Method queryResultsCSV

cpp_src/server/httpserver.cc:1615–1682

}

int HTTPServer::queryResultsCSV(http::Context& ctx, reindexer::QueryResults& res, const IQRSerializingOption& qrOption) {
	if (!res.GetAggregationResults().empty()) {
		throw Error(errForbidden, "Aggregations are not supported in CSV");
	}
	if (!res.GetExplainResults().empty()) {
		throw Error(errForbidden, "Explain is not supported in CSV");
	}

	const size_t kChunkMaxSize = 0x1000;
	auto createChunk = [](const WrSerializer& from, WrSerializer& to) {
		char szBuf[64];
		size_t l = u32toax(from.Len(), szBuf) - szBuf;
		to << std::string_view(szBuf, l);
		to << "\r\n";
		to << from.Slice();
		to << "\r\n";
	};

	auto createCSVHeaders = [&res](WrSerializer& ser, const CsvOrdering& ordering) {
		const auto& tm = res.GetTagsMatcher(0);
		for (auto it = ordering.begin(); it != ordering.end(); ++it) {
			if (it != ordering.begin()) {
				ser << ',';
			}
			ser << tm.tag2name(*it);
		}
		if (res.ToLocalQr().joined_.empty()) {
			ser << "\n";
		} else {
			ser << ",joined_namespaces\n";
		}
	};

	auto wrSerRes = makeRestrictedWrSerializer(ctx);
	WrSerializer wrSerChunk;
	const auto schema = res.GetSchema(0);
	const bool withSchema = schema && !schema->IsEmpty();
	if (!res.IsLocal() && !withSchema) {
		throw Error(errLogic, "Uploads in csv format without a namespace scheme are allowed only for local queries");
	}

	const auto limit = qrOption.ExternalLimit();
	const auto offset = qrOption.ExternalOffset();
	auto ordering =
		withSchema ? CsvOrdering{schema->MakeCsvTagOrdering(res.GetTagsMatcher(0))} : res.ToLocalQr().MakeCSVTagOrdering(limit, offset);

	createCSVHeaders(wrSerChunk, ordering);
	auto it = res.begin() + offset;
	for (size_t i = 0; it != res.end() && i < limit; ++i, ++it) {
		auto err = it.GetCSV(wrSerChunk, ordering);
		if (!err.ok()) {
			throw Error(err.code(), "Unable to get {} item as CSV: {}", i, err.whatStr());
		}

		wrSerChunk << '\n';

		if (wrSerChunk.Len() > kChunkMaxSize) {
			createChunk(wrSerChunk, wrSerRes);