content: package com.alibaba.otter.canal.client.adapter.rdb.service;
  
  import java.sql.Connection;
  import java.sql.ResultSetMetaData;
  import java.sql.SQLException;
  import java.sql.Types;
  import java.util.ArrayList;
  import java.util.LinkedHashMap;
  import java.util.List;
  import java.util.Map;
  import java.util.Properties;
  import java.util.concurrent.ConcurrentHashMap;
  import java.util.concurrent.ExecutionException;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.Executors;
  import java.util.concurrent.Future;
  import java.util.function.Function;
  
  import org.apache.commons.lang.StringUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import com.alibaba.druid.pool.DruidDataSource;
  import com.alibaba.fastjson2.JSON;
  import com.alibaba.fastjson2.JSONWriter.Feature;
  import com.alibaba.otter.canal.client.adapter.rdb.config.MappingConfig;
  import com.alibaba.otter.canal.client.adapter.rdb.config.MappingConfig.DbMapping;
  import com.alibaba.otter.canal.client.adapter.rdb.support.BatchExecutor;
  import com.alibaba.otter.canal.client.adapter.rdb.support.SingleDml;
  import com.alibaba.otter.canal.client.adapter.rdb.support.SyncUtil;
  import com.alibaba.otter.canal.client.adapter.support.Dml;
  import com.alibaba.otter.canal.client.adapter.support.Util;
  
  /**
   * RDB同步操作业务
   *
   * @author rewerma 2018-11-7 下午06:45:49
   * @version 1.0.0
   */
  public class RdbSyncService {
  
      private static final Logger               logger  = LoggerFactory.getLogger(RdbSyncService.class);
  
      private DruidDataSource                   dataSource;
      // 源库表字段类型缓存: instance.schema.table -> <columnName, jdbcType>
      private Map<String, Map<String, Integer>> columnsTypeCache;
  
      private int                               threads = 3;
      private boolean                           skipDupException;
  
      private List<SyncItem>[]                  dmlsPartition;
      private BatchExecutor[]                   batchExecutors;
      private ExecutorService[]                 executorThreads;
  
      public List<SyncItem>[] getDmlsPartition() {
          return dmlsPartition;
      }
  
      public Map<String, Map<String, Integer>> getColumnsTypeCache() {
          return columnsTypeCache;
      }
  
      public RdbSyncService(DruidDataSource dataSource, Integer threads, boolean skipDupException){
          this(dataSource, threads, new ConcurrentHashMap<>(), skipDupException);
      }
  
      @SuppressWarnings("unchecked")
      public RdbSyncService(DruidDataSource dataSource, Integer threads, Map<String, Map<String, Integer>> columnsTypeCache,
                            boolean skipDupException){
          this.dataSource = dataSource;
          this.columnsTypeCache = columnsTypeCache;
          this.skipDupException = skipDupException;
          try {
              if (threads != null) {
                  this.threads = threads;
              }
              this.dmlsPartition = new List[this.threads];
              this.batchExecutors = