Question

我正在尝试创建一个端点Go API，供前端JavaScript图形库使用。

应该发生什么：

/数据端点以获取JSON数据数组。
数据只是go结构的一部分，在此示例中仅为两个，但将超过10000。
图形库需要其他元数据。将其保存为名为AdditionalInfo的变量。
问题是，当我想对AdditionalInfo + AllAgents进行编码时，它不允许我将带有一部分结构的字符串连接起来。
在结构片的末尾还需要有]`以使其有效为JSON

问题：

如何在结构的前面和后面添加其他数据？
将结构附加到结构的切片上是否有效？

最好创建一个已知长度的切片，然后使用range附加到它上面？

package main

import (
    "encoding/json"
    "fmt"
    "log"
    "net/http"
    "os"
)

func main() {
    port := os.Getenv("PORT")
    if port == "" {
        port = "443"
        log.Printf("Defaulting to port %s", port)
    }

    http.HandleFunc("/data", TrySnipped)
    log.Fatal(http.ListenAndServe(fmt.Sprintf(":%s", port), nil))

}

func TrySnipped(w http.ResponseWriter, r *http.Request) {
    w.Header().Add("Content-Type", "application/json")
    var AllAgents []SingleAgent
    AllAgents = append(AllAgents, FirstAgent)
    AllAgents = append(AllAgents, SecondAgent)

    json.NewEncoder(w).Encode(AllAgents)

}

var AdditionalInfo = `"meta": {
            "page": 1,
            "pages": 1,
            "perpage": -1,
            "total": 350,
            "sort": "asc",
            "field": "RecordID"
        },
        "data": [`

type SingleAgent struct {
    RecordID             string `json:"RecordID"`
    OldEmployeeID        string `json:"OldEmployeeID"`
    NewEmployeeID        string `json:"NewEmployeeID"`
    AgentRank            int    `json:"AgentRank"`
    AgentName            string `json:"AgentName"`
    AgentEmail           string `json:"AgentEmail"`
    TeamManager          string `json:"TeamManager"`
    LineOfBusiness       string `json:"LineOfBusiness"`
    FitnessCampStartDate string `json:"FitnessCampStartDate"`
    FitnessCampEndDate   string `json:"FitnessCampEndDate"`
    FitnessCampStatus    int    `json:"FitnessCampStatus"`
    AgentFitnessRank     int    `json:"AgentFitnessRank"`
    LatestMetricA        int    `json:"MetricA"`
    LatestMetricB        int    `json:"MetricB"`
    LatestMetricC        int    `json:"MetricC"`
    LatestMetricD        int    `json:"MetricD"`
    LatestMetricE        int    `json:"MetricD"`
    SiteName             string `json:"SiteName"`
    SiteID               string `json:"SiteID"`
    PostCampWeek1        string `json:"PostCampWeek1"`
    PostCampWeek2        string `json:"PostCampWeek2"`
    PostCampWeek3        string `json:"PostCampWeek3"`
}

var FirstAgent = SingleAgent{
    RecordID:             "30",
    OldEmployeeID:        "785114544",
    NewEmployeeID:        "10785114544",
    AgentRank:            3,
    AgentName:            "Shandeigh Rawsen",
    AgentEmail:           "shandeigh.rawsen@gmail.com",
    TeamManager:          "Oliver Lamplugh",
    LineOfBusiness:       "BMS",
    FitnessCampStartDate: "8/13/2018",
    FitnessCampEndDate:   "10/7/2018",
    FitnessCampStatus:    1,
    AgentFitnessRank:     1,
    LatestMetricA:        77,
    LatestMetricB:        167,
    LatestMetricC:        496,
    LatestMetricD:        72,
    LatestMetricE:        80,
    SiteName:             "Montreal",
    SiteID:               "4",
    PostCampWeek1:        "10/2/2018",
    PostCampWeek2:        "10/9/2018",
    PostCampWeek3:        "10/19/2018",
}
var SecondAgent = SingleAgent{
    RecordID:             "29",
    OldEmployeeID:        "980433290",
    NewEmployeeID:        "10980433290",
    AgentRank:            4,
    AgentName:            "Terrijo Dewberry",
    AgentEmail:           "terrijo.deberry@gmail.com",
    TeamManager:          "Oliver Lamplugh",
    LineOfBusiness:       "BTSW",
    FitnessCampStartDate: "7/28/2018",
    FitnessCampEndDate:   "9/23/2018",
    FitnessCampStatus:    2,
    AgentFitnessRank:     2,
    LatestMetricA:        88,
    LatestMetricB:        92,
    LatestMetricC:        716,
    LatestMetricD:        78,
    LatestMetricE:        66,
    SiteName:             "Montreal",
    SiteID:               "2",
    PostCampWeek1:        "10/2/2018",
    PostCampWeek2:        "10/9/2018",
    PostCampWeek3:        "10/15/2018",
}

Answer 1

将其他信息，座席和结束括号写到响应中：

 io.WriteString(w, "{")
 io.WriteString(w, AdditionalInfo)
 json.NewEncoder(w).Encode(AllAgents)
 io.WriteString(w, "]}")  // closing ] for data and closing } for root

请注意，这在代理周围编码了[ ]的两个级别。尚不清楚这是否是您想要的。

另一种方法是创建一个匹配输出结构的Go值并将其编码：

v := map[string]interface{}{
    "meta": map[string]interface{}{
        "page":    1,
        "pages":   1,
        "perpage": -1,
        "total":   350,
        "sort":    "asc",
        "field":   "RecordID",
    },
    "data": AllAgents,
 }
 if err := json.NewEncoder(w).Encode(v); err != nil {
    // handle error
 }

同样，目前尚不清楚您希望在代理周围进行多少嵌套。您可能需要以下变体：

v := map[string]interface{}{
    "meta": map[string]interface{}{
        "page":    1,
        "pages":   1,
        "perpage": -1,
        "total":   350,
        "sort":    "asc",
        "field":   "RecordID",
    },
    "data": []interface{}{AllAgents},
 }
 if err := json.NewEncoder(w).Encode(v); err != nil {
    // handle error
 }

re：效率创建最终尺寸的切片通常比使用append逐渐增加切片的效率更高。通过使用切片指针[]*SingleAgent代替切片结构值[]SingleAgent可能会获得一些效果。

将字符串连接到结构片段

1 个答案: