ClickHouse/src/Storages/StorageMongoDB.cpp

#include <Storages/StorageMongoDB.h>
#include <Storages/StorageMongoDBSocketFactory.h>
#include <Storages/StorageFactory.h>
#include <Storages/checkAndGetLiteralArgument.h>
#include <Storages/NamedCollectionsHelpers.h>

#include <Poco/MongoDB/Connection.h>
#include <Poco/MongoDB/Cursor.h>
#include <Poco/MongoDB/Database.h>
#include <Poco/Version.h>
#include <Interpreters/evaluateConstantExpression.h>
#include <Core/Settings.h>
#include <Interpreters/Context.h>
#include <Common/parseAddress.h>
#include <Common/NamedCollections/NamedCollections.h>
#include <IO/Operators.h>
#include <Parsers/ASTLiteral.h>
#include <QueryPipeline/Pipe.h>
#include <Processors/Transforms/MongoDBSource.h>
#include <Processors/Sinks/SinkToStorage.h>

namespace DB
{

namespace ErrorCodes
{
    extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
    extern const int MONGODB_CANNOT_AUTHENTICATE;
}

StorageMongoDB::StorageMongoDB(
    const StorageID & table_id_,
    const std::string & host_,
    uint16_t port_,
    const std::string & database_name_,
    const std::string & collection_name_,
    const std::string & username_,
    const std::string & password_,
    const std::string & options_,
    const ColumnsDescription & columns_,
    const ConstraintsDescription & constraints_,
    const String & comment)
    : IStorage(table_id_)
    , database_name(database_name_)
    , collection_name(collection_name_)
    , username(username_)
    , password(password_)
    , uri("mongodb://" + host_ + ":" + std::to_string(port_) + "/" + database_name_ + "?" + options_)
{
    StorageInMemoryMetadata storage_metadata;
    storage_metadata.setColumns(columns_);
    storage_metadata.setConstraints(constraints_);
    storage_metadata.setComment(comment);
    setInMemoryMetadata(storage_metadata);
}


void StorageMongoDB::connectIfNotConnected()
{
    std::lock_guard lock{connection_mutex};
    if (!connection)
    {
        StorageMongoDBSocketFactory factory;
        connection = std::make_shared<Poco::MongoDB::Connection>(uri, factory);
    }

    if (!authenticated)
    {
        Poco::URI poco_uri(uri);
        auto query_params = poco_uri.getQueryParameters();
        auto auth_source = std::find_if(query_params.begin(), query_params.end(),
                                        [&](const std::pair<std::string, std::string> & param) { return param.first == "authSource"; });
        auto auth_db = database_name;
        if (auth_source != query_params.end())
            auth_db = auth_source->second;

        if (!username.empty() && !password.empty())
        {
            Poco::MongoDB::Database poco_db(auth_db);
            if (!poco_db.authenticate(*connection, username, password, Poco::MongoDB::Database::AUTH_SCRAM_SHA1))
                throw Exception("Cannot authenticate in MongoDB, incorrect user or password", ErrorCodes::MONGODB_CANNOT_AUTHENTICATE);
        }

        authenticated = true;
    }
}


class StorageMongoDBSink : public SinkToStorage
{
public:
    explicit StorageMongoDBSink(
        const std::string & collection_name_,
        const std::string & db_name_,
        const StorageMetadataPtr & metadata_snapshot_,
        std::shared_ptr<Poco::MongoDB::Connection> connection_)
        : SinkToStorage(metadata_snapshot_->getSampleBlock())
        , collection_name(collection_name_)
        , db_name(db_name_)
        , metadata_snapshot{metadata_snapshot_}
        , connection(connection_)
    {
    }

    String getName() const override { return "StorageMongoDBSink"; }

    void consume(Chunk chunk) override
    {
        Poco::MongoDB::Database db(db_name);
        Poco::MongoDB::Document::Ptr index = new Poco::MongoDB::Document();

        auto block = getHeader().cloneWithColumns(chunk.detachColumns());

        size_t num_rows = block.rows();
        size_t num_cols = block.columns();

        const auto columns = block.getColumns();
        const auto data_types = block.getDataTypes();
        const auto data_names = block.getNames();

        std::vector<std::string> row(num_cols);
        for (const auto i : collections::range(0, num_rows))
        {
            for (const auto j : collections::range(0, num_cols))
            {
                WriteBufferFromOwnString ostr;
                data_types[j]->getDefaultSerialization()->serializeText(*columns[j], i, ostr, FormatSettings{});
                row[j] = ostr.str();
                index->add(data_names[j], row[j]);
            }
        }
        Poco::SharedPtr<Poco::MongoDB::InsertRequest> insert_request = db.createInsertRequest(collection_name);
        insert_request->documents().push_back(index);
        connection->sendRequest(*insert_request);
    }

private:
    String collection_name;
    String db_name;
    StorageMetadataPtr metadata_snapshot;
    std::shared_ptr<Poco::MongoDB::Connection> connection;
};


