/*
 * Copyright 2012-2020 the original author or authors.
 *
 * Licensed 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
 *
 *      https://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 org.springframework.boot.actuate.cassandra;

import com.datastax.oss.driver.api.core.ConsistencyLevel;
import com.datastax.oss.driver.api.core.cql.SimpleStatement;

import org.springframework.boot.actuate.health.AbstractHealthIndicator;
import org.springframework.boot.actuate.health.Health;
import org.springframework.boot.actuate.health.HealthIndicator;
import org.springframework.data.cassandra.core.CassandraOperations;
import org.springframework.util.Assert;

Simple implementation of a HealthIndicator returning status information for Cassandra data stores. 
Author:
Julien Dubois, Alexandre Dutra
Since:
2.0.0/**
 * Simple implementation of a {@link HealthIndicator} returning status information for
 * Cassandra data stores.
 *
 * @author Julien Dubois
 * @author Alexandre Dutra
 * @since 2.0.0
 */
public class CassandraHealthIndicator extends AbstractHealthIndicator {

	private static final SimpleStatement SELECT = SimpleStatement
			.newInstance("SELECT release_version FROM system.local").setConsistencyLevel(ConsistencyLevel.LOCAL_ONE);

	private CassandraOperations cassandraOperations;

	public CassandraHealthIndicator() {
		super("Cassandra health check failed");
	}

	
Create a new CassandraHealthIndicator instance. 
Params:
cassandraOperations – the Cassandra operations/**
	 * Create a new {@link CassandraHealthIndicator} instance.
	 * @param cassandraOperations the Cassandra operations
	 */
	public CassandraHealthIndicator(CassandraOperations cassandraOperations) {
		super("Cassandra health check failed");
		Assert.notNull(cassandraOperations, "CassandraOperations must not be null");
		this.cassandraOperations = cassandraOperations;
	}

	@Override
	protected void doHealthCheck(Health.Builder builder) throws Exception {
		String version = this.cassandraOperations.getCqlOperations().queryForObject(SELECT, String.class);
		builder.up().withDetail("version", version);
	}

}