Echo Server in Golang

Dockerfile

FROM golang:latest

RUN <<EOF
curl -L https://gist.githubusercontent.com/bthuilot/aae91fdb1745edde6713f0142f8cc0d3/raw/echo_server.go > /tmp/echo_server.go
go build -o /app/main /tmp/echo_server.go
EOF

EXPOSE 7890
ENTRYPOINT ["/app/main"]

echo_server.go

package main

import (
	"log"
	"net/http"
	"net/http/httputil"
)

func main() {
	http.HandleFunc("/health", func(writer http.ResponseWriter, request *http.Request) {
		_, _ = writer.Write([]byte("OK"))
		writer.WriteHeader(200)
	})
	http.HandleFunc("/", func(writer http.ResponseWriter, request *http.Request) {
		log.Println("received request")
		rawReq, err := httputil.DumpRequest(request, true)
		if err != nil {
			log.Println("error dumping request", err)
			writer.WriteHeader(500)
			_, _ = writer.Write([]byte("error dumping request"))
			return
		}
		log.Println(string(rawReq))
		_, _ = writer.Write(rawReq)
	})
	
	log.Println("starting echo server...")
	if err := http.ListenAndServe(":7890", nil); err != nil {
		log.Fatal(err)
	}
}

To build the docker image from the file without downloading run

curl -L https://gist.githubusercontent.com/bthuilot/aae91fdb1745edde6713f0142f8cc0d3/raw/Dockerfile | docker build -t bthuilot/echo-server:latest -