src/HTTPHandler.h
author František Kučera <franta-hg@frantovo.cz>
Sun, 06 Mar 2022 22:01:32 +0100
branchv_0
changeset 3 9c710397ced6
parent 2 dccedac46e7e
child 4 602462d04c57
permissions -rw-r--r--
return also the HTTP response code and URL

/**
 * Relational pipes
 * Copyright © 2020 František Kučera (Frantovo.cz, GlobalCode.info)
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, version 3 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
#pragma once

#include <memory>
#include <string>
#include <vector>
#include <codecvt>
#include <regex>
#include <stdexcept>

#include <curl/curl.h>

#include <relpipe/common/type/typedefs.h>
#include <relpipe/reader/TypeId.h>
#include <relpipe/reader/handlers/RelationalReaderStringHandler.h>
#include <relpipe/reader/handlers/AttributeMetadata.h>

#include <relpipe/writer/Factory.h>
#include <relpipe/writer/TypeId.h>

#include <relpipe/cli/RelpipeCLIException.h>

#include "Configuration.h"

namespace relpipe {
namespace tr {
namespace http {

class HTTPHandler : public relpipe::reader::handlers::RelationalReaderStringHandler {
private:
	std::wstring_convert<codecvt_utf8<wchar_t>> convertor; // TODO: support also other encodings.
	shared_ptr<relpipe::writer::RelationalWriter> relationalWriter;
	Configuration configuration;
	std::vector<relpipe::reader::handlers::AttributeMetadata> currentReaderMetadata;
	std::vector<relpipe::writer::AttributeMetadata> currentWriterMetadata;
	size_t currentAttributeIndex = 0;
	size_t currentRecordNumber = 1;

	void writeCallback(std::string value) {
		// TODO: write this attribute even if this method was not called
		// TODO: support also binary data or other encodings, not only UTF-8 text
		relationalWriter->writeAttribute(convertor.from_bytes(value));
	}

	static uint writeCurlCallback(char* buffer, size_t size, size_t nmemb, HTTPHandler* instance) {
		size_t r = size * nmemb;
		instance->writeCallback(std::string(buffer, r));
		return r;
	}

public:

	HTTPHandler(shared_ptr<relpipe::writer::RelationalWriter> relationalWriter, Configuration configuration) : relationalWriter(relationalWriter), configuration(configuration) {
	}

	virtual ~HTTPHandler() {
	}

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


		relationalWriter->startRelation(name + L"_curl_info",{
			{L"name", relpipe::writer::TypeId::STRING},
			{L"value", relpipe::writer::TypeId::STRING}
		}, true);

		relationalWriter->writeAttribute(L"curl version");
		relationalWriter->writeAttribute(convertor.from_bytes(curl_version()));

		relationalWriter->startRelation(name + L"_curl_response",{
			{L"url", relpipe::writer::TypeId::STRING},
			{L"body", relpipe::writer::TypeId::STRING},
			{L"response_code", relpipe::writer::TypeId::INTEGER}
		}, true);

	}

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

		relationalWriter->writeAttribute(value);

		std::string url = convertor.to_bytes(value);
		relpipe::common::type::Integer responseCode = 0;

		CURL* curl = curl_easy_init();
		curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
		curl_easy_setopt(curl, CURLOPT_WRITEDATA, this);
		curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, writeCurlCallback);
		curl_easy_perform(curl);
		curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &responseCode);
		curl_easy_cleanup(curl);

		relationalWriter->writeAttribute(&responseCode, typeid (responseCode));
	}

	void endOfPipe() {

	}

};

}
}
}