AlistGo/alist · error

[doubao_new] invalid block size from needed list: seq=%d siz

Error message

[doubao_new] invalid block size from needed list: seq=%d size=%d

What it means

Doubao_new validation of server data: an entry in NeededUploadBlocks carries Size <= 0, which is impossible to read or checksum. The client rejects it before attempting any I/O because buf := make([]byte, item.Size) would panic or misbehave.

Source

Thrown at drivers/doubao_new/driver.go:347

			groupSeqs = groupSeqs[:0]
			groupChecksums = groupChecksums[:0]
			groupSizes = groupSizes[:0]
			groupRealSize = 0
			groupExpectSum = 0
			groupBuf.Reset()
			if up != nil {
				percent := float64(uploadedBytes) / float64(totalSize) * 100
				up(percent)
			}
			return nil
		}

		for _, item := range needed.NeededUploadBlocks {
			if _, ok := blockMeta[item.Seq]; !ok {
				return nil, fmt.Errorf("[doubao_new] missing block meta for seq %d", item.Seq)
			}
			if item.Size <= 0 {
				return nil, fmt.Errorf("[doubao_new] invalid block size from needed list: seq=%d size=%d", item.Seq, item.Size)
			}
			offset := int64(item.Seq) * blockSize
			buf := make([]byte, int(item.Size))
			n, err := tmpFile.ReadAt(buf, offset)
			if err != nil && err != io.EOF && err != io.ErrUnexpectedEOF {
				return nil, err
			}
			if n != len(buf) {
				return nil, fmt.Errorf("[doubao_new] short read: seq=%d want=%d got=%d", item.Seq, len(buf), n)
			}
			buf = buf[:n]
			realAdler := adler32String(buf)
			if realAdler != item.Checksum {
				return nil, fmt.Errorf("[doubao_new] block checksum mismatch: seq=%d offset=%d adler32=%s step2=%s", item.Seq, offset, realAdler, item.Checksum)
			}
			payloadStart := groupBuf.Len()
			groupBuf.Write(buf)
			payloadEnd := groupBuf.Len()

View on GitHub (pinned to 843d9dc814)

Solutions

1. If ALL uploads fail this way, suspect an API field rename — update/rebuild the doubao_new driver
2. Retry once to rule out a one-off malformed response
3. Capture the raw needed-blocks JSON (add temporary logging) and compare field names against the driver's structs
4. Report upstream with the raw response body
5. Re-login to get a fresh session; some malformed responses correlate with expired auth

for _, item := range needed.NeededUploadBlocks {
    if item.Size <= 0 {
        return fmt.Errorf("server returned invalid block size for seq %d; aborting before I/O", item.Seq)
    }
}

func validBlockItem(item NeededBlock) bool {
    return item.Seq >= 0 && item.Size > 0 && item.Checksum != ""
}

// treat as API contract break: fail fast with the raw entry for diagnostics
if !validBlockItem(item) {
    log.Printf("[doubao_new] malformed needed entry: %+v", item)
    return nil, fmt.Errorf("[doubao_new] invalid block size from needed list: seq=%d size=%d", item.Seq, item.Size)
}

When it happens

Trigger: The needed-blocks endpoint returns a zero/negative size for a seq — server-side data anomaly, response shape change where Size unmarshals from the wrong field (so stays 0), or the seq refers to a block the server already has and the entry is malformed.

Common situations: Doubao web API contract change renaming size fields (Size vs BlockSize vs size), partial JSON so numbers stay zero, or server bug. Almost always paired with a broader upload failure for all files, not one specific file.

Related errors

• file size cannot be zero
• [doubao_new] merge blocks invalid body len: got=%d expect=%d
• [doubao_new] merge blocks incomplete: %v
• [doubao_new] merge blocks missing seq %d
• [doubao_new] missing block meta for seq %d

AI-assisted analysis of AlistGo/alist@843d9dc814 (2026-08-15). Data as JSON: /api/errors/72f4aa062482cce6. Report an issue: GitHub.