json - 如何从字符串表示形式的变量中获取嵌套结构？

Question

我有一个 JSON 文件看起来像下面这样

{
    "type": "Weekly",
    "clients": [
        "gozo",
        "dva"
    ],
    "sender": "no-reply@flowace.in",
    "recipients": {
        "gozo": [
            "a@gmail.com",
            "b@hotmail.com"
        ],
        "dva": [
            "c@gmail.com",
            "d@hotmail.com"
        ]
    },
    "features": [
        "Top5UsedApps",
        "TimeSpentOnEachL3",
        "NewlyAssignedL3",
        "HoursLogged"
    ],
    "dbCloning": [
        "dva"
    ] 
}

我已经映射了如下结构。

type receivers struct {
    Gozo []string `json:"gozo"`
    Dva  []string `json:"dva"`
    // Add more recievers
}

// Config -- The config object parsed from the JSON file
type Config struct {
    ReportType string    `json:"type"`
    Clients    []string  `json:"clients"`
    Sender     string    `json:"sender"`
    Recipients receivers `json:"recipients"`
    Cloning    []string  `json:"dbCloning"`
}

然后在另一个源文件的某处，我执行以下操作，

func main() {
    conf := LoadConfig(os.Args[1])
    for _, client := range conf.Clients {

        // Use the client variable of some other function calls

        fmt.Println(conf.Recipients[client]) // This will not work
}

现在我的问题是如何让它发挥作用。我无法直接遍历 conf.Recipients。

PS:考虑 LoadConfig 函数解码 JSON 并返回一个 conf 对象。

编辑 1: 看起来像是设计决策错误。现在使用 map[string][]string 的解决方案。但不将其标记为答案，因为需要知道在没有其他选择的所有情况下如何轻松完成。

Answer 1

问题是您的类型 receivers 不应该有命名字段。它应该是 map[string][]string。

这是一个工作示例:

package main

import (
    "encoding/json"
    "fmt"
)

type Config struct {
    ReportType string              `json:"type"`
    Clients    []string            `json:"clients"`
    Sender     string              `json:"sender"`
    Recipients map[string][]string `json:"recipients"`
    Cloning    []string            `json:"dbCloning"`
}

var data = []byte(`{
    "type": "Weekly",
    "clients": [
        "gozo",
        "dva"
    ],
    "sender": "no-reply@flowace.in",
    "recipients": {
        "gozo": [
            "a@gmail.com",
            "b@hotmail.com"
        ],
        "dva": [
            "c@gmail.com",
            "d@hotmail.com"
        ]
    },
    "features": [
        "Top5UsedApps",
        "TimeSpentOnEachL3",
        "NewlyAssignedL3",
        "HoursLogged"
    ],
    "dbCloning": [
        "dva"
    ] 
}`)

func main() {
    var conf Config
    json.Unmarshal(data, &conf)

    for _, client := range conf.Clients {
        fmt.Println(conf.Recipients[client])
    }
}

给出输出

[a@gmail.com b@hotmail.com]
[c@gmail.com d@hotmail.com]