1 /**

     2  * Relational pipes

     3  * Copyright © 2022 František Kučera (Frantovo.cz, GlobalCode.info)

     4  *

     5  * This program is free software: you can redistribute it and/or modify

     6  * it under the terms of the GNU General Public License as published by

     7  * the Free Software Foundation, version 3 of the License.

     8  *

     9  * This program is distributed in the hope that it will be useful,

    10  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

    12  * GNU General Public License for more details.

    13  *

    14  * You should have received a copy of the GNU General Public License

    15  * along with this program. If not, see <http://www.gnu.org/licenses/>.

    16  */

    17 #pragma once

    18 

    19 #include <memory>

    20 #include <string>

    21 #include <vector>

    22 #include <iostream>

    23 #include <sstream>

    24 #include <locale>

    25 #include <codecvt>

    26 

    27 #include <relpipe/common/type/typedefs.h>

    28 #include <relpipe/reader/TypeId.h>

    29 #include <relpipe/reader/handlers/RelationalReaderStringHandler.h>

    30 #include <relpipe/reader/handlers/AttributeMetadata.h>

    31 

    32 #include "Kafka.h"

    33 #include "Configuration.h"

    34 #include "Hex.h"

    35 

    36 namespace relpipe {

    37 namespace out {

    38 namespace kafka {

    39 

    40 class KafkaHandler : public relpipe::reader::handlers::RelationalReaderStringHandler {

    41 private:

    42 	std::wstring_convert<codecvt_utf8<wchar_t>> convertor; // TODO: support also other encodings.

    43 	Configuration configuration;

    44 	shared_ptr<Kafka> mq;

    45 

    46 	struct CurrentRelation {

    47 		relpipe::common::type::StringX name;

    48 		std::vector<relpipe::reader::handlers::AttributeMetadata> attributes;

    49 		relpipe::common::type::Integer attributeIndex = 0;

    50 		std::string currentValue;

    51 	} currentRelation;

    52 

    53 public:

    54 

    55 	KafkaHandler(Configuration configuration) : configuration(configuration) {

    56 		mq.reset(Kafka::open(convertor.to_bytes(configuration.queue), configuration.unlinkOnClose));

    57 	}

    58 

    59 	void startRelation(relpipe::common::type::StringX name, std::vector<relpipe::reader::handlers::AttributeMetadata> attributes) override {

    60 		currentRelation = CurrentRelation{name, attributes};

    61 	}

    62 

    63 	void attribute(const relpipe::common::type::StringX& value) override {

    64 

    65 		auto attributeName = currentRelation.attributes[currentRelation.attributeIndex].getAttributeName();

    66 		if (attributeName == L"text") currentRelation.currentValue = convertor.to_bytes(value);

    67 		else if (attributeName == L"data") currentRelation.currentValue = Hex::fromHex(value).str();

    68 

    69 		currentRelation.attributeIndex++;

    70 		if (currentRelation.attributeIndex == currentRelation.attributes.size()) {

    71 			currentRelation.attributeIndex = 0;

    72 			mq->send(currentRelation.currentValue);

    73 		}

    74 

    75 	}

    76 

    77 	void endOfPipe() {

    78 

    79 	}

    80 

    81 };

    82 

    83 }

    84 }

    85 }