Pipe StorageMongoDB::read(
    const Names & column_names,
    const StorageSnapshotPtr & storage_snapshot,
    SelectQueryInfo & /*query_info*/,
    ContextPtr /*context*/,
    QueryProcessingStage::Enum /*processed_stage*/,
    size_t max_block_size,
    size_t /*num_streams*/)
{
    connectIfNotConnected();

    storage_snapshot->check(column_names);

    Block sample_block;
    for (const String & column_name : column_names)
    {
        auto column_data = storage_snapshot->metadata->getColumns().getPhysical(column_name);
        sample_block.insert({ column_data.type, column_data.name });
    }

    return Pipe(std::make_shared<MongoDBSource>(connection, createCursor(database_name, collection_name, sample_block), sample_block, max_block_size));
}

SinkToStoragePtr StorageMongoDB::write(const ASTPtr & /* query */, const StorageMetadataPtr & metadata_snapshot, ContextPtr /* context */)
{
    connectIfNotConnected();
    return std::make_shared<StorageMongoDBSink>(collection_name, database_name, metadata_snapshot, connection);
}

struct KeysCmp
{
    constexpr bool operator()(const auto & lhs, const auto & rhs) const
    {
        return lhs == rhs || ((lhs == "table") && (rhs == "collection")) || ((rhs == "table") && (lhs == "collection"));
    }
};
StorageMongoDB::Configuration StorageMongoDB::getConfiguration(ASTs engine_args, ContextPtr context)
{
    Configuration configuration;

    if (auto named_collection = tryGetNamedCollectionWithOverrides(engine_args))
    {
        validateNamedCollection(
            *named_collection,
            std::unordered_multiset<std::string_view, std::hash<std::string_view>, KeysCmp>{"host", "port", "user", "password", "database", "collection", "table"},
            {"options"});

        configuration.host = named_collection->get<String>("host");
        configuration.port = static_cast<UInt16>(named_collection->get<UInt64>("port"));
        configuration.username = named_collection->get<String>("user");
        configuration.password = named_collection->get<String>("password");
        configuration.database = named_collection->get<String>("database");
        configuration.table = named_collection->getOrDefault<String>("collection", named_collection->getOrDefault<String>("table", ""));
        configuration.options = named_collection->getOrDefault<String>("options", "");
    }
    else
    {
        if (engine_args.size() < 5 || engine_args.size() > 6)
            throw Exception(
                "Storage MongoDB requires from 5 to 6 parameters: MongoDB('host:port', database, collection, 'user', 'password' [, 'options']).",
                ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);

        for (auto & engine_arg : engine_args)
            engine_arg = evaluateConstantExpressionOrIdentifierAsLiteral(engine_arg, context);

        /// 27017 is the default MongoDB port.
        auto parsed_host_port = parseAddress(checkAndGetLiteralArgument<String>(engine_args[0], "host:port"), 27017);

        configuration.host = parsed_host_port.first;
        configuration.port = parsed_host_port.second;
        configuration.database = checkAndGetLiteralArgument<String>(engine_args[1], "database");
        configuration.table = checkAndGetLiteralArgument<String>(engine_args[2], "table");
        configuration.username = checkAndGetLiteralArgument<String>(engine_args[3], "username");
        configuration.password = checkAndGetLiteralArgument<String>(engine_args[4], "password");

        if (engine_args.size() >= 6)
            configuration.options = checkAndGetLiteralArgument<String>(engine_args[5], "database");
    }

    context->getRemoteHostFilter().checkHostAndPort(configuration.host, toString(configuration.port));

    return configuration;
}


void registerStorageMongoDB(StorageFactory & factory)
{
    factory.registerStorage("MongoDB", [](const StorageFactory::Arguments & args)
    {
        auto configuration = StorageMongoDB::getConfiguration(args.engine_args, args.getLocalContext());

        return std::make_shared<StorageMongoDB>(
            args.table_id,
            configuration.host,
            configuration.port,
            configuration.database,
            configuration.table,
            configuration.username,
            configuration.password,
            configuration.options,
            args.columns,
            args.constraints,
            args.comment);
    },
    {
        .source_access_type = AccessType::MONGO,
    });
}

}