Debugging Windows 10 Docker not exposing ports

Dockerfile

FROM golang:1.13-nanoserver-1809

COPY main.go c:/main.go

RUN go build -o c:\\webserver.exe c:\\main.go

CMD ["c:\\webserver.exe"]

gistfile1.txt

Working
Microsoft Windows [Version 10.0.18362.592]
Docker 2.1.04





docker build -t webserver .
docker run -p8080:8080 webserver

main.go

package main

import (
        "fmt"
        "net/http"
        "os"
        "strconv"
)

const DEFAULT_PORT = 8080

func handler(w http.ResponseWriter, r *http.Request) {
        fmt.Fprintf(w, "Hi there %s!", r.URL.Path[1:])
}

func main() {
        var port int = DEFAULT_PORT
        var err error

        sport := os.Getenv("PORT")

        if sport != "" {
                port, err = strconv.Atoi(sport)

                if err != nil {
                        panic(err)
                }
        }

        fmt.Printf("Running on :%d", port)

        http.HandleFunc("/", handler)
        http.ListenAndServe(fmt.Sprintf(":%d", port), nil)
}