id`: 2}, `key3`: [{`id`: 3}, {`name`: `shouke`}], `key1`: {`id`: 1}}, path=Root(), context=None)]
>>> [match.value for match in parse(`$`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}]})]
[{`key2`: {`id`: 2}, `key3`: [{`id`: 3}, {`name`: `shouke`}], `key1`: {`id`: 1}}]
獲取一級鍵對應的值
>>> [match.value for match in parse(`key1`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}]})]
[{`id`: 1}]
>>> [match.value for match in parse(`[key1]`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}]})]
[{`id`: 1}]
# 注意：單獨使用 filed、 [filed] 語法，field僅支援字典的一級鍵
[{`key2`: {`id`: 2}, `key3`: [{`id`: 3}, {`name`: `shouke`}], `key1`: {`id`: 1}}]
>>> [match.value for match in parse(`id`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}]})]
[]
# 注意：單獨使用 filed、 [filed] 語法，根物件必須是字典，不能是陣列
>>> [match.value for match in parse(`[key1]`).find([{`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}]}])]
[]
陣列訪問
>>> [match.value for match in parse(`[0]`).find([{`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}]}])]
[{`key2`: {`id`: 2}, `key3`: [{`id`: 3}, {`name`: `shouke`}], `key1`: {`id`: 1}}]
jsonpath操作符
jsonpath1 . jsonpath2 匹配jsonpath2，並且父節點匹配jsonpath1的所有節點(All nodes matched by jsonpath2 starting at any node matching jsonpath1) 注意：僅針對字典可用
注：有無空格不影響，比如jsonpath1.jsonpath2 下同
jsonpath [ whatever ] 如果是字典，同jsonpath.whatever，如果是陣列，則表示按索引訪問陣列
jsonpath1 .. jsonpath2 匹配jsonpath2，並且由匹配jsonpath1的父節點派生的所有節點
jsonpath1 where jsonpath2 匹配jsonpath1並且攜帶一個匹配jsonpath2直接子節點(非派生子節點)的所有節點（Any nodes matching jsonpath1 with a child matching jsonpath2）
jsonpath1 | jsonpath2 匹配jsonpath1，或者jsonpath2的所有節點的集合（注：有時候結果似乎和描述不符，具體見例子
例子
jsonpath1 . jsonpath2
>>> [match.value for match in parse(`key1.id`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}]})]
[1]
jsonpath [ whatever ]
>>> [match.value for match in parse(`key1[id]`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}]})]
[1]
>>> [match.value for match in parse(`key3[0]`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}]})]
[{`id`: 3}]
jsonpath1 .. jsonpath2
>>> [match.value for match in parse(`key3..id`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:{`key4`:{`key5`:{`id`:3, `name`:`shouke`}}}})]
[3]
>>> [match.value for match in parse(`key3..id`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}, {`id`:4, `name`:`keshou`}]})]
[3, 4]
jsonpath1 where jsonpath2
>>> [match.value for match in parse(`key2 where id`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}, {`id`:4, `name`:`keshou`
[{`id`: 2}]
注意：匹配jsonpath2的必須是直接子節點
>>> [match.value for match in parse(`key3 where id`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}, {`id`:4, `name`:`keshou`
[]
>>> [match.value for match in parse(`key3 where id`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:{`key4`:{`key5`:{`id`:3, `name`:`shouke`}}}})]
[]
jsonpath1 | jsonpath2
>>> [match.value for match in parse(`key1 | key3 `).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:{`key4`:{`key5`:{`id`:3, `name`:`shouke`}}}})]
[{`id`: 1}, {`key4`: {`key5`: {`name`: `shouke`, `id`: 3}}}]
>>> [match.value for match in parse(`key1 | key3.key4 `).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:{`key4`:{`key5`:{`id`:3, `name`:`shouke`}}}})]
[{`key5`: {`name`: `shouke`, `id`: 3}}]
欄位說明(field)
fieldname 來自當前物件的欄位名稱
“fieldname” 同上，允許fieldname中包含指定字元
`fieldname` 同上
* 任意欄位名稱
field , field 指定多個欄位
例子
*
>>> [match.value for match in parse(`key1.*`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:{`key4`:{`key5`:{`id`:3, `name`:`shouke`}}}})]
[1]
注意：如果是jsonpath1.* 返回的是最後層級的值
>>> [match.value for match in parse(`key3.*`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:{`key4`:{`key5`:{`id`:3, `name`:`shouke`}}}})]
[{`key5`: {`name`: `shouke`, `id`: 3}}]
>>> [match.value for match in parse(`key3.*`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}, {`id`:4, `name`:`keshou`}]})]
[]
>>> [match.value for match in parse(`key1, key2, key3`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}, {`id`:4, `name`:`kesh
[{`id`: 1}, {`id`: 2}, [{`id`: 3}, {`name`: `shouke`}, {`name`: `keshou`, `id`: 4}]]
>>> [match.value for match in parse(`*.*[*]`).find({`root`:{`key`:[{`id`:`tizza`}, {`name`:`hizza`}]}})]
[{`id`: `tizza`}, {`name`: `hizza`}]
field , field 指定多個欄位
>>> [match.value for match in parse(`key1, key2, key3`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}, {`id`:4, `name`:`keshou`}]
[{`id`: 1}, {`id`: 2}, [{`id`: 3}, {`name`: `shouke`}, {`name`: `keshou`, `id`: 4}]]
陣列索引說明（idx）
[n] 陣列索引
[start?:end?] 含義同python的陣列切片，注意：陣列索引不包含end,可以不指定start, end，或者兩者之一
[*] 任意索引，表示返回整個陣列元素，等同於[:]
例子
[*]
[match.value for match in parse(`key3[*]`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}, {`id`:4, `name`:`keshou`}]})]
[{`id`: 3}, {`name`: `shouke`}, {`name`: `keshou`, `id`: 4}]
[start?:end?]
>>> [match.value for match in parse(`key3[0:1]`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}, {`id`:4, `name`:`keshou`}]})]
[{`id`: 3}]
>>> [match.value for match in parse(`key3[0:]`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}, {`id`:4, `name`:`keshou`}]})]
[{`id`: 3}, {`name`: `shouke`}, {`name`: `keshou`, `id`: 4}]
>>> [match.value for match in parse(`key3[:1]`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}, {`id`:4, `name`:`keshou`}]})]
[{`id`: 3}]
>>> [match.value for match in parse(`key3[:]`).find({`key1`:{`id`: 1}, `key2`:{`id`: 2}, `key3`:[{`id`:3}, {`name`:`shouke`}, {`id`:4, `name`:`keshou`}]})]
[{`id`: 3}, {`name`: `shouke`}, {`name`: `keshou`, `id`: 4}]
>>>
更多功能參考官方文件
參考連結
https://pypi.org/project/jsonpath-ng/#files