如何有效地更新两个结构的值

Golang常见问题解答介绍了有关地图和切片的指针：

映射和切片值的行为类似于指针：它们是包含指向基础映射或切片数据的指针的描述符。复制地图或切片值不会复制其指向的数据。复制接口值将复制存储在接口值中的事物。如果接口值包含一个结构，则复制接口值将复制该结构。如果接口值包含一个指针，则复制接口值将复制该指针，但不会复制它指向的数据。

在遍历内部模型切片时，

ConvertType

[]Models

for _, module := range int_cfg.models{}

上面的代码段正在创建的副本

int_cfg.models{}

索引切片模型以指向切片模型的确切基础数组，以将值更改为：

package mainimport (    "fmt"    "log"    "strings"    "gopkg.in/yaml.v2")//internal config model for parsingtype InternalModel struct {    Models []Model2 `yaml:"models"`}type Model2 struct {    Name   string `yaml:"name"`    Type   string `yaml:"type"`    Target string `yaml:"target"`}var internal_config = []byte(`  models:    - name: myapp      type: app1      target: ./    - name: myapp2      type: app2      target: ./`)type ExternalConfig struct {    Landscape []Zone `yaml:"Landscape"`}type Zone struct {    Zone   string  `yaml:"zone"`    Models []Model `yaml:"models"`}type Model struct {    AppType     string `yaml:"app-type"`    ServiceType string `yaml:"service-type"`}var external_config = []byte(`Landscape:  - zone: zone1    models:     - app-type: app1       service-type: GCP     - app-type: app2       service-type: AMAZON  - zone: zone2    models:     - app-type: app3       service-type: AZURE     - app-type: app4Í       service-type: HEROKU`)func main() {    //This is the internal config which needs to be update    internalConfiglYaml := InternalModel{}    err := yaml.Unmarshal(internal_config, &internalConfiglYaml)    if err != nil {        log.Fatalf("error in model internalConfiglYaml: %v", err)    }    fmt.Printf("%+vn", internalConfiglYaml)    //--------------------------Second config file-----------------------//    //This is the external config yaml    extConfigYaml := ExternalConfig{}    // var response interface{}    err = yaml.Unmarshal(external_config, &extConfigYaml)    if err != nil {        log.Fatalf("error in model extConfigYaml: %v", err)    }    fmt.Printf("%+vn", extConfigYaml)    landscape := "zone1"    modifiedConfig := ConvertTypes(&internalConfiglYaml, extConfigYaml, landscape)    fmt.Printf("%+vn", modifiedConfig)}// ConvertTypes for changing the intConfig struct typesfunc ConvertTypes(int_cfg *InternalModel, ext_config ExternalConfig, landscape string) (out_cfg *InternalModel) {    for _, module := range ext_config.Landscape {        if module.Zone == landscape { for i, value := range module.Models {     switch strings.Compare(value.AppType, int_cfg.Models[i].Type) {     case 0:         //here I hard-pred the value "GCP" but it should come from the yaml struct after parsing         int_cfg.Models[i].Type = value.ServiceType // should be something like ext_config.models.service-type when the key in the struct     default:     } }        }    }    return int_cfg}

如果检查以上代码片段，您还将认识到我已经更改了结构。

type InternalModel struct {    models []Model2 `yaml:"models"`}

首字母大写以使其可导出为：

type InternalModel struct {    Models []Model2 `yaml:"models"`}

由于struct

InternalModel

model

internal_config

我注意到的另一件事是您再次将字节转换为字节。没有必要。

err := yaml.Unmarshal([]byte(internal_config), &internalConfiglYaml)

所以我将其更改为：

err := yaml.Unmarshal(internal_config, &internalConfiglYaml)

因为

internal_config

[]byte