io.streamthoughts.azkarra.api.query.internal.SessionFetchKeyRangeQuery Maven / Gradle / Ivy

Go to download
/*
 * Copyright 2019-2020 StreamThoughts.
 *
 * 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.
 */
package io.streamthoughts.azkarra.api.query.internal;

import io.streamthoughts.azkarra.api.model.KV;
import io.streamthoughts.azkarra.api.monad.Reader;
import io.streamthoughts.azkarra.api.monad.Try;
import io.streamthoughts.azkarra.api.query.DecorateQuery;
import io.streamthoughts.azkarra.api.query.GenericQueryParams;
import io.streamthoughts.azkarra.api.query.LocalExecutableQuery;
import io.streamthoughts.azkarra.api.query.LocalStoreAccessProvider;
import io.streamthoughts.azkarra.api.query.LocalStoreAccessor;
import io.streamthoughts.azkarra.api.query.Query;
import io.streamthoughts.azkarra.api.query.QueryRequest;
import io.streamthoughts.azkarra.api.query.StoreOperation;
import io.streamthoughts.azkarra.api.query.StoreType;
import org.apache.kafka.streams.kstream.Windowed;
import org.apache.kafka.streams.state.KeyValueIterator;
import org.apache.kafka.streams.state.ReadOnlySessionStore;

import java.util.List;

public class SessionFetchKeyRangeQuery
        extends DecorateQuery
        implements LocalExecutableQuery, V> {

    private final K keyFrom;
    private final K keyTo;

    /**
     * Creates a new {@link KeyValueGetRangeQuery} instance.
     *
     * @param store         the name of the store.
     * @param keyFrom       the keyFrom
     * @param keyTo         the keyTo
     */
    SessionFetchKeyRangeQuery(final String store, final K keyFrom, final K keyTo) {
        super(new QueryRequest()
                .storeName(store)
                .storeType(StoreType.SESSION)
                .storeOperation(StoreOperation.RANGE)
                .params(new GenericQueryParams()
                        .put(QueryConstants.QUERY_PARAM_KEY_FROM, keyFrom)
                        .put(QueryConstants.QUERY_PARAM_KEY_TO, keyTo)
                )
        );
        this.keyFrom = keyFrom;
        this.keyTo = keyTo;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public Try, V>>>  execute(final LocalStoreAccessProvider provider, final long limit) {

        final LocalStoreAccessor> accessor = provider.localSessionStore(getStoreName());

        final Reader, List, V>>> reader =
            reader(keyFrom, keyTo)
           .map(iterator -> LocalExecutableQuery.toKeyValueListAndClose(iterator, limit));

        return new LocalStoreQueryExecutor<>(accessor).execute(reader);
    }

    private Reader, KeyValueIterator, V>> reader(final K keyFrom,
                                                                                        final K keyTo) {
        return Reader.of(store -> store.fetch(keyFrom, keyTo));
    }
}