Gin编写图床后端-上传图片代码实现
日常我们会使用到到图床来存放图片,但是大致流程是什么样子的来??
图床原理
实现一个HTTP服务器,用这个服务器存储图片,针对每个图片提供一个唯一的url,借助这个url就可以将图片展示到其他网页上
后端代码实现
项目接口
首先,我们需要建立Gin框架 post请求访问,上传图片,判断图片是否符合,在上传图片,返回Url地址,浏览器就可以正常访问
app.ini
[app]
HttpPort = 8000
RuntimeRootPath = runtime/
ImagePrefixUrl = http://127.0.0.1:8000
ImageSavePath = upload/images/
# MB
ImageMaxSize = 5
ImageAllowExts = .jpg,.jpeg,.png,.gif
LogSavePath = logs/
LogSaveName = log
LogFileExt = log
TimeFormat = 20060102
app/upload.go
package app
import (
"ImagesUpload/pkg/e"
"ImagesUpload/pkg/logging"
"ImagesUpload/pkg/upload"
"fmt"
"github.com/gin-gonic/gin"
"net/http"
"strconv"
"time"
)
//获取ip
func GetRequestIP(c *gin.Context) string {
reqIP := c.ClientIP()
if reqIP == "::1" {
reqIP = "127.0.0.1"
}
return reqIP
}
func UploadImage(c *gin.Context) {
code := e.SUCCESS
data := make(map[string]string)
t := time.Now()
year := t.Year() // type int
month := t.Month() // type time.Month
file, image, err := c.Request.FormFile("image")
if err != nil {
logging.Warn(err)
code = e.ERROR
c.JSON(http.StatusOK, gin.H{
"code": code,
"msg": e.GetMsg(code),
"data": data,
})
}
if image == nil {
code = e.INVALID_PARAMS
} else {
imageName := upload.GetImageName(image.Filename)
fullPath := upload.GetImageFullPath() + strconv.Itoa(year) + strconv.Itoa(int(month))
savePath := upload.GetImagePath() + strconv.Itoa(year) + strconv.Itoa(int(month))
src := fullPath + "/" + imageName
fmt.Println(imageName, fullPath, savePath, src)
if !upload.CheckImageExt(imageName) || !upload.CheckImageSize(file) {
code = e.ERROR_UPLOAD_CHECK_IMAGE_FORMAT
fmt.Println(e.GetMsg(code))
} else {
err := upload.CheckImage(fullPath)
if err != nil {
logging.Warn(err)
code = e.ERROR_UPLOAD_CHECK_IMAGE_FAIL
} else if err := c.SaveUploadedFile(image, src); err != nil {
logging.Warn(err)
code = e.ERROR_UPLOAD_SAVE_IMAGE_FAIL
} else {
logging.Info("访问者IP:",GetRequestIP(c),"上传地址连接:",upload.GetImageFullUrl(imageName))
data["image_url"] = upload.GetImageFullUrl(imageName)
data["image_save_url"] = savePath + "/" + imageName
}
}
}
c.JSON(http.StatusOK, gin.H{
"code": code,
"msg": e.GetMsg(code),
"data": data,
})
}
pkg
pkg/e/code.go
package e
const (
SUCCESS = 200
ERROR = 500
INVALID_PARAMS = 400
// 保存图片失败
ERROR_UPLOAD_SAVE_IMAGE_FAIL = 30001
// 检查图片失败
ERROR_UPLOAD_CHECK_IMAGE_FAIL = 30002
// 校验图片错误,图片格式或大小有问题
ERROR_UPLOAD_CHECK_IMAGE_FORMAT = 30003
)
pkg/e/msg.go
package e
var MsgFlags = map[int]string {
SUCCESS: "ok",
ERROR: "fail",
INVALID_PARAMS: "请求参数错误",
// 保存图片失败
ERROR_UPLOAD_SAVE_IMAGE_FAIL: "保存图片失败",
// 检查图片失败
ERROR_UPLOAD_CHECK_IMAGE_FAIL: "检查图片失败",
// 校验图片错误,图片格式或大小有问题
ERROR_UPLOAD_CHECK_IMAGE_FORMAT: "校验图片错误,图片格式或大小有问题",
}
func GetMsg(code int) string {
msg ,ok := MsgFlags[code]
if ok{
return msg
}
return MsgFlags[ERROR]
}
pkg/file/file.go
package file
import (
"io/ioutil"
"mime/multipart"
"os"
"path"
)
/*
GetSize:获取文件大小
GetExt:获取文件后缀
CheckNotExist:检查文件是否存在
CheckPermission:检查文件权限
IsNotExistMkDir:如果不存在则新建文件夹
MkDir:新建文件夹
Open:打开文件
*/
//GetSize:获取文件大小
func GetSize(f multipart.File) (int, error) {
content, err := ioutil.ReadAll(f)
return len(content), err
}
//GetExt:获取文件后缀
func GetExt(fileName string) string {
return path.Ext(fileName)
}
//CheckNotExist:检查文件是否存在
func CheckNotExist(src string) bool {
_, err := os.Stat(src)
return os.IsNotExist(err)
}
//CheckPermission:检查文件权限
func CheckPermission(src string) bool {
_, err := os.Stat(src)
return os.IsPermission(err)
}
//IsNotExistMkDir:如果不存在则新建文件夹
