func()

in oss/downloader.go [529:581]

• 43 lines of code
• 5 McCabe index (conditional complexity)

func (d *downloaderDelegate) downloadChunk(chunk downloaderChunk, hash hash.Hash64) (downloadedChunk, error) {
	// Get the next byte range of data
	var request GetObjectRequest
	copyRequest(&request, d.request)

	getFn := func(ctx context.Context, httpRange HTTPRange) (output *ReaderRangeGetOutput, err error) {
		// update range
		request.Range = nil
		rangeStr := httpRange.FormatHTTPRange()
		request.RangeBehavior = nil
		if rangeStr != nil {
			request.Range = rangeStr
			request.RangeBehavior = Ptr("standard")
		}

		result, err := d.client.GetObject(ctx, &request, d.options.ClientOptions...)
		if err != nil {
			return nil, err
		}

		return &ReaderRangeGetOutput{
			Body:          result.Body,
			ETag:          result.ETag,
			ContentLength: result.ContentLength,
			ContentRange:  result.ContentRange,
		}, nil
	}

	reader, _ := NewRangeReader(d.context, getFn, &HTTPRange{chunk.start, chunk.size}, d.etag)
	defer reader.Close()

	var (
		r     io.Reader = reader
		crc64 uint64    = 0
	)
	if hash != nil {
		hash.Reset()
		r = io.TeeReader(reader, hash)
	}

	n, err := io.Copy(&chunk, r)
	d.incrWritten(n)

	if hash != nil {
		crc64 = hash.Sum64()
	}

	return downloadedChunk{
		start: chunk.start,
		size:  n,
		crc64: crc64,
	}, err
}