Function parseIndexSection

go/bundle/decoder.go:145–203

https://wpack-wg.github.io/bundled-responses/draft-ietf-wpack-bundled-responses.html#name-the-index-section

(sectionContents []byte, sectionsStart uint64, sos []sectionOffset)

// https://wpack-wg.github.io/bundled-responses/draft-ietf-wpack-bundled-responses.html#name-the-index-section
func parseIndexSection(sectionContents []byte, sectionsStart uint64, sos []sectionOffset) ([]requestEntryWithOffset, error) {
	dec := cbor.NewDecoder(bytes.NewBuffer(sectionContents))
	numUrls, err := dec.DecodeMapHeader()
	if err != nil {
		return nil, fmt.Errorf("bundle.index: failed to decode index section map header: %v", err)
	}
	requests := []requestEntryWithOffset{}

	respso, respSectionRelOffset, found := FindSection(sos, "responses")
	if !found {
		return nil, fmt.Errorf("bundle.index: \"responses\" section not found")
	}
	respSectionOffset := sectionsStart + respSectionRelOffset
	makeRelativeToStream := func(offset, length uint64) (uint64, uint64, error) {
		if offset+length > respso.Length {
			return 0, 0, errors.New("bundle.index: response length out-of-range")
		}
		return respSectionOffset + offset, length, nil
	}

	for i := uint64(0); i < numUrls; i++ {
		rawUrl, err := dec.DecodeTextString()
		if err != nil {
			return nil, fmt.Errorf("bundle.index[%d]: Failed to decode map key: %v", i, err)
		}
		parsedUrl, err := url.Parse(rawUrl)
		if err != nil {
			return nil, fmt.Errorf("bundle.index[%d]: Failed to parse URL: %v", i, err)
		}
		if parsedUrl.Fragment != "" {
			return nil, fmt.Errorf("bundle.index[%d]: URL contains fragment: %q", i, rawUrl)
		}
		if parsedUrl.User != nil {
			return nil, fmt.Errorf("bundle.index[%d]: URL contains credentials: %q", i, rawUrl)
		}

		numItems, err := dec.DecodeArrayHeader()
		if err != nil {
			return nil, fmt.Errorf("bundle.index[%d]: Failed to decode value array header: %v", i, err)
		}
		if numItems != 2 {
			return nil, fmt.Errorf("bundle.index[%d]: value array must be exactly 2 elements: offset and length.", i)
		}
		offset, err := dec.DecodeUint()
		if err != nil {
			return nil, fmt.Errorf("bundle.index[%d]: Failed to decode offset: %v", i, err)
		}
		length, err := dec.DecodeUint()
		if err != nil {
			return nil, fmt.Errorf("bundle.index[%d]: Failed to decode length: %v", i, err)
		}
		offset, length, err = makeRelativeToStream(offset, length)
		if err != nil {
			return nil, fmt.Errorf("bundle.index[%d]: %v", i, err)
		}
		requests = append(requests, requestEntryWithOffset{Request: Request{URL: parsedUrl}, Offset: offset, Length: length})
	}
	return requests, nil