func IsNotExistMkDir(src string) error {
if notExist := CheckNotExist(src); notExist == true {
if err := MkDir(src); err != nil {
return err
}
}
return nil
}
//MkDir:新建文件夹
func MkDir(src string) error {
err := os.MkdirAll(src, os.ModePerm)
if err != nil {
return err
}
return nil
}
//Open:打开文件
func Open(name string, flag int, perm os.FileMode) (*os.File, error) {
f, err := os.OpenFile(name, flag, perm)
if err != nil {
return nil, err
}
return f, nil
}
pkg/logging/file.go
package logging
import (
"ImagesUpload/pkg/file"
"ImagesUpload/setting"
"fmt"
"os"
"time"
)
func getLogFilePath() string {
return fmt.Sprintf("%s%s", setting.AppSetting.RuntimeRootPath, setting.AppSetting.LogSavePath)
}
func getLogFileName() string {
return fmt.Sprintf("%s%s.%s",
setting.AppSetting.LogSaveName,
time.Now().Format(setting.AppSetting.TimeFormat),
setting.AppSetting.LogFileExt,
)
}
func openLogFile(fileName, filePath string) (*os.File, error) {
dir, err := os.Getwd()
if err != nil {
return nil, fmt.Errorf("os.Getwd err: %v", err)
}
src := dir + "/" + filePath
perm := file.CheckPermission(src)
if perm == true {
return nil, fmt.Errorf("file.CheckPermission Permission denied src: %s", src)
}
err = file.IsNotExistMkDir(src)
if err != nil {
return nil, fmt.Errorf("file.IsNotExistMkDir src: %s, err: %v", src, err)
}
f, err := file.Open(src+fileName, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
if err != nil {
return nil, fmt.Errorf("Fail to OpenFile :%v", err)
}
return f, nil
}
pkg/logging/log.go
package logging
import (
"fmt"
"log"
"os"
"path/filepath"
"runtime"
)
type Level int
var (
F *os.File
DefaultPrefix = ""
DefaultCallerDepth = 2
logger *log.Logger
logPrefix = ""
levelFlags = []string{"DEBUG", "INFO", "WARN", "ERROR", "FATAL"}
)
const (
DEBUG Level = iota
INFO
WARNING
ERROR
FATAL
)
func Setup() {
var err error
filePath := getLogFilePath()
fileName := getLogFileName()
F, err = openLogFile(fileName, filePath)
if err != nil {
log.Fatalln(err)
}
logger = log.New(F, DefaultPrefix, log.LstdFlags)
}
func Debug(v ...interface{}) {
setPrefix(DEBUG)
logger.Println(v)
}
func Info(v ...interface{}) {
setPrefix(INFO)
logger.Println(v)
}
func Warn(v ...interface{}) {
setPrefix(WARNING)
logger.Println(v)
}
func Error(v ...interface{}) {
setPrefix(ERROR)
logger.Println(v)
}
func Fatal(v ...interface{}) {
setPrefix(FATAL)
logger.Fatalln(v)
}
func setPrefix(level Level) {
_, file, line, ok := runtime.Caller(DefaultCallerDepth)
if ok {
logPrefix = fmt.Sprintf("[%s][%s:%d]", levelFlags[level], filepath.Base(file), line)
} else {
logPrefix = fmt.Sprintf("[%s]", levelFlags[level])
}
logger.SetPrefix(logPrefix)
}
pkg/logging/logrus.go
package logging
import (
"fmt"
"github.com/sirupsen/logrus"
)
func Logger() *logrus.Logger {
//now := time.Now()
//logFilePath := getLogFilePath()
//logFileName := getLogFileFullPath()
//日志文件
//fileName := path.Join(logFilePath, logFileName)
//if _, err := os.Stat(fileName); err != nil {
// if _, err := os.Create(fileName); err != nil {
// fmt.Println(err.Error())
// }
//}
//写入文件
filePath := getLogFilePath()
fileName := getLogFileName()
F, err := openLogFile(fileName, filePath)
if err != nil {
fmt.Println("日志写入失败,请检查")
}
//实例化
logger := logrus.New()
//设置输出
logger.Out = F
//设置日志级别
logger.SetLevel(logrus.DebugLevel)
//设置日志格式
logger.SetFormatter(&logrus.TextFormatter{
TimestampFormat: "2006-01-02 15:04:05",
})
return logger
}
pkg/upload/image.go
package upload
import (
"ImagesUpload/pkg/file"
