go get unrecognized import path "golang.org/x/net"

報錯信息

$ go get golang.org/x/net/websocket
unrecognized import path "golang.org/x/net/websocket": https fetch: Get "https://golang.org/x/net/websocket?go-get=1": dial tcp 216.239.37.1:443: connectex: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.

go get 中撞牆，即便掛着vpn仍然無法下載

嘗試過 go get層面增加代理也沒能解決（本身代理地址是阿里雲鏡像）

go 1.11版本新增了 GOPROXY 環境變量，go get會根據這個環境變量來決定去哪裏取引入庫的代碼

$ export GOPROXY=https://goproxy.io

最終解決方案

$mkdir -p $GOPATH/src/golang.org/x/
$cd $GOPATH/src/golang.org/x/
$git clone https://github.com/golang/net.git net 
$go install net

手動克隆庫到本地環境
再執行go get 安裝（如： go get golang.org/x/net/websocket）
即可安裝成功