pulsar-client-cpp/lib/HTTPLookupService.h

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
#ifndef PULSAR_CPP_HTTPLOOKUPSERVICE_H
#define PULSAR_CPP_HTTPLOOKUPSERVICE_H

#include <lib/LookupService.h>
#include <lib/ClientImpl.h>
#include <lib/Url.h>
#include <json/value.h>
#include <json/reader.h>
#include <boost/bind.hpp>
#include <curl/curl.h>
#include <lib/Version.h>

namespace pulsar {
    class HTTPLookupService : public LookupService, public boost::enable_shared_from_this<HTTPLookupService> {
        class CurlInitializer {
         public:
            CurlInitializer() {
                // Once per application - https://curl.haxx.se/mail/lib-2015-11/0052.html
                curl_global_init (CURL_GLOBAL_ALL);
            }
            ~CurlInitializer() {
                curl_global_cleanup();
            }
        };
        static CurlInitializer curlInitializer;
        enum RequestType {Lookup, PartitionMetaData};
        typedef Promise<Result, LookupDataResultPtr> LookupPromise;
        ExecutorServiceProviderPtr executorProvider_;
        std::string adminUrl_;
        AuthenticationPtr authenticationPtr_;
        int lookupTimeoutInSeconds_;

        static LookupDataResultPtr parsePartitionData(const std::string&);
        static LookupDataResultPtr parseLookupData(const std::string&);
        void sendHTTPRequest(LookupPromise, const std::string, RequestType);
     public:
        HTTPLookupService(const std::string&, const ClientConfiguration&, const AuthenticationPtr&);

        Future<Result, LookupDataResultPtr> lookupAsync(const std::string&);

        Future<Result, LookupDataResultPtr> getPartitionMetadataAsync(const DestinationNamePtr&);
    };

}

#endif //PULSAR_CPP_HTTPLOOKUPSERVICE_H