GO111MODULE=on/off
GO111MODULE
GO111MODULEgo-cmpGOPATH
GOPATH
$GOPATH
  bin/                       # Directory where executable binaries are stored
  src/                       # Directory where Go source files of the dependent packages are stored
    github.com/google/go-cmp/
      ...
  pkg/                       # Directory where compiled Go object files are stored
    ...

其中：

binsrcpkg
go get xxx$GOPATH/srcGO111MODULE=off$GOPATHgo-cmp
$ docker run -it golang:1.13 /bin/bash
$ GO111MODULE=off go get github.com/google/go-cmp/cmp
$ tree -d -L 5 $GOPATH   # assume tree is installed
/go
|-- bin
|-- pkg/linux_amd64/github.com/google/go-cmp
`-- src/github.com/google/go-cmp/cmp
tree

根据 Go 1.11 发版时的声明：

This release adds preliminary support for a new concept called “modules,” an alternative to GOPATH with integrated support for versioning and package distribution.
— 
modulego module init xxx$GOPATH
$ GO111MODULE=on go get github.com/google/go-cmp/cmp
$ tree -d -L 5 $GOPATH
/go
`-- pkg
    |-- mod
    |   |-- cache
    |   |   `-- download
    |   |       |-- github.com
    |   |       |-- golang.org
    |   |       `-- sumdb
    |   `-- github.com
    |       `-- google
    |           `-- go-cmp@v0.4.0
    `-- sumdb
        `-- sum.golang.org
module

Module

$GOPATH$GOPATH$GOPATH
$GOPATHtestproject

main.go:

// main.go
package main

func main() {
        TestFunc()
}

test_func.go:

// test_func.go
package main

import "k8s.io/klog"

func TestFunc() {
        klog.Infoln("Hello Go Modules!")
}

尝试编译并运行，发现能正常跑起来：

/anywhere/outside/gopath/testproject $ GO111MODULE=off go get k8s.io/klog
/anywhere/outside/gopath/testproject $ GO111MODULE=off go run .
I0404 14:58:55.589292    1445 test_func.go:6] Hello Go Modules!
main$GOPATH

将打印信息的方法移到单独模块中，目录结构变成了：

$ tree /anywhere/outside/gopath/testproject
/anywhere/outside/gopath/testproject
|-- main.go
`-- test
    `-- func.go

test/func.go:

// test/func.go

package test

import "k8s.io/klog"

func TestFunc() {
        klog.Infoln("Hello Go Modules!")
}

同时更新 main.go 中的调用：

// main.go

package main

import "test"

func main() {
        XXX.TestFunc()
}

尝试运行会有如下报错：

$ GO111MODULE=off go run .
main.go:3:8: cannot find package "test" in any of:
	/usr/local/go/src/test (from $GOROOT)
	/go/src/test (from $GOPATH)
root@7d47e56e5fcc:/wy/testproject# vi main.go
main.gotestmoduleGO111MODULE=off$GOPATH
$GOPATHGO111MODULE=off
$GOPATH
$ tree $GOPATH/src/insujang.github.io
/go/src/insujang.github.io
`-- testproject
    |-- main.go
    `-- test
        `-- func.go
main.go
import "insujang.github.io/testproject/test"

再次运行便可以成功了：

$ $GOPATH/src/insujang.github.io/testproject $ GO111MODULE=off go run .
I0404 15:09:40.239612    2034 func.go:6] Hello Go Modules!

Module 的使用

除上回退到旧版依赖管理方式上，还可以使用 module 来解决上面的问题。

首先将项目初始化成 module:

$ /anywhere/outside/gopath/testproject $ go mod init insujang.github.io/testproject
/anywhere/outside/gopath/testproject $ GO111MODULE=on go run .
I0404 15:18:36.553399    2303 func.go:6] Hello Go Modules!
main.go
// main.go
package main

import "insujang.github.io/testproject/test"

func main() {
        test.TestFunc()
}
$GOPATH

项目正常运行：

$ /anywhere/outside/gopath/testproject $ GO111MODULE=off go run .
main.go:3:8: cannot find package "insujang.github.io/testproject/test" in any of:
        /usr/local/go/src/insujang.github.io/testproject/test (from $GOROOT)
        /go/src/insujang.github.io/testproject/test (from $GOPATH)

GO111MODULE 的默认值

GO111MODULEauto



go.mod$GOPATH

相关资源