json-operations

在JSON中指定复杂条件操作。条件操作可以安全地对JSON值（Python字典）执行并返回布尔值。

from json_operations import execute
operations = [">", ["key", "items"], 30]
data1 = {
    "items": 31
}
data2 = {
    "items": 29
}

execute(operations, data1) # -> True
execute(operations, data2) # -> False

安全性

所有操作都是安全的（不使用eval）。如果是从不受信任的源获取输入，则强制执行长度限制是个好主意。

API

execute

对数据字典运行json操作。返回True/False。如果操作无效或键不存在，则可以引发JsonOperationError

from json_operations import execute

execute(<operations>, <data_dictionary>) -> bool

get_json_schema

返回json操作的JSON Schema。在运行操作之前验证操作很有用

from json_operations import get_json_schema

get_json_schema() -> Dict

get_keys

返回json操作内的键。这对于获取json操作所需的键列表以及验证所有键是否在数据字典内很有用

from json_operations import get_keys

get_keys(<operations>) -> List[Dict] 
# [{"name": "key1", "type": "number", "index": 0}, ...]

运算符

== (等于运算符)

检查一个值是否等于另一个值。

语法

["==", <operator_or_literal>, <operator_or_literal>]

示例

from json_operations import execute
operations = ["==", ["key", "items"], 30]
data1 = {
    "items": 30
}
data2 = {
    "items": 31
}

execute(operations, data1) # -> True
execute(operations, data2) # -> False

!= (不等于运算符)

检查一个值是否不等于另一个值。

语法

["!=", <operator_or_literal>, <operator_or_literal>]

示例

from json_operations import execute
operations = ["!=", ["key", "items"], 30]
data1 = {
    "items": 30
}
data2 = {
    "items": 31
}

execute(operations, data1) # -> False
execute(operations, data2) # -> True

> (大于运算符)

检查一个值是否大于另一个值。

语法

[">", <operator_or_literal>, <operator_or_literal>]

示例

from json_operations import execute
operations = [">", ["key", "items"], 30]
data1 = {
    "items": 31
}
data2 = {
    "items": 29
}

execute(operations, data1) # -> True
execute(operations, data2) # -> False

>= (大于等于运算符)

检查一个值是否大于或等于另一个值。

语法

[">=", <operator_or_literal>, <operator_or_literal>]

示例

from json_operations import execute
operations = [">=", ["key", "items"], 30]
data1 = {
    "items": 30
}
data2 = {
    "items": 29
}

execute(operations, data1) # -> True
execute(operations, data2) # -> False

< (小于运算符)

检查一个值是否小于另一个值。

语法

["<", <operator_or_literal>, <operator_or_literal>]

示例

from json_operations import execute
operations = ["<", ["key", "items"], 30]
data1 = {
    "items": 31
}
data2 = {
    "items": 29
}

execute(operations, data1) # -> False
execute(operations, data2) # -> True

<= (小于等于运算符)

检查一个值是否小于或等于另一个值。

语法

["<=", <operator_or_literal>, <operator_or_literal>]

示例

from json_operations import execute
operations = ["<=", ["key", "items"], 30]
data1 = {
    "items": 31
}
data2 = {
    "items": 30
}

execute(operations, data1) # -> False
execute(operations, data2) # -> True

in (在运算符)

检查一个值是否包含在另一个值中。

语法

["in", <operator_or_literal>, <operator_or_literal>]

示例

from json_operations import execute
operations = ["in", "my_type",  ["key", "types"]]
data1 = {
    "types": [
        "type1", "type2"
    ]
}
data2 = {
    "types": [
        "my_type", "type1"
    ]
}

execute(operations, data1) # -> False
execute(operations, data2) # -> True

!in (不在运算符)

检查一个值是否不包含在另一个值中。

语法

["!in", <operator_or_literal>, <operator_or_literal>]

示例

from json_operations import execute
operations = ["!in", "my_type",  ["key", "types"]]
data1 = {
    "types": [
        "type1", "type2"
    ]
}
data2 = {
    "types": [
        "my_type", "type1"
    ]
}

execute(operations, data1) # -> True
execute(operations, data2) # -> False

btw (介于运算符)

