AlistGo/alist · error

up.Msg

Error message

up.Msg

What it means

CloudreveV4 local upload chunk got HTTP 200 but the JSON envelope carries a non-zero code; the server's message up.Msg is returned. This is the application-level rejection of an otherwise HTTP-successful chunk PUT on V4.

Source

Thrown at drivers/cloudreve_v4/util.go:305

			res, err := base.HttpClient.Do(req)
			if err != nil {
				return err
			}
			defer res.Body.Close()
			if res.StatusCode != 200 {
				return errors.New(res.Status)
			}
			body, err := io.ReadAll(res.Body)
			if err != nil {
				return err
			}
			var up Resp
			err = json.Unmarshal(body, &up)
			if err != nil {
				return err
			}
			if up.Code != 0 {
				return errors.New(up.Msg)
			}
			return nil
		}()
		if err == nil {
			retryCount = 0
			finish += byteSize
			up(float64(finish) * 100 / float64(file.GetSize()))
			chunk++
		} else {
			retryCount++
			if retryCount > maxRetries {
				return fmt.Errorf("upload failed after %d retries due to server errors, error: %s", maxRetries, err)
			}
			backoff := time.Duration(1<<retryCount) * time.Second
			utils.Log.Warnf("[Cloudreve-Remote] server errors while uploading, retrying after %v...", backoff)
			time.Sleep(backoff)
		}
	}

View on GitHub (pinned to 843d9dc814)

Solutions

1. Start a new upload instead of resuming — server-side session state is the usual culprit.
2. Raise the V4 storage policy size/chunk limits if failures cluster at a size boundary.
3. Avoid concurrent uploads of the identical file through this driver.
4. Correlate with V4 server logs for the precise code/message.

if err := d.upLocal(...); err != nil {
    if strings.Contains(err.Error(), "session") { // up.Msg mentioning session state
        return d.upLocal(...) // one clean restart with a new session
    }
    return err
}

When it happens

Trigger: Chunk body unmarshals fine, up.Code != 0. Occurs when the upload session is completed/invalid, chunk index already committed, credential scope mismatch, or policy limits (size/count) exceeded.

Common situations: Retrying after a partial failure where earlier chunks already landed; resuming a finished session; per-policy file size cap hit mid-upload; duplicate uploads racing on the same session.

Related errors

• up.Msg
• server returns no url
• r.Msg
• res.Status
• string(data)

AI-assisted analysis of AlistGo/alist@843d9dc814 (2026-08-15). Data as JSON: /api/errors/e7dc1fab8403b526. Report an issue: GitHub.