utils.go

package main

import (
	"bytes"
	"crypto/md5"
	"encoding/hex"
	"encoding/json"
	"io"
	"log"
	"os"
	"sync"
)

var lock sync.Mutex

// Marshal – Convert object to JSON
var Marshal = func(v interface{}) (io.Reader, error) {
	b, err := json.MarshalIndent(v, "", "\t")
	if err != nil {
		return nil, err
	}
	return bytes.NewReader(b), nil
}

// Unmarshal – Convert JSON to object
var Unmarshal = func(r io.Reader, v CheckRule) error {
	return json.NewDecoder(r).Decode(v)
}

// GetMD5Hash – return md5 of string
func GetMD5Hash(text string) string {
	hasher := md5.New()
	hasher.Write([]byte(text))
	return hex.EncodeToString(hasher.Sum(nil))
}

// SetupLogs – Open file for logs and set it as logging endpoint
func SetupLogs() {
	f, err := os.OpenFile("logs/logs.txt", os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
	if err != nil {
		log.Fatalf("Error opening file: %v", err)
	}
	log.SetOutput(f)
}

// Save content to JSON file
func Save(path string, v interface{}) error {
	lock.Lock()
	defer lock.Unlock()
	f, err := os.Create(path)
	if err != nil {
		return err
	}
	defer f.Close()
	r, err := Marshal(v)
	if err != nil {
		return err
	}
	_, err = io.Copy(f, r)
	return err
}

// Load file
func Load(path string, v CheckRule) error {
	lock.Lock()
	defer lock.Unlock()
	f, err := os.Open(path)
	if err != nil {
		return err
	}
	defer f.Close()

	return Unmarshal(f, v)
}