检查一个值是否介于两个值之间。等价于

low <= val <= high

低值和高值都包含。

语法

["btw", <value_operator_or_literal>, [<low_operator_or_literal>, <high_operator_or_literal>]]

示例

from json_operations import execute
operations = ["btw", ["key", "val"],  [1, 3]]
data1 = {
    "val": 2
}
data2 = {
    "val" : 4
}

execute(operations, data1) # -> True
execute(operations, data2) # -> False

& (交集运算符)

检查两个数组是否有任何共同成员

语法

["&", <value_operator_or_literal>, <value_operator_or_literal>]

示例

from json_operations import execute
operations = ["&", ["key", "val"],  [1, 2]]
data1 = {
    "val": [2,3]
}
data2 = {
    "val" : [3,4]
}

execute(operations, data1) # -> True
execute(operations, data2) # -> False

!& (非交集运算符)

检查两个数组是否有共同成员

语法

["!&", <value_operator_or_literal>, <value_operator_or_literal>]

示例

from json_operations import execute
operations = ["!&", ["key", "val"],  [1, 2]]
data1 = {
    "val": [2,3]
}
data2 = {
    "val" : [3,4]
}

execute(operations, data1) # -> False
execute(operations, data2) # -> True

并且（并且运算符）

检查所有值是否为真。 and 支持在其内部嵌套其他操作（参见复杂示例）。

语法

["and", ...<operators_or_literals>]

示例

from json_operations import execute
operations = ["and", ["key", "a"],  ["key", "b"]]
data1 = {
    "a": True,
    "b": False,
}
data2 = {
    "a": True,
    "b": True,
}

execute(operations, data1) # -> False
execute(operations, data2) # -> True

或（或运算符）

检查是否有任何值为真。 or 支持在其内部嵌套其他操作（参见复杂示例）。

语法

["or", ...<operators_or_literals>]

示例

from json_operations import execute
operations = ["or", ["key", "a"],  ["key", "b"]]
data1 = {
    "a": False,
    "b": False,
}
data2 = {
    "a": False,
    "b": True,
}

execute(operations, data1) # -> False
execute(operations, data2) # -> True

复杂运算符示例

from json_operations import execute

# (a > 1 or b < 5) and (c == 0 or d != 10) and (val in e or f >= 0)
operations = ["and", 
                ["or", [">", ["key", "a"], 1], ["<", ["key", "b"], 5]], 
                ["or", ["==", ["key", "c"], 0], ["!=", ["key", "d"], 10]],
                ["or", ["in", "val",  ["key", "e"]], [">=", ["key", "f"], 0]],
              ]
data1 = {
    "a": 0,
    "b": 5,
    "c": 0,
    "d": 9,
    "e": ["val", "another_val"],
    "f": 0,
}
data2 = {
    "a": 0,
    "b": 4,
    "c": 0,
    "d": 9,
    "e": ["val", "another_val"],
    "f": -1,
}
# (0 > 1 or 5 < 5) and (0 == 0 or 9 != 10) and (val in ["val", "another_val"] or 0 >= 0)
execute(operations, data1) # -> False

# (0 > 1 or 4 < 5) and (0 == 0 or 9 != 10) and (val in ["val", "another_val"] or -1 >= 0)
execute(operations, data2) # -> True

与 json-logic 的区别

https://jsonlogic.com/

• 操作始终类型安全（不能比较不同类型的值）。json-logic 会自动转换不同类型的值并进行比较，这可能导致难以发现的错误。
• 无效的操作会导致错误，而不是被忽略。json-logic 尝试避免所有错误，并继续处理意外的输入，这可能导致问题。
• 更紧凑且直观的语法

["or", ["key", "a"], ["key", "b"]]

与

{"or": [{"var": ["a"]}, {"var": ["b"]}]}

• 仅支持布尔逻辑。json-logic 支持所有类型的操作（加法、减法等），而不仅仅是布尔逻辑。