Go语言通用方法笔记

package common

import (
	"bufio"
	"bytes"
	"crypto/sha256"
	"encoding/hex"
	"fmt"
	"io"
	"log"
	"os"
	"regexp"
	"runtime"
	"strconv"
	"strings"
	"time"

	"github.com/xx/config"
	"github.com/xx/config/e"
)

var (
	BASE_IP       = config.Config.Services.Web.Baseip
	PEOPLEIMGPATH = config.Config.Services.Image.Peopleimgpath
	IMGBASEPATH   = config.Config.Services.Image.Imgbasepath
	ACCESSPATH    = config.Config.Services.Image.Accessbasepath

	//报警参数配置//map
	ALARMEVENT_CONFIG = "alarm_event_configure"

	//记录上次报警时间前缀 map
	LASTALARM_PRE           = "alarm_lastesttime_"
	BLACKLIST_LASTALARM_PRE = LASTALARM_PRE + "blacklist_"
	PROTECT_LASTALARM_PRE   = LASTALARM_PRE + "protectarea_"
	HOTSPOT_LASTALARM_PRE   = LASTALARM_PRE + "hotspot_"

	//摄像机列表 set
	UUID_PRE       = "alarm_camerauuid_"
	PROTECT_UUID   = UUID_PRE + "protectarea"
	BLACKLIST_UUID = UUID_PRE + "blacklist"
	HOTSPOT_UUID   = UUID_PRE + "hotspot"
	DOUBT_UUID     = UUID_PRE + "doubt"

	//可疑人员临时数据 map
	DOUBT_PRE        = "alarm_doubt_"
	DOUBT_SHORTTRACK = DOUBT_PRE + "shorttrack"
	DOUBT_LONGREPEAT = DOUBT_PRE + "longrepeat"
	DOUBT_LONGSTAY   = DOUBT_PRE + "longstay"

	ALARM_CHANNEL = "AlarmWebsocket" //报警websocket使用
)

/*获取某年的某月一共多少天*/
func GetDaysByYearMonth(year int, month int) (days int) {
	if month != 2 {
		if month == 4 || month == 6 || month == 9 || month == 11 {
			days = 30

		} else {
			days = 31
		}
	} else {
		if ((year%4) == 0 && (year%100) != 0) || (year%400) == 0 {
			days = 29
		} else {
			days = 28
		}
	}
	return
}

func TimeCost(str string, start time.Time) {
	terminal := time.Since(start)
	fmt.Println(str, terminal)
}
func CreateFile(path string, content []byte) (errCode int64) {
	//创建文件
	file, err := os.Create(path)
	if err != nil {
		log.Println("CreateFile1 file err:", err)
		return e.ERROR_ALARM_CREATE_FILE

	}
	defer file.Close()
	w := bufio.NewWriter(file)
	_, err = w.Write(content)
	if err != nil {
		log.Println("CreateFile2 file err:", err)
		return e.ERROR_ALARM_CREATE_FILE
	}
	return 0
}

func SplitImageBase64Content(str string) (suff, content string) {
	splitstr := strings.Split(str, ",")
	if len(splitstr) != 2 {
		return "", ""
	}
	suff = splitstr[0][11 : len(splitstr[0])-7]
	content = splitstr[1]
	return
}
func GetImageSuffixes(str string) string {
	reg := regexp.MustCompile(`^data:image/.*;base64`)
	allstr := reg.FindAllString(str, -1)
	if len(allstr) == 0 {
		return ""
	}
	strPre := allstr[0]
	return strPre[11 : len(strPre)-7]
}

func HashSHA256File(filePath string) string {
	var hashValue string
	file, err := os.Open(filePath)
	if err != nil {
		log.Println("HashSHA256File file err:", err)
		return hashValue
	}
	defer file.Close()
	hash := sha256.New()
	if _, err := io.Copy(hash, file); err != nil {
		return hashValue
	}
	hashInBytes := hash.Sum(nil)
	hashValue = hex.EncodeToString(hashInBytes)
	return hashValue

}
func HashSHA256Byte(str []byte) (sha256str string) {

	h := sha256.New()
	h.Write(str)
	sha256str = hex.EncodeToString(h.Sum(nil))
	return
}

func SplitNameAndSuf(imagename string) (name, suf string) {
	nameArr := strings.Split(imagename, ".")
	suf = nameArr[len(nameArr)-1]
	l := len(imagename) - (len(suf) + 1)
	name = string([]rune(imagename)[:l])
	return
}

//yadd需要加几年 madd 需要加几个月
func SpliceYearMonth(t, yadd, madd int) string {
	y := strconv.Itoa(time.Unix(int64(t), 0).Year() + yadd)
	n := strconv.Itoa(int(time.Unix(int64(t), 0).Month()) + madd)
	if len(n) == 1 {
		n = "0" + n
	}
	return y + n

}
func SpliceYearMonthToStr(y, n int) string {
	ystr := strconv.Itoa(y)
	nstr := strconv.Itoa(n)
	if len(nstr) == 1 {
		nstr = "0" + nstr
	}
	return ystr + nstr

}

//判断目录是否存在，不存在则创建，创建失败则返回错误信息
func PathExists(path string) (exist bool) {
	_, err := os.Stat(path)
	if err == nil {
		log.Println("PathExists file err:", err)
		return false
	}
	if os.IsNotExist(err) {
		err = os.MkdirAll(path, 0777)
	}
	return true
}

func FileExists(path string) (bool, error) {
	_, err := os.Stat(path)
	if err == nil {
		return true, nil
	}
	if os.IsNotExist(err) {
		return false, nil
	}
	return false, err
}

//获取操作系统的目录分隔符
func GetSeparator() (s string) {
	var ostype = runtime.GOOS
	if ostype == "windows" {
		s = "\\"
	} else if ostype == "linux" {
		s = "/"
	}
	return
}

//字符串拼接
func StrSub(strs ...string) string {
	var buffers bytes.Buffer
	for _, str := range strs {
		buffers.WriteString(str)
	}
	return buffers.String()
}