Go语言之读取yaml配置文件，转换成struct结构，json形式输出
1、例子1
1.1、yaml文件内容如下:
host: localhost:3306
user: root
pwd: 123456
dbname: test 1.2、代码如下：
//将yaml文件，转换成对象，再转换成json格式输出
package main
import (
"encoding/json"
"fmt"
"gopkg.in/yaml.v2"
"io/ioutil"
)
//定义conf类型
//类型里的属性，全是配置文件里的属性
type conf struct {
Host string `yaml: "host"`
User string `yaml:"user"`
Pwd string `yaml:"pwd"`
Dbname string `yaml:"dbname"`
}
func main() {
var c conf
//读取yaml配置文件
conf := c.getConf()
fmt.Println(conf)
//将对象，转换成json格式
data, err := json.Marshal(conf)
if err != nil {
fmt.Println("err:\t", err.Error())
return
}
//最终以json格式，输出
fmt.Println("data:\t", string(data))
}
//读取Yaml配置文件,
//并转换成conf对象
func (c *conf) getConf() *conf {
//应该是 绝对地址
yamlFile, err := ioutil.ReadFile("E:\\Program\\go2\\goPath\\src\\xingej-go\\xingej-go\\xingej-go666\\lib\\yaml\\conf.yaml")
if err != nil {
fmt.Println(err.Error())
}
err = yaml.Unmarshal(yamlFile, c)
if err != nil {
fmt.Println(err.Error())
}
return c
}
如果某一个包，本地没有的话，可以在cmd中使用下面的命令，进行下载，如:
go get gopkg.in/yaml.v2
==基本格式:== go get 包的路径
2、例子2，该配置文件中，存在map,slice类型，稍微复杂些
2.1、 配置文件内容：
apiVersion: v1
kind: KafkaCluster2
metadata:
name: kafka-operator
labels:
config1:
address: kafka-operator-labels-01
id: kafka-operator-labels-02
name: mysql-example-cluster-master
nodeName: 172.16.91.21
role: master
config2:
address: kafka-operator-labels-01
id: kafka-operator-labels-02
name: mysql-example-cluster-slave
nodeName: 172.16.91.110
role: slave
spec:
replicas: 1
name: kafka-controller
image: 172.16.26.4:5000/nginx
ports: 8088
conditions:
- containerPort: 8080
requests:
cpu: "0.25"
memory: "512Mi"
limits:
cpu: "0.25"
memory: "1Gi"
- containerPort: 9090
requests:
cpu: "0.33"
memory: "333Mi"
limits:
cpu: "0.55"
memory: "5Gi"2.2、 代码如下：
package main
import (
"encoding/json"
"fmt"
"gopkg.in/yaml.v2"
"io/ioutil"
)
type KafkaCluster struct {
ApiVersion string `yaml:"apiVersion"`
Kind string `yaml: "kind"`
Metadata Metadata `yaml: "metadata"`
Spec Spec `yaml: "spec"`
}
type Metadata struct {
Name string `yaml:"name"`
//map类型
Labels map[string]*NodeServer `yaml:"labels"`
}
type NodeServer struct {
Address string `yaml: "address"`
Id string `yaml: "id"`
Name string `yaml: "name"`
//注意，属性里，如果有大写的话，tag里不能存在空格
//如yaml: "nodeName" 格式是错误的，中间多了一个空格，不能识别的
NodeName string `yaml:"nodeName"`
Role string `yaml: "role"`
}
type Spec struct {
Replicas int `yaml: "replicas"`
Name string `yaml: "name"`
Image string `yaml: "iamge"`
Ports int `yaml: "ports"`
//slice类型
Conditions []Conditions `yaml: "conditions"`
}
type Conditions struct {
ContainerPort string `yaml:"containerPort"`
Requests Requests `yaml: "requests"`
Limits Limits `yaml: "limits"`
}
type Requests struct {
CPU string `yaml: "cpu"`
MEMORY string `yaml: "memory"`
}
type Limits struct {
CPU string `yaml: "cpu"`
MEMORY string `yaml: "memory"`
}
func main() {
var c KafkaCluster
//读取yaml配置文件, 将yaml配置文件，转换struct类型
conf := c.getConf()
//将对象，转换成json格式
data, err := json.Marshal(conf)
if err != nil {
fmt.Println("err:\t", err.Error())
return
}
//最终以json格式，输出
fmt.Println("data:\t", string(data))
}
//读取Yaml配置文件,
//并转换成conf对象 struct结构
func (kafkaCluster *KafkaCluster) getConf() *KafkaCluster {
//应该是 绝对地址
yamlFile, err := ioutil.ReadFile("E:\\Program\\go2\\goPath\\src\\xingej-go\\xingej-go\\xingej-go666\\lib\\yaml\\sparkConfig.yaml")
if err != nil {
fmt.Println(err.Error())
}
//err = yaml.Unmarshal(yamlFile, kafkaCluster)
err = yaml.UnmarshalStrict(yamlFile, kafkaCluster)
if err != nil {
fmt.Println(err.Error())
}
return kafkaCluster
}
2.3、运行结果：
data: {"ApiVersion":"v1","Kind":"KafkaCluster2","Metadata":{"Name":"kafka-operator","Labels":{"config1":{"Address":"kafka-operator-labels-01","Id":"kafka-operator-labels-02","Name":"mysql-example-cluster-master","NodeName":"172.16.91.21","Role":"master"},"config2":{"Address":"kafka-operator-labels-01","Id":"kafka-operator-labels-02","Name":"mysql-example-cluster-slave","NodeName":"172.16.91.110","Role":"slave"}}},"Spec":{"Replicas":1,"Name":"kafka-controller","Image":"172.16.26.4:5000/nginx","Ports":8088,"Conditions":[{"ContainerPort":"8080","Requests":{"CPU":"0.25","MEMORY":"512Mi"},"Limits":{"CPU":"0.25","MEMORY":"1Gi"}},{"ContainerPort":"9090","Requests":{"CPU":"0.33","MEMORY":"333Mi"},"Limits":{"CPU":"0.55","MEMORY":"5Gi"}}]}}==注意：==
yaml配置文件里，如果属性里存在大写的话，定义对应的属性时，一定不能有空格，可以参考上面例子中NodeServer里的说明 3 例子3，读取yaml配置文件中的某一个属性
3.1、 配置文件的内容：
apiVersion: v1
Kind: KafkaCluster3.2、代码如下：
//测试读取yaml文件的
package main
import (
"fmt"
"github.com/kylelemons/go-gypsy/yaml"
)
func main() {
file, err := yaml.ReadFile("E:\\Program\\go2\\goPath\\src\\xingej-go\\xingej-go\\xingej-go666\\lib\\yaml\\nginx")
if err != nil {
panic(err.Error())
}
apiVersion, error := file.Get("apiVersion")
if error != nil {
panic(error.Error())
}
fmt.Println("=apiVersion===:\t", apiVersion)
}
3.3、运行结果 ：
=apiVersion===: v1 4. 说明
例子3中用到的yaml解析包跟前面两个例子不是同一个。
"gopkg.in/yaml.v2"
"github.com/kylelemons/go-gypsy/yaml"
例子1，例子2 是整体读取Yaml配置文件，转换成其他格式
例子3，是读取yaml配置里的某一个属性，
因此，两者的使用场景是不一样的转载于:https://blog.51cto.com/xingej/2115258