You’ve probably just tried to initialise a new Go module, and received the following error:
go mod init: modules disabled by GO111MODULE=off; see 'go help modules'
This usually happens after running a command like:
go mod init github.com/<user>/<repo>
What is GO111MODULE?
From Go version 1.11, the way to deal with modules was revamped.
Beforehand, it was required that you place all your Go code under a $GOPATH.
Which many Go developers didn’t much like, as it seemed chaotic at best.
Also, having a package management/module management solution is so much more productive, and manageable.
Solution 1:
You could always just go and change the off to on as an environment variable and you’d be good to go!
export GO111MODULE="on"
This would result in a successful module being created after trying the previous command that resulted in the error in the first place:
go: creating new go.mod: module github.com/<user>/<repo>
If you’re on Windows, simply replace export with set.
Solution 2:
For a more direct way of achieving the same as Solution 1 above, use Go directly to update the environment variable:
go env -w GO111MODULE=on
Solution 3:
It’s quite possible that you have a go.mod file under your $GOPATH/go.mod location.
You should remove this file.
Remember that since you are using Go 1.11 or newer, you can use the go get command outside of $GOPATH, so it’s no longer required.