go get使用goproxy.cn仍然报错connectex: A connection attempt failed的解决方法

执行

go get -v golang.org/x/tools/gopls

报错：

package golang.org/x/tools/gopls: unrecognized import path "golang.org/x/tools/gopls": https fetch: Get "https://golang.org/x/tools/gopls?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.

经过一番查找所有的方法都称只要执行

go env -w GOPROXY=https://goproxy.cn

 或加上direct执行

go env -w GOPROXY=https://goproxy.cn,direct

或执行

go env -w GOSUMDB=off

把GOSUMDB关掉或设置Git的HTTP和HTTPS的代理的方法或设置为阿里云aliyun源，全部无效。最终在Goproxy China首页找到真正的解决方法：执行

go env -w GO111MODULE=on
go env -w GOPROXY=https://goproxy.cn,direct

即可解决 。

注：可通过执行

go env

命令查看所有的go环境变量。

再次执行

go get -v golang.org/x/tools/gopls

输出：

go: downloading golang.org/x/tools v0.1.0
go: downloading golang.org/x/tools/gopls v0.6.5
go: golang.org/x/tools/gopls upgrade => v0.6.5
go: downloading golang.org/x/tools v0.1.1-0.20210201201750-4d4ee958a9b7
go: downloading mvdan.cc/xurls/v2 v2.2.0
go: downloading mvdan.cc/gofumpt v0.1.0
go: downloading golang.org/x/mod v0.4.0
go: downloading golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1
go: downloading honnef.co/go/tools v0.0.1-2020.1.6
go: downloading golang.org/x/sys v0.0.0-20210119212857-b64e53b001e4
go: downloading golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9
go: downloading github.com/google/go-cmp v0.5.4
go: downloading github.com/sergi/go-diff v1.1.0
go: downloading github.com/BurntSushi/toml v0.3.1
golang.org/x/mod/semver
golang.org/x/xerrors/internal
honnef.co/go/tools/arg
honnef.co/go/tools/deprecated
github.com/google/go-cmp/cmp/internal/flags
golang.org/x/tools/internal/xcontext
golang.org/x/tools/go/ast/astutil
github.com/sergi/go-diff/diffmatchpatch
golang.org/x/tools/internal/lsp/fuzzy
golang.org/x/tools/internal/span
golang.org/x/mod/internal/lazyregexp
golang.org/x/xerrors
golang.org/x/tools/go/analysis/passes/internal/analysisutil
golang.org/x/tools/internal/analysisinternal
golang.org/x/tools/go/ast/inspector
golang.org/x/tools/go/types/typeutil
golang.org/x/tools/internal/lsp/diff
golang.org/x/tools/go/cfg
golang.org/x/mod/module
golang.org/x/tools/internal/event/label
golang.org/x/tools/go/analysis
golang.org/x/sys/execabs
golang.org/x/tools/internal/fastwalk
golang.org/x/tools/internal/event/keys
golang.org/x/mod/modfile
golang.org/x/tools/internal/lsp/diff/myers
golang.org/x/tools/go/analysis/passes/asmdecl
golang.org/x/tools/go/analysis/passes/inspect
golang.org/x/tools/go/analysis/passes/buildtag
golang.org/x/tools/go/analysis/passes/cgocall
golang.org/x/tools/go/analysis/passes/assign
golang.org/x/tools/go/analysis/passes/atomic
golang.org/x/tools/go/analysis/passes/atomicalign
golang.org/x/tools/go/analysis/passes/bools
golang.org/x/tools/go/analysis/passes/composite
golang.org/x/tools/go/analysis/passes/copylock
golang.org/x/tools/go/analysis/passes/deepequalerrors
golang.org/x/tools/go/analysis/passes/errorsas
golang.org/x/tools/go/analysis/passes/fieldalignment
golang.org/x/tools/go/analysis/passes/httpresponse
golang.org/x/tools/go/analysis/passes/ifaceassert
golang.org/x/tools/go/analysis/passes/loopclosure
golang.org/x/tools/go/analysis/passes/ctrlflow
golang.org/x/tools/go/analysis/passes/nilfunc
golang.org/x/tools/go/analysis/passes/printf
golang.org/x/tools/go/analysis/passes/shadow
golang.org/x/tools/go/analysis/passes/shift
golang.org/x/tools/go/analysis/passes/sortslice
golang.org/x/tools/go/analysis/passes/stdmethods
golang.org/x/tools/go/analysis/passes/stringintconv
