在Go中创建了非常基本的Web应用程序

package main

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

func hostHandler(w http.ResponseWriter, r *http.Request){
    name, err :=os.Hostname()

    if err != nil {
           panic(err)
        }

        fmt.Fprintf(w, "<h1>HOSTNAME: %s</h1><br>",name)
        fmt.Fprintf(w, "<h1>ENVIRONMENT VARS: </h1><br>")
        fmt.Fprintf(w, "<ul>")

        for _, evar := range os.Environ(){
            fmt.Fprintf(w, "<li>%s</li>",evar)
        }
        fmt.Fprintf(w, "</ul>")

}

func rootHandler(w http.ResponseWriter, r *http.Request){

    fmt.Fprintf(w, "<h1>Awesome site in Go!</h1><br>")
    fmt.Fprintf(w, "<a href='/host/'>Host info</a><br>")

}

func main() {

        http.HandleFunc("/", rootHandler)
        http.HandleFunc("/host/", hostHandler)
        http.ListenAndServe(":8080", nil)


}

Docker文件

FROM scratch
WORKDIR /home/ubuntu/go
COPY webapp /
EXPOSE 8080
CMD ["/webapp"]

映像构建成功

ubuntu@ip-172-31-32-125:~/go/src/hello$ docker build -t "webapp" .
Sending build context to Docker daemon  6.152MB
Step 1/5 : FROM scratch
 --->
Step 2/5 : WORKDIR /home/ubuntu/go
 ---> Using cache
 ---> 8810a06c58c7
Step 3/5 : COPY webapp /
 ---> Using cache
 ---> d75222363d3a
Step 4/5 : EXPOSE 8080
 ---> Using cache
 ---> 45de0853de8e
Step 5/5 : CMD ["/webapp"]
 ---> Using cache
 ---> e9f9031f3632
Successfully built e9f9031f3632
Successfully tagged webapp:latest

但是当我运行docker时，它的显示错误。

ubuntu@ip-172-31-32-125:~/go/src/hello$ docker run webapp
standard_init_linux.go:190: exec user process caused "no such file or directory"

请指导问题是什么，我是docker的新手。

与环境有关的信息

ubuntu@ip-172-31-32-125:~/go/src/hello$ ls
Dockerfile  webapp
ubuntu@ip-172-31-32-125:~/go/src/hello$ echo $GOPATH
/home/ubuntu/go

使用 go build webapp.go 命令编译了代码