main.go

/**
 * Copyright 2021 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// [START gke_hello_app]
// [START container_hello_app]
package main

import (
	"fmt"
	"log"
	"net/http"
	"os"
	"bytes"
	"encoding/json"
	"io/ioutil"
)

func main() {
	// register hello function to handle all requests
	mux := http.NewServeMux()
	mux.HandleFunc("/", hello)

	// use PORT environment variable, or default to 8080
	port := os.Getenv("PORT")
	if port == "" {
		port = "8080"
	}

	// start the web server on port and accept requests
	log.Printf("Server listening on port %s", port)
	log.Fatal(http.ListenAndServe(":"+port, mux))
}

// hello responds to the request with a plain-text "Hello, world" message.
func hello(w http.ResponseWriter, r *http.Request) {

	var bodyBytes []byte
	var err error

	log.Printf("version 1.3")
	log.Printf("Serving request: %s", r.URL.Path)
	host, _ := os.Hostname()
	fmt.Fprintf(w, "Hello, world!\n")
	fmt.Fprintf(w, "Version: 1.0.0\n")
	fmt.Fprintf(w, "Hostname: %s\n", host)
  for name, values := range r.Header {
    // Loop over all values for the name.
    for _, value := range values {
        fmt.Fprintf(w, "Request Header: %s = %s\n", name, value)
    }
  }

  if r.Body != nil {
		bodyBytes, err = ioutil.ReadAll(r.Body)
		if err != nil {
			fmt.Printf("Body reading error: %v", err)
			return
		}
		defer r.Body.Close()
	}

	fmt.Printf("Headers: %+v\n", r.Header)
	str1 := string(bodyBytes[:])
  fmt.Println("byte array string =",str1)

	if len(bodyBytes) > 0 {
		fmt.Println("length of bytearray",len(bodyBytes))
		var prettyJSON bytes.Buffer
		if err = json.Indent(&prettyJSON, bodyBytes, "", "\t"); err != nil {
			fmt.Printf("JSON parse error: %v", err)
			return
		}
		fmt.Println(string(prettyJSON.Bytes()))
	} else {
		fmt.Printf("Body: No Body Supplied\n")
	}

	// CORS headers
	//w.Header().Set("Access-Control-Allow-Origin", "http://localhost:8000")
	//w.Header().Set("Access-Control-Allow-Methods", "GET,PUT,POST,DELETE,OPTIONS")
	//w.Header().Set("Access-Control-Allow-Credentials", "true")
	//w.Header().Set("Access-Control-Allow-Headers", "Accept-Encoding,Authorization,X-Forwarded-For,Content-Type,Origin,Server")


}

// [END container_hello_app]
// [END gke_hello_app]