create mini http client

test_server/main.go

@@ -0,0 +1,14 @@
+package main
+
+import (
+	"fmt"
+	"net/http"
+)
+
+func main() {
+	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprintf(w, "Hello World!")
+		w.WriteHeader(200)
+	})
+	http.ListenAndServe(":8081", nil)
+}