Gin 5

[root@h160 ~]# hostnamectl 
   Static hostname: h160
         Icon name: computer-vm
           Chassis: vm
        Machine ID: d46f9440d4be429ea66b726977adf233
           Boot ID: a0fc6a1b4f124e39a27866d4df0701fa
    Virtualization: kvm
  Operating System: CentOS Linux 7 (Core)
       CPE OS Name: cpe:/o:centos:centos:7
            Kernel: Linux 3.10.0-862.2.3.el7.x86_64
      Architecture: x86-64
[root@h160 ~]# ip a 
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 52:54:00:c9:c7:04 brd ff:ff:ff:ff:ff:ff
    inet 10.0.2.15/24 brd 10.0.2.255 scope global noprefixroute dynamic eth0
       valid_lft 84363sec preferred_lft 84363sec
    inet6 fe80::5054:ff:fec9:c704/64 scope link 
       valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 08:00:27:48:f4:2c brd ff:ff:ff:ff:ff:ff
    inet 192.168.56.160/24 brd 192.168.56.255 scope global noprefixroute eth1
       valid_lft forever preferred_lft forever
    inet6 fe80::a00:27ff:fe48:f42c/64 scope link 
       valid_lft forever preferred_lft forever
[root@h160 ~]# go version
go version go1.9.4 linux/amd64
[root@h160 ~]#

[vagrant@h160 ~]$ echo $GOPATH
/vagrant/go
[vagrant@h160 ~]$ cd $GOPATH
[vagrant@h160 go]$ pwd
/vagrant/go
[vagrant@h160 go]$ 

package main  //指明此包为 main 包

import "github.com/gin-gonic/gin" //导入 gin 包
import "fmt" // 导入 fmt 可以进行格式化输出

func main() {
	r := gin.Default()  // 使用 gin.Default() 方法生成一个引擎实例,这个实例默认情况下已经将 Logger Recovery 进行了装载
	r.POST("/form", func(c *gin.Context) {
		//DefaultPostForm returns the specified key from a POST urlencoded form or multipart form when it exists, otherwise it returns the specified defaultValue string
		tag := c.DefaultPostForm("tag", "alert")//func (c *Context) DefaultPostForm(key, defaultValue string) string ,第二个参数为默认值
		//func (c *Context) PostForm(key string) string
		msg := c.PostForm("msg")
		title := c.PostForm("title")
		fmt.Printf("tag is %s, msg is %s, title is %s\n", tag, msg, title)
	})
	r.Run(":8080") //在 0.0.0.0:8080 上启监听
}

[vagrant@h160 go]$ go run hello.go 
[GIN-debug] [WARNING] Now Gin requires Go 1.6 or later and Go 1.7 will be required soon.

[GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.

[GIN-debug] [WARNING] Running in "debug" mode. Switch to "release" mode in production.
 - using env:	export GIN_MODE=release
 - using code:	gin.SetMode(gin.ReleaseMode)

[GIN-debug] POST   /form                     --> main.main.func1 (3 handlers)
[GIN-debug] Listening and serving HTTP on :8080
tag is t1, msg is m1, title is test
[GIN] 2018/07/06 - 16:57:48 | 200 |      148.11µs |  192.168.56.105 | POST     /form
tag is alert, msg is m1, title is test
[GIN] 2018/07/06 - 16:57:59 | 200 |      66.528µs |  192.168.56.105 | POST     /form
tag is , msg is m1, title is test
[GIN] 2018/07/06 - 16:58:04 | 200 |      57.533µs |  192.168.56.105 | POST     /form
tag is , msg is , title is test
[GIN] 2018/07/06 - 16:58:12 | 200 |       77.04µs |  192.168.56.105 | POST     /form
tag is , msg is , title is 
[GIN] 2018/07/06 - 16:58:18 | 200 |      56.704µs |  192.168.56.105 | POST     /form
tag is , msg is , title is 
[GIN] 2018/07/06 - 16:58:23 | 200 |      64.421µs |  192.168.56.105 | POST     /form
tag is alert, msg is , title is 
[GIN] 2018/07/06 - 16:58:29 | 200 |      73.434µs |  192.168.56.105 | POST     /form
...
...
...

[vagrant@h105 ~]$ curl -XPOST 192.168.56.160:8080/form -d 'tag=t1&msg=m1&title=test'
[vagrant@h105 ~]$ curl -XPOST 192.168.56.160:8080/form -d 'msg=m1&title=test'
[vagrant@h105 ~]$ curl -XPOST 192.168.56.160:8080/form -d 'tag=&msg=m1&title=test'
[vagrant@h105 ~]$ curl -XPOST 192.168.56.160:8080/form -d 'tag=&msg=&title=test'
[vagrant@h105 ~]$ curl -XPOST 192.168.56.160:8080/form -d 'tag=&msg=&title='
[vagrant@h105 ~]$ curl -XPOST 192.168.56.160:8080/form -d 'tag='
[vagrant@h105 ~]$ curl -XPOST 192.168.56.160:8080/form -d ''
[vagrant@h105 ~]$