json - 在嵌套的复杂 JSON 中搜索键

Question

我有一个带有树深度嵌套对象和对象列表的 JSON。我想在这样的 JSON 中搜索一个确切的键。

{
    "obj" : {
        "$ref" : "coll", 
        "$id" : ObjectId("5e37f7907303f206c87eb7d3"), 
        "$db": "db"
    }
    "objlist" : [
            {
                "$ref" : "coll", 
                "$id" : ObjectId("5ec57e3a72b4e11ac7239748"), 
                "$db": "db"
            }
            {
                "$ref" : "coll", 
                "$id" : ObjectId("5e26e09eb0d1301b1931e1aa"), 
                "$db": "db"
            }   ],
    "nestedobj" : {
            "created" : ISODate("2020-05-20T19:00:10.609Z"),
            "empty" : {

            },
            "obj" : {
                "$ref" : "coll", 
                "$id" : ObjectId("5ec57e3a72b4e11ac723974b"), 
                "$db": "db"
            }
            "obj" : {
                "$ref" : "coll", 
                "$id" : ObjectId("5f7206393c7b9885bc80607d"), 
                "$db": "db"
            }   },
    "obj" : {
            "x" : "xxx",
            "y" : "yyy",
            "z" : "zzz"
    },
    "nestedobjlist" : [
            {
                    "created" : ISODate("2020-05-14T12:35:14.340Z"),
                    "updated" : ISODate("2020-05-14T12:35:14.340Z"),
                    "obj" : {
                        "$ref" : "coll", 
                        "$id" : ObjectId("5e37f7907303f206c87eb7d3"), 
                        "$db": "db"
                    }
                    "x" : "xxx",
                    "obj" : {
                        "$ref" : "coll", 
                        "$id" : ObjectId("5ebd3ae7d5d9e5502a48cb23"), 
                        "$db": "db"
                    }           },
            {
                    "created" : ISODate("2020-05-14T12:35:14.340Z"),
                    "updated" : ISODate("2020-05-14T12:35:14.340Z"),
                    "obj" : {
                        "$ref" : "coll", 
                        "$id" : ObjectId("5e37f7907303f206c87eb7d3"), 
                        "$db": "db"
                    }
                    "x" : "xxx",
                    "obj" : {
                        "$ref" : "coll", 
                        "$id" : ObjectId("5f7206393c7b9885bc80607d"), 
                        "$db": "db"
                    }           }
    ],
    "empty" : {

    },
    "created" : ISODate("2020-01-21T10:33:50.378Z"),
    "x" : "xxx",
    "bool" : false,
    "int" : 0
    ...
}

我已经编写了这个有效的递归函数，但是对于大量条目来说复杂性不会变得太大吗？是否有更好的解决方案来遍历 JSON？

func recurs(doc bson.D, key string) {
    for _, k := range doc {
        switch e := k.Value.(type) {
        case primitive.D:
            if len(e) > 0 && e[0].Key == key {
                fmt.Println(e)
            } else {
                recurs(e)
            }
        case primitive.A:
            for _, r := range e {
                if len(r.(primitive.D)) > 0 && r.(primitive.D)[0].Key == key {
                    fmt.Println(r)
                } else {
                    recurs(r.(primitive.D))
                }
            }
        }
    }
}

我在 MongoDB 数据库中检索数据，然后在 BSON 中操作文档，其中：

type E struct {
    Key   string
    Value interface{}
}
type D []E
type A []D

标签： jsongorecursioncomplexity-theory

Answer 1

I'm not sure about BSON, but I've used tools like https://github.com/PaesslerAG/jsonpath to pull values out of big JSON docs where I didn't want to create a set of structures. jsonpath works like XPath, where you can parse the JSON into a generic interface{} and then give an expression to pull out the nodes you want.