added server using gorilla mux

.env

@@ -0,0 +1 @@
+PORT=3001

go.mod

@@ -0,0 +1,8 @@
+module github.com/KulwinderSingh07/POW-Blockchain
+
+go 1.20
+
+require (
+	github.com/gorilla/mux v1.8.0
+	github.com/joho/godotenv v1.5.1
+)

go.sum

@@ -0,0 +1,4 @@
+github.com/gorilla/mux v1.8.0 h1:i40aqfkR1h2SlN9hojwV5ZA91wcXFOvkdNIeFDP5koI=
+github.com/gorilla/mux v1.8.0/go.mod h1:DVbg23sWSpFRCP0SfiEN6jmj59UnW/n46BH5rLB71So=
+github.com/joho/godotenv v1.5.1 h1:7eLL/+HRGLY0ldzfGMeQkb7vMd0as4CfYvUVzLqw0N0=
+github.com/joho/godotenv v1.5.1/go.mod h1:f4LDr5Voq0i2e/R5DDNOoa2zzDfwtkZa6DnEwAbqwq4=

main.go

@@ -0,0 +1,54 @@
+package main
+
+import (
+	"encoding/json"
+	"io"
+	"log"
+	"net/http"
+	"os"
+	"time"
+
+	"github.com/gorilla/mux"
+	"github.com/joho/godotenv"
+)
+
+func main() {
+	err := godotenv.Load()
+	if err != nil {
+		log.Fatal(err)
+	}
+	log.Fatal(run())
+}
+
+func run() error {
+	mux := makeMuxRouter()
+	httpPort := os.Getenv("PORT")
+	log.Println("Http server Listening on port :", httpPort)
+	s := &http.Server{
+		Addr:           ":" + httpPort,
+		Handler:        mux,
+		ReadTimeout:    10 * time.Second,
+		WriteTimeout:   10 * time.Second,
+		MaxHeaderBytes: 1 << 20,
+	}
+	if err := s.ListenAndServe(); err != nil {
+		return err
+	}
+	return nil
+}
+
+func testing(res http.ResponseWriter, req *http.Request) {
+	data, err := json.Marshal("hello")
+	if err != nil {
+		http.Error(res, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	io.WriteString(res, string(data))
+}
+
+func makeMuxRouter() http.Handler {
+	muxRouter := mux.NewRouter()
+	muxRouter.HandleFunc("/", testing).Methods("GET")
+	muxRouter.HandleFunc("/", testing).Methods("POST")
+	return muxRouter
+}