It invokes the local go command to answer requests.
The default cacheDir is GOPATH, you can set it up by yourself according to the situation.

git clone https://github.com/goproxyio/goproxy.git
cd goproxy
make

./bin/goproxy -listen=0.0.0.0:80 -cacheDir=/tmp/test

./bin/goproxy -listen=0.0.0.0:80 -proxy https://goproxy.io

                                         direct
                      +----------------------------------> private repo
                      |
                 match|pattern
                      |
                  +---+---+           +----------+
go get  +-------> |goproxy| +-------> |goproxy.io| +---> golang.org/x/net
                  +-------+           +----------+
                 router mode           proxy mode

./bin/goproxy -listen=0.0.0.0:80 -cacheDir=/tmp/test -proxy https://goproxy.io -exclude "*.corp.example.com,rsc.io/private"

docker run -d -p80:8081 goproxy/goproxy

docker run -d -p80:8081 -v cacheDir:/go goproxy/goproxy

docker-compose up