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Torch Object Storage

Pre-signature Mechanism

Presigned POST Form (Go SDK)

This article presents example code for POST form presigning.

Sample Code

package main​
​
import (​
   "context"​
   "fmt"​
​
   "github.com/volcengine/ve-tos-golang-sdk/v2/tos"​
)​
​
func checkErr(err error) {​
   if err != nil {​
      if serverErr, ok := err.(*tos.TosServerError); ok {​
         fmt.Println("Error:", serverErr.Error())​
         fmt.Println("Request ID:", serverErr.RequestID)​
         fmt.Println("Response Status Code:", serverErr.StatusCode)​
         fmt.Println("Response Header:", serverErr.Header)​
         fmt.Println("Response Err Code:", serverErr.Code)​
         fmt.Println("Response Err Msg:", serverErr.Message)​
      } else {​
         fmt.Println("Error:", err)​
      }​
      panic(err)​
   }​
}​
​
func main() {​
   var (​
      accessKey = os.Getenv("TOS_ACCESS_KEY")​
      secretKey = os.Getenv("TOS_SECRET_KEY")​
​
      endpoint = "https://tos-cn-beijing.volces.com"​
      region   = "cn-beijing"​
     ​
      bucketName = "*** Provide your bucket name ***"​
​
      objectKey = "*** Provide your object key ***"​
      ctx       = context.Background()​
   )​
  ​
   client, err := tos.NewClientV2(endpoint, tos.WithRegion(region), tos.WithCredentials(tos.NewStaticCredentials(accessKey, secretKey)))​
   checkErr(err)​
   ​
  ​
   res, err := client.PreSignedPostSignature(ctx, &tos.PreSingedPostSignatureInput{​
      Bucket:  bucketName,​
      Key:     objectKey,​
      Expires: 3600,​
   })​
   fmt.Println("Policy:", res.Policy)​
   fmt.Println("OriginPolicy:", res.OriginPolicy)​
   fmt.Println("Algorithm:", res.Algorithm)​
   fmt.Println("Credential:", res.Credential)​
   fmt.Println("Date:", res.Date)​
   fmt.Println("Signature:", res.Signature)​
}​

Relevant Documentation

For detailed information on POST form presigning, see Including a signature in browser-based upload forms.

Last updated: 2025.09.19 17:30:18