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/* * Copyright 2015 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 * * 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 org.springframework.cloud.stream.app.jdbc.sink; import java.util.List; import java.util.Map; import java.util.Set; import javax.annotation.PostConstruct; import javax.sql.DataSource; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.beans.DirectFieldAccessor; import org.springframework.beans.factory.BeanFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty; import org.springframework.boot.context.properties.ConfigurationPropertiesBinding; import org.springframework.boot.context.properties.EnableConfigurationProperties; import org.springframework.cloud.stream.annotation.EnableBinding; import org.springframework.cloud.stream.messaging.Sink; import org.springframework.context.annotation.Bean; import org.springframework.core.io.ResourceLoader; import org.springframework.expression.EvaluationContext; import org.springframework.expression.EvaluationException; import org.springframework.expression.Expression; import org.springframework.expression.spel.standard.SpelExpressionParser; import org.springframework.integration.annotation.ServiceActivator; import org.springframework.integration.expression.ExpressionUtils; import org.springframework.integration.jdbc.JdbcMessageHandler; import org.springframework.integration.jdbc.SqlParameterSourceFactory; import org.springframework.integration.json.JsonPropertyAccessor; import org.springframework.jdbc.core.namedparam.MapSqlParameterSource; import org.springframework.jdbc.core.namedparam.SqlParameterSource; import org.springframework.jdbc.datasource.init.DataSourceInitializer; import org.springframework.jdbc.datasource.init.ResourceDatabasePopulator; import org.springframework.messaging.Message; import org.springframework.util.LinkedMultiValueMap; import org.springframework.util.MultiValueMap; import com.fasterxml.jackson.databind.JsonNode; /** * A module that writes its incoming payload to an RDBMS using JDBC. * * @author Eric Bottard * @author Thomas Risberg */ @EnableBinding(Sink.class) @EnableConfigurationProperties(JdbcSinkProperties.class) public class JdbcSinkConfiguration { private static final Log logger = LogFactory.getLog(JdbcSinkConfiguration.class); public static final Object NOT_SET = new Object(); private SpelExpressionParser spelExpressionParser = new SpelExpressionParser(); @Autowired private BeanFactory beanFactory; protected EvaluationContext evaluationContext; @Autowired private JdbcSinkProperties properties; @Bean @ServiceActivator(autoStartup = "false", inputChannel = Sink.INPUT) public JdbcMessageHandler jdbcMessageHandler(DataSource dataSource) { final MultiValueMap<String, Expression> columnExpressionVariations = new LinkedMultiValueMap<>(); for (Map.Entry<String, String> entry : properties.getColumns().entrySet()) { String value = entry.getValue(); columnExpressionVariations.add(entry.getKey(), spelExpressionParser.parseExpression(value)); if (!value.startsWith("payload")) { columnExpressionVariations.add(entry.getKey(), spelExpressionParser.parseExpression("payload." + value)); } } JdbcMessageHandler jdbcMessageHandler = new JdbcMessageHandler(dataSource, generateSql(properties.getTableName(), columnExpressionVariations.keySet())); jdbcMessageHandler.setSqlParameterSourceFactory(new SqlParameterSourceFactory() { @Override public SqlParameterSource createParameterSource(Object o) { if (!(o instanceof Message)) { throw new IllegalArgumentException("Unable to handle type " + o.getClass().getName()); } Message<?> message = (Message<?>) o; MapSqlParameterSource parameterSource = new MapSqlParameterSource(); for (String key : columnExpressionVariations.keySet()) { List<Expression> spels = columnExpressionVariations.get(key); Object value = NOT_SET; EvaluationException lastException = null; for (Expression spel : spels) { try { value = spel.getValue(evaluationContext, message); break; } catch (EvaluationException e) { lastException = e; } } if (value == NOT_SET) { if (lastException != null) { logger.info( "Could not find value for column '" + key + "': " + lastException.getMessage()); } parameterSource.addValue(key, null); } else { if (value instanceof JsonPropertyAccessor.ToStringFriendlyJsonNode) { // Need to do some reflection until we have a getter for the Node DirectFieldAccessor dfa = new DirectFieldAccessor(value); JsonNode node = (JsonNode) dfa.getPropertyValue("node"); Object valueToUse; if (node == null || node.isNull()) { valueToUse = null; } else if (node.isNumber()) { valueToUse = node.numberValue(); } else if (node.isBoolean()) { valueToUse = node.booleanValue(); } else { valueToUse = node.textValue(); } parameterSource.addValue(key, valueToUse); } else { parameterSource.addValue(key, value); } } } return parameterSource; } }); return jdbcMessageHandler; } @ConditionalOnProperty("jdbc.initialize") @Bean public DataSourceInitializer nonBootDataSourceInitializer(DataSource dataSource, ResourceLoader resourceLoader) { DataSourceInitializer dataSourceInitializer = new DataSourceInitializer(); dataSourceInitializer.setDataSource(dataSource); ResourceDatabasePopulator databasePopulator = new ResourceDatabasePopulator(); databasePopulator.setIgnoreFailedDrops(true); dataSourceInitializer.setDatabasePopulator(databasePopulator); if ("true".equals(properties.getInitialize())) { databasePopulator.addScript(new DefaultInitializationScriptResource(properties)); } else { databasePopulator.addScript(resourceLoader.getResource(properties.getInitialize())); } return dataSourceInitializer; } /* * This is needed to prevent a circular dependency issue with the creation of the converter. */ public static class Nested { @Bean @ConfigurationPropertiesBinding public ShorthandMapConverter shorthandMapConverter() { return new ShorthandMapConverter(); } } @PostConstruct public void afterPropertiesSet() { this.evaluationContext = ExpressionUtils.createStandardEvaluationContext(beanFactory); } private String generateSql(String tableName, Set<String> columns) { StringBuilder builder = new StringBuilder("INSERT INTO "); StringBuilder questionMarks = new StringBuilder(") VALUES ("); builder.append(tableName).append("("); int i = 0; for (String column : columns) { if (i++ > 0) { builder.append(", "); questionMarks.append(", "); } builder.append(column); questionMarks.append(':' + column); } builder.append(questionMarks).append(")"); return builder.toString(); } }