ClickHouse/dbms/src/Storages/System/StorageSystemClusters.cpp

#include <Common/DNSResolver.h>
#include <DataTypes/DataTypeString.h>
#include <DataTypes/DataTypesNumber.h>
#include <Interpreters/Cluster.h>
#include <Interpreters/Context.h>
#include <Storages/System/StorageSystemClusters.h>

namespace DB
{

NamesAndTypesList StorageSystemClusters::getNamesAndTypes()
{
    return
    {
        {"cluster", std::make_shared<DataTypeString>()},
        {"shard_num", std::make_shared<DataTypeUInt32>()},
        {"shard_weight", std::make_shared<DataTypeUInt32>()},
        {"replica_num", std::make_shared<DataTypeUInt32>()},
        {"host_name", std::make_shared<DataTypeString>()},
        {"host_address", std::make_shared<DataTypeString>()},
        {"port", std::make_shared<DataTypeUInt16>()},
        {"is_local", std::make_shared<DataTypeUInt8>()},
        {"user", std::make_shared<DataTypeString>()},
        {"default_database", std::make_shared<DataTypeString>()},
    };
}

void StorageSystemClusters::fillData(MutableColumns & res_columns, const Context & context, const SelectQueryInfo &) const
{
    for (const auto & name_and_cluster : context.getClusters().getContainer())
    {
        const String & cluster_name = name_and_cluster.first;
        const ClusterPtr & cluster = name_and_cluster.second;
        const auto & shards_info = cluster->getShardsInfo();
        const auto & addresses_with_failover = cluster->getShardsAddresses();

        for (size_t shard_index = 0; shard_index < shards_info.size(); ++shard_index)
        {
            const auto & shard_info = shards_info[shard_index];
            const auto & shard_addresses = addresses_with_failover[shard_index];

            for (size_t replica_index = 0; replica_index < shard_addresses.size(); ++replica_index)
            {
                size_t i = 0;
                const auto & address = shard_addresses[replica_index];

                res_columns[i++]->insert(cluster_name);
                res_columns[i++]->insert(shard_info.shard_num);
                res_columns[i++]->insert(shard_info.weight);
                res_columns[i++]->insert(replica_index + 1);
                res_columns[i++]->insert(address.host_name);
                auto resolved = address.getResolvedAddress();
                res_columns[i++]->insert(resolved ? resolved->host().toString() : String());
                res_columns[i++]->insert(address.port);
                res_columns[i++]->insert(shard_info.isLocal());
                res_columns[i++]->insert(address.user);
                res_columns[i++]->insert(address.default_database);
            }
        }
    }
}
}