Gin - part 1

November 04, 2019 Golang Gin

前言

因為想玩玩golang的gin，所以就來玩玩囉!
官方Github

安裝

λ go get -u github.com/gin-gonic/gin

Demo

// demo.go
package main

import (
	"net/http"

	"github.com/gin-gonic/gin"
)

func main() {
	engine := gin.Default()
	engine.Any("/", WebRoot)
	engine.Run(":8081")
}

func WebRoot(context *gin.Context) {
	context.String(http.StatusOK, "Hello world!")
}

λ go run demo.go
[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] GET    /                         --> main.WebRoot (3 handlers)
[GIN-debug] POST   /                         --> main.WebRoot (3 handlers)
[GIN-debug] PUT    /                         --> main.WebRoot (3 handlers)
[GIN-debug] PATCH  /                         --> main.WebRoot (3 handlers)
[GIN-debug] HEAD   /                         --> main.WebRoot (3 handlers)
[GIN-debug] OPTIONS /                         --> main.WebRoot (3 handlers)
[GIN-debug] DELETE /                         --> main.WebRoot (3 handlers)
[GIN-debug] CONNECT /                         --> main.WebRoot (3 handlers)
[GIN-debug] TRACE  /                         --> main.WebRoot (3 handlers)
[GIN-debug] Listening and serving HTTP on :8081
[GIN] 2019/11/05 - 01:00:56 | 200 |            0s |       127.0.0.1 | GET      /
[GIN] 2019/11/05 - 01:00:56 | 404 |            0s |       127.0.0.1 | GET      /favicon.ico

Router

path parameter

package main

import (
	"net/http"

	"github.com/gin-gonic/gin"
)

func main() {
	engine := gin.Default()
	engine.GET("/:name", getting)
	engine.Run(":8081")
}

func getting(context *gin.Context) {
	name := context.Param("name")
	context.String(http.StatusOK, "Hello %s!", name)
}

get

package main

import (
	"net/http"

	"github.com/gin-gonic/gin"
)

func main() {
	engine := gin.Default()
	// url: /welcome/{name}?age=5&birthday=1000/01/01
	engine.GET("/welcome/:name", getting)
	engine.Run(":8081")
}

func getting(context *gin.Context) {
	name := context.Param("name")
	age := context.DefaultQuery("age", "0")
	birthday := context.Query("birthday")
	context.String(http.StatusOK, "Hello %s!\nage: %s\nBirthday: %s\n", name, age, birthday)
}

struct

package main

import (
	"net/http"

	"github.com/gin-gonic/gin"
)

type Person struct {
	Name     string `form:"name"`
	Age      int    `form:"age"`
	Birthday string `form:"birthday"`
}

func main() {
	engine := gin.Default()
	// url: /welcome/{name}?age=5&birthday=1000/01/01
	engine.GET("/welcome/:name", getting)
	engine.Run(":8081")
}

func getting(context *gin.Context) {
	var person Person
	name := context.Param("name")
	if context.ShouldBindQuery(&person) == nil {
		context.String(http.StatusOK, "Hello %s!\nage: %d\nBirthday: %s\n", name, person.Age, person.Birthday)
	} else {
		context.String(400, "Bad Request")
	}
}

post

form post

package main

import (
	"net/http"

	"github.com/gin-gonic/gin"
)

func main() {
	engine := gin.Default()
	engine.POST("/form_post", form_post)
	engine.Run(":8081")
}

func form_post(context *gin.Context) {
	name := context.PostForm("name")
	age := context.DefaultPostForm("age", "0")
	birthday := context.PostForm("birthday")
	context.String(http.StatusOK, "Hello %s!\nage: %s\nBirthday: %s\n", name, age, birthday)
}

λ curl -X POST http://127.0.0.1:8081/form_post -F "name=haha" -F "age=5" -F "birthday=1000/01/01"
Hello haha!
age: 5
Birthday: 1000/01/01

struct

package main

import (
	"net/http"

	"github.com/gin-gonic/gin"
)

type Person struct {
	Name     string `form:"name"`
	Age      int    `form:"age"`
	Birthday string `form:"birthday"`
}

func main() {
	engine := gin.Default()
	engine.POST("/form_post", form_post)
	engine.Run(":8081")
}

func form_post(context *gin.Context) {
	var person Person
	if context.ShouldBind(&person) == nil {
		context.String(http.StatusOK, "Hello %s!\nage: %d\nBirthday: %s\n", person.Name, person.Age, person.Birthday)
	} else {
		context.String(400, "Bad Request")
	}
}

