Golang Web开发之Gin文件上传

// FormFile returns the first file for the provided form key.
func (c *Context) FormFile(name string) (*multipart.FileHeader, error) {
  if c.Request.MultipartForm == nil {
    if err := c.Request.ParseMultipartForm(c.engine.MaxMultipartMemory); err != nil {
      return nil, err
    }
  }
  f, fh, err := c.Request.FormFile(name)
  if err != nil {
    return nil, err
  }
  f.Close()
  return fh, err
}

// SaveUploadedFile uploads the form file to specific dst.
func (c *Context) SaveUploadedFile(file *multipart.FileHeader, dst string) error {
  src, err := file.Open()
  if err != nil {
    return err
  }
  defer src.Close()


  out, err := os.Create(dst)
  if err != nil {
    return err
  }
  defer out.Close()


  _, err = io.Copy(out, src)
  return err
}

package main


import (
  "fmt"
  "log"
  "net/http"


  "github.com/gin-gonic/gin"
)


func main() {
  r := gin.Default()
  // 设置文件上传大小限制，默认是32m
  r.MaxMultipartMemory = 64 << 20  // 64MiB


  r.POST("/upload", func(c *gin.Context) {
    file, _ := c.FormFile("file")
    
    // 打印上传的文件名
    log.Println(file.Filename)
    // 将上传的文件，保存到./upload/1111.jpg 文件中
    path := "./upload/" + file.Filename
    c.SaveUploadedFile(file, path)
    c.String(http.StatusOK, fmt.Sprintf("'%s' uploaded!!!", file.Filename))
  })


  r.Run()
}

现在，让我们使用postman模拟上传一个文件：

可以看到成功上传了：

[GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.


[GIN-debug] [WARNING] Running in "debug" mode. Switch to "release" mode in production.
 - using env:   export GIN_MODE=release
 - using code:  gin.SetMode(gin.ReleaseMode)
[GIN-debug] POST   /upload                   --> main.main.func1 (3 handlers)
[GIN-debug] Environment variable PORT is undefined. Using port :8080 by default
[GIN-debug] Listening and serving HTTP on :8080
2021/10/13 18:36:31 80b3d377da26e626.jpg
[GIN] 2021/10/13 - 18:36:31 | 200 |     33.8653ms |       127.0.0.1 | POST     "/upload"