"ImagesUpload/pkg/logging"
"ImagesUpload/pkg/util"
"ImagesUpload/setting"
"fmt"
"log"
"mime/multipart"
"os"
"path"
"strconv"
"strings"
"time"
)
/*
GetImageFullUrl:获取图片完整访问 URL
GetImageName:获取图片名称
GetImagePath:获取图片路径
GetImageFullPath:获取图片完整路径
CheckImageExt:检查图片后缀
CheckImageSize:检查图片大小
CheckImage:检查图片
*/
//GetImageFullUrl:获取图片完整访问 URL
func GetImageFullUrl(name string) string {
t := time.Now()
year := t.Year() // type int
month := t.Month() // type time.Month
return setting.AppSetting.ImagePrefixUrl + "/" + GetImagePath() + strconv.Itoa(year) + strconv.Itoa(int(month)) + "/" + name
}
//GetImageName:获取图片名称
func GetImageName(name string) string {
ext := path.Ext(name)
fileName := strings.TrimSuffix(name, ext)
fileName = util.EncodeMD5(fileName)
return fileName + ext
}
//GetImagePath:获取图片路径
func GetImagePath() string {
return setting.AppSetting.ImageSavePath
}
//GetImageFullPath:获取图片完整路径
func GetImageFullPath() string {
return setting.AppSetting.RuntimeRootPath + GetImagePath()
}
//CheckImageExt:检查图片后缀
func CheckImageExt(fileName string) bool {
ext := file.GetExt(fileName)
for _, allowExt := range setting.AppSetting.ImageAllowExts {
if strings.ToUpper(allowExt) == strings.ToUpper(ext) {
return true
}
}
return false
}
//CheckImageSize:检查图片大小
func CheckImageSize(f multipart.File) bool {
size, err := file.GetSize(f)
if err != nil {
log.Println(err)
logging.Warn(err)
return false
}
return size <= setting.AppSetting.ImageMaxSize
}
//CheckImage:检查图片
func CheckImage(src string) error {
dir, err := os.Getwd()
if err != nil {
return fmt.Errorf("os.Getwd err: %v", err)
}
err = file.IsNotExistMkDir(dir + "/" + src)
if err != nil {
return fmt.Errorf("file.IsNotExistMkDir err: %v", err)
}
perm := file.CheckPermission(src)
if perm == true {
return fmt.Errorf("file.CheckPermission Permission denied src: %s", src)
}
return nil
}
pkg/util/md5.go
package util
import (
"crypto/md5"
"encoding/hex"
)
func EncodeMD5(value string) string {
m := md5.New()
m.Write([]byte(value))
return hex.EncodeToString(m.Sum(nil))
}
routers/router.go
package routers
import (
"ImagesUpload/app"
"ImagesUpload/pkg/upload"
"github.com/gin-gonic/gin"
"net/http"
)
func InitRouter() *gin.Engine {
r := gin.New()
r.Use(gin.Logger())
r.Use(gin.Recovery())
r.StaticFS("/upload/images", http.Dir(upload.GetImageFullPath()))
r.POST("upload", app.UploadImage)
return r
}
setting/setting.go
package setting
import (
"github.com/go-ini/ini"
"log"
)
type App struct {
HttpPort int
RuntimeRootPath string
ImagePrefixUrl string
ImageSavePath string
ImageMaxSize int
ImageAllowExts []string
LogSavePath string
LogSaveName string
LogFileExt string
TimeFormat string
}
var AppSetting = &App{}
func Setup() {
Cfg, err := ini.Load("conf/app.ini")
if err != nil {
log.Fatalf("Fail to parse 'conf/app.ini': %v", err)
}
err = Cfg.Section("app").MapTo(AppSetting)
if err != nil {
log.Fatalf("Cfg.MapTo AppSetting err: %v", err)
}
AppSetting.ImageMaxSize = AppSetting.ImageMaxSize * 1024 * 1024
}
main.go
package main
import (
"ImagesUpload/pkg/logging"
"ImagesUpload/routers"
"ImagesUpload/setting"
"fmt"
"log"
"net/http"
)
func main() {
setting.Setup()
logging.Setup()
router := routers.InitRouter()
fmt.Println("启动端口:", setting.AppSetting.HttpPort)
s := &http.Server{
Addr: fmt.Sprintf(":%d", setting.AppSetting.HttpPort),
Handler: router,
}
if err := s.ListenAndServe(); err != nil {
log.Printf("Listen: %s\n", err)
}
}
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