golang.org/x/tools/go/analysis/passes/lostcancel
golang.org/x/tools/go/analysis/passes/structtag
golang.org/x/tools/go/analysis/passes/testinggoroutine
golang.org/x/tools/go/analysis/passes/tests
golang.org/x/tools/go/analysis/passes/unmarshal
golang.org/x/tools/go/analysis/passes/unreachable
golang.org/x/tools/go/analysis/passes/unsafeptr
golang.org/x/tools/go/analysis/passes/unusedresult
golang.org/x/tools/internal/event/core
golang.org/x/tools/internal/gopathwalk
golang.org/x/tools/internal/lsp/analysis/fillreturns
golang.org/x/tools/internal/lsp/analysis/fillstruct
golang.org/x/tools/internal/lsp/analysis/nonewvars
golang.org/x/tools/internal/lsp/analysis/noresultvalues
golang.org/x/tools/internal/event
golang.org/x/tools/internal/gocommand
golang.org/x/tools/internal/lsp/analysis/simplifycompositelit
golang.org/x/tools/internal/lsp/analysis/simplifyslice
golang.org/x/tools/internal/lsp/analysis/undeclaredname
golang.org/x/tools/internal/lsp/analysis/simplifyrange
golang.org/x/tools/internal/lsp/analysis/unusedparams
golang.org/x/tools/internal/lsp/debug/tag
golang.org/x/tools/internal/imports
golang.org/x/tools/internal/event/export
golang.org/x/tools/refactor/satisfy
honnef.co/go/tools/go/types/typeutil
honnef.co/go/tools/ir
golang.org/x/tools/internal/jsonrpc2
golang.org/x/tools/go/internal/gcimporter
golang.org/x/tools/go/internal/packagesdriver
golang.org/x/tools/internal/packagesinternal
golang.org/x/tools/internal/typesinternal
golang.org/x/tools/go/types/objectpath
golang.org/x/tools/internal/lsp/protocol
golang.org/x/tools/go/gcexportdata
honnef.co/go/tools/functions
github.com/BurntSushi/toml
honnef.co/go/tools/internal/passes/buildir
golang.org/x/tools/go/packages
honnef.co/go/tools/internal/robustio
honnef.co/go/tools/facts
golang.org/x/tools/go/buildutil
golang.org/x/tools/internal/lsp/source
honnef.co/go/tools/version
honnef.co/go/tools/internal/renameio
honnef.co/go/tools/loader
honnef.co/go/tools/config
golang.org/x/tools/go/internal/cgo
honnef.co/go/tools/internal/cache
honnef.co/go/tools/printf
golang.org/x/tools/go/loader
github.com/google/go-cmp/cmp/internal/diff
github.com/google/go-cmp/cmp/internal/function
github.com/google/go-cmp/cmp/internal/value
mvdan.cc/xurls/v2
golang.org/x/tools/internal/fakenet
honnef.co/go/tools/ir/irutil
golang.org/x/sync/errgroup
github.com/google/go-cmp/cmp
honnef.co/go/tools/lint
golang.org/x/tools/internal/lsp/debug/log
golang.org/x/tools/internal/memoize
golang.org/x/tools/internal/event/export/metric
golang.org/x/tools/internal/event/export/ocagent/wire
golang.org/x/tools/internal/lsp/mod
golang.org/x/tools/internal/lsp/snippet
golang.org/x/tools/internal/lsp/cache
golang.org/x/tools/internal/event/export/ocagent
golang.org/x/tools/internal/event/export/prometheus
honnef.co/go/tools/code
honnef.co/go/tools/pattern
honnef.co/go/tools/lint/lintutil/format
honnef.co/go/tools/report
mvdan.cc/gofumpt/format
golang.org/x/tools/internal/lsp/source/completion
honnef.co/go/tools/edit
honnef.co/go/tools/lint/lintdsl
golang.org/x/tools/internal/lsp/browser
honnef.co/go/tools/lint/lintutil
golang.org/x/tools/internal/tool
golang.org/x/tools/internal/lsp/debug
honnef.co/go/tools/internal/sharedcheck
honnef.co/go/tools/stylecheck
golang.org/x/tools/internal/lsp
honnef.co/go/tools/simple
honnef.co/go/tools/staticcheck
golang.org/x/tools/internal/lsp/lsprpc
golang.org/x/tools/internal/lsp/cmd
golang.org/x/tools/gopls/internal/hooks
golang.org/x/tools/gopls

成功。