λ curl -X POST http://127.0.0.1:8081/form_post -F "name=haha" -F "age=5" -F "birthday=1000/01/01"
Hello haha!
age: 5
Birthday: 1000/01/01

json post

package main

import (
	"log"

	"github.com/gin-gonic/gin"
)

func main() {
	engine := gin.Default()
	engine.POST("/json_post", json_post)
	engine.Run(":8081")
}

func json_post(context *gin.Context) {
	rawData, err := context.GetRawData()
	if err != nil {
		log.Fatalln(err)
	}
	log.Println(string(rawData))
	context.String(200, "ok")
}

λ curl -X POST http://127.0.0.1:8081/json_post -H "content-type: application/json" -d "{ 'name': 'haha', 'age': 5, 'birthday': '1000/01/01'}"
ok

2019/11/06 00:36:26 { 'name': 'haha', 'age': 5, 'birthday': '1000/01/01'}
[GIN] 2019/11/06 - 00:36:26 | 200 |            0s |       127.0.0.1 | POST     /json_post

struct

package main

import (
	"net/http"

	"github.com/gin-gonic/gin"
)

type Person struct {
	Name     string `json:"name" binding:"required"`
	Age      int    `json:"age" binding:"required"`
	Birthday string `json:"birthday" binding:"required"`
}

func main() {
	engine := gin.Default()
	engine.POST("/json_post", json_post)
	engine.Run(":8081")
}

func json_post(context *gin.Context) {
	var person Person
	if err := context.ShouldBindJSON(&person); err == nil {
		context.String(http.StatusOK, "Hello %s!\nage: %d\nBirthday: %s\n", person.Name, person.Age, person.Birthday)
	} else {
		context.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
	}
}

Combine json and form post

package main

import (
	"net/http"

	"github.com/gin-gonic/gin"
)

type Person struct {
	Name     string `form:"name" json:"name" binding:"required"`
	Age      int    `form:"age" json:"age" binding:"required"`
	Birthday string `form:"birthday" json:"birthday" binding:"required"`
}

func main() {
	engine := gin.Default()
	engine.POST("/form_post", form_post)
	engine.POST("/json_post", json_post)
	engine.Run(":8081")
}

func form_post(context *gin.Context) {
	var person Person
	if err := context.ShouldBind(&person); err == nil {
		context.String(http.StatusOK, "form post\nHello %s!\nage: %d\nBirthday: %s\n", person.Name, person.Age, person.Birthday)
	} else {
		context.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
	}
}

func json_post(context *gin.Context) {
	var person Person
	if err := context.ShouldBindJSON(&person); err == nil {
		context.String(http.StatusOK, "json post\nHello %s!\nage: %d\nBirthday: %s\n", person.Name, person.Age, person.Birthday)
	} else {
		context.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
	}
}

Group

package main

import (
	"net/http"

	"github.com/gin-gonic/gin"
)

type Person struct {
	Name     string `form:"name" json:"name" binding:"required"`
	Age      int    `form:"age" json:"age" binding:"required"`
	Birthday string `form:"birthday" json:"birthday" binding:"required"`
}

func main() {
	router := gin.Default()
	v1 := router.Group("/v1")
	{
		v1.POST("/welcome", form_post)
	}
	v2 := router.Group("/v2")
	{
		v2.POST("/welcome", json_post)
	}
	router.Run(":8081")
}

func form_post(context *gin.Context) {
	var person Person
	if err := context.ShouldBind(&person); err == nil {
		context.String(http.StatusOK, "form post\nHello %s!\nage: %d\nBirthday: %s\n", person.Name, person.Age, person.Birthday)
	} else {
		context.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
	}
}

func json_post(context *gin.Context) {
	var person Person
	if err := context.ShouldBindJSON(&person); err == nil {
		context.String(http.StatusOK, "json post\nHello %s!\nage: %d\nBirthday: %s\n", person.Name, person.Age, person.Birthday)
	} else {
		context.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
	}
}

Part1就先到這囉~~