Method DecodeContent

library/cpp/http/push_parser/http_parser.cpp:278–337

}

bool THttpParser::DecodeContent(TString& decodedContent) const {
    if (!ContentEncoding_ || ContentEncoding_ == "identity" || ContentEncoding_ == "none") {
        decodedContent = Content_;
        return false;
    }

    TMemoryInput in(Content_.data(), Content_.size());
    if (ContentEncoding_ == "gzip") {
        auto decompressor = TZLibDecompress(&in, ZLib::GZip);
        if (!GzipAllowMultipleStreams_) {
            decompressor.SetAllowMultipleStreams(false);
        }
        decodedContent = decompressor.ReadAll();
    } else if (ContentEncoding_ == "deflate") {

        //https://tools.ietf.org/html/rfc1950
        bool definitelyNoZlibHeader;
        if (Content_.size() < 2) {
            definitelyNoZlibHeader = true;
        } else {
            const ui16 cmf = static_cast<ui8>(Content_[0]);
            const ui16 flg = static_cast<ui8>(Content_[1]);
            definitelyNoZlibHeader = ((cmf << 8) | flg) % 31 != 0;
        }

        try {
            decodedContent = TZLibDecompress(&in, definitelyNoZlibHeader ? ZLib::Raw : ZLib::ZLib).ReadAll();
        }
        catch(...) {
            if (definitelyNoZlibHeader) {
                throw;
            }
            TMemoryInput retryInput(Content_.data(), Content_.size());
            decodedContent = TZLibDecompress(&retryInput, ZLib::Raw).ReadAll();
        }
    } else if (ContentEncoding_.StartsWith("z-")) {
        // opposite for library/cpp/http/io/stream.h
        const NBlockCodecs::ICodec* codec = nullptr;
        try {
            const TStringBuf codecName = TStringBuf(ContentEncoding_).SubStr(2);
            if (codecName.StartsWith("zstd06") || codecName.StartsWith("zstd08")) {
                ythrow NBlockCodecs::TNotFound() << codecName;
            }
            codec = NBlockCodecs::Codec(codecName);
        } catch(const NBlockCodecs::TNotFound& exc) {
            throw THttpParseException() << "Unsupported content-encoding method: " << exc.AsStrBuf();
        }
        NBlockCodecs::TDecodedInput decoder(&in, codec);
        decodedContent = decoder.ReadAll();
    } else if (ContentEncoding_ == "lz4") {
        const auto* codec = NBlockCodecs::Codec(TStringBuf(ContentEncoding_));
        decodedContent = codec->Decode(Content_);
    } else if (ContentEncoding_ == "br") {
        TBrotliDecompress decoder(&in);
        decodedContent = decoder.ReadAll();
    } else {
        throw THttpParseException() << "Unsupported content-encoding method: " << ContentEncoding_;
    }