go mod详细使用教程

### 卸载旧版本，删除对应文件
brew uninstall -f go

### 更新一下brew

brew update

### 安装go
brew install go

go version go1.14.1 darwin/amd64

go env -w GOBIN=/Users/youdi/go/bin
go env -w GO111MODULE=on
go env -w GOPROXY=https://goproxy.cn,direct // 使用七牛云的

GO111MODULE="on"
GOARCH="amd64"
GOBIN="/Users/youdi/go/bin"
GOCACHE="/Users/youdi/Library/Caches/go-build"
GOENV="/Users/youdi/Library/Application Support/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOINSECURE=""
GONOPROXY=""
GONOSUMDB=""
GOOS="darwin"
GOPATH="/Users/youdi/go"
GOPRIVATE=""
GOPROXY="Https://goproxy.cn,direct"
GOROOT="/usr/local/go"
GOSUMDB="off"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go/pkg/tool/darwin_amd64"
GCCGO="gccgo"
AR="ar"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD="/dev/null"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/8m/v_1j4dgs7rzgqq4p_4_8k_nr0000gn/T/go-build221113671=/tmp/go-build -gno-record-gcc-switches -fno-common"

GO111MODULE=on
GOBIN=/Users/youdi/go/bin
GOPROXY=https://goproxy.cn,direct
GOSUMDB=off

Go mod provides access to operations on modules.

Note that support for modules is built into all the go commands,
not just 'go mod'. For example, day-to-day adding, removing, upgrading,
and downgrading of dependencies should be done using 'go get'.
See 'go help modules' for an overview of module functionality.

Usage:

    go mod <command> [arguments]

The commands are:

    download    download modules to local cache
    edit        edit go.mod from tools or scripts
    graph       print module requirement graph
    init        initialize new module in current directory
    tidy        add missing and remove unused modules
    vendor      make vendored copy of dependencies
    verify      verify dependencies have expected content
    why         explain why packages or modules are needed

Use "go help mod <command>" for more infORMation about a command.

mkdir Gone
cd Gone
go mod init Gone

module Gone

go 1.14

package main

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

func main() {
    r := gin.Default()
    r.GET("/ping", func(c *gin.Context) {
        c.JSON(200, gin.H{
            "message": "pong",
        })
    })
    r.Run() // listen and serve on 0.0.0.0:8080 (for windows "localhost:8080")
}

module Gone

go 1.14

require github.com/gin-gonic/gin v1.6.3

/Users/youdi/go/pkg/mod/github.com/gin-gonic/gin@v1.6.3

replace (
    golang.org/x/crypto v0.0.0-20190313024323-a1f597ede03a => github.com/golang/crypto v0.0.0-20190313024323-a1f597ede03a
)

$mkdir gomodone
$cd gomodone

package gomodone

import "fmt" 

// say Hi to someone
func SayHi(name string) string {
   return fmt.Sprintf("Hi, %s", name)
}

$ go mod init github.com/jacksonyoudi/gomodone
go: creating new go.mod: module github.com/jacksonyoudi/gomodone

github.com/jacksonyoudi/gomodone
go 1.14

$git init
$vim .gitiiignore
$git commit -am "init"
// github创建对应的repo
$git remote add origin git@github.com:jacksonyoudi/gomodone.git
$git push -u origin master

go get github.com/jacksonyoudi/gomodone

gomodone@v0.0.0-20200517004046-ee882713fd1e

git tag v1.0.0
git push --tags

$git checkout -b v1
$git push -u origin v1

$mkdir Gone
$cd Gone
$vim main.go

package main

import (
    "fmt"
    "github.com/jacksonyoudi/gomodone"
)

func main() {
    fmt.Println(gomodone.SayHi("Roberto"))
}

go mod init Gone

module Gone

go 1.14

require (
    github.com/jacksonyoudi/gomodone v1.0.0
)

$go mod tidy
go: finding module for package github.com/jacksonyoudi/gomodone
go: found github.com/jacksonyoudi/gomodone in github.com/jacksonyoudi/gomodone v1.0.0

github.com/jacksonyoudi/gomodone v1.0.1 h1:jFd+qZlAB0R3zqrC9kwO8IgPrAdayMUS0rSHMDc/uG8=
github.com/jacksonyoudi/gomodone v1.0.1/go.mod h1:XWi+BLbuiuC2YM8Qz4yQzTSPtHt3T3hrlNN2pNlyA94=
github.com/jacksonyoudi/gomodone/v2 v2.0.0 h1:GpzGeXCx/Xv2ueiZJ8hEhFwLu7xjxLBjkOYSmg8Ya/w=
github.com/jacksonyoudi/gomodone/v2 v2.0.0/go.mod h1:L8uFPSZNHoAhpaePWUfKmGinjufYdw9c2i70xtBorSw=

// say Hi to someone
func SayHi(name string) string {
-       return fmt.Sprintf("Hi, %s", name)
+       return fmt.Sprintf("Hi, %s!", name)
}

$ git commit -m "Emphasize our friendliness" say.go
$ git tag v1.0.1
$ git push --tags origin v1

// 更新最新
$go get -u
$go get -u=patch
//指定包，指定版本
$go get github.com/jacksonyoudi/gomodone@v1.0.1

module Gone

go 1.14

require (
    github.com/jacksonyoudi/gomodone v1.0.1
)

package gomodone

import (
    "errors"
    "fmt"
)

// Hi returns a friendly greeting
// Hi returns a friendly greeting in language lang
func SayHi(name, lang string) (string, error) {
    switch lang {
    case "en":
        return fmt.Sprintf("Hi, %s!", name), nil
    case "pt":
        return fmt.Sprintf("Oi, %s!", name), nil
    case "es":
        return fmt.Sprintf("¡Hola, %s!", name), nil
    case "fr":
        return fmt.Sprintf("Bonjour, %s!", name), nil
    default:
        return "", errors.New("unknown language")
    }
}

module github.com/jacksonyoudi/gomodone/v2

go 1.14

$ git commit say.go -m "Change Hi to allow multilang"
$ git checkout -b v2 # 用于v2版本，后续修复v2
$ git commit go.mod -m "Bump version to v2"
$ git tag v2.0.0
$ git push --tags origin v2 

package main

import (
    "fmt"
    "github.com/jacksonyoudi/gomodone/v2"
)

func main() {
    g, err := gomodone.SayHi("Roberto", "pt")
    if err != nil {
        panic(err)
    }
    fmt.Println(g)
}

go: finding module for package github.com/jacksonyoudi/gomodone/v2
go: downloading github.com/jacksonyoudi/gomodone/v2 v2.0.0
go: found github.com/jacksonyoudi/gomodone/v2 in github.com/jacksonyoudi/gomodone/v2 v2.0.0

package main

import (
    "fmt"
    "github.com/jacksonyoudi/gomodone"
    mv2 "github.com/jacksonyoudi/gomodone/v2"
)

func main() {
    g, err := mv2.SayHi("Roberto", "pt")
    if err != nil {
        panic(err)
    }
    fmt.Println(g)

    fmt.Println(gomodone.SayHi("Roberto"))
}

$go vendor

$ go build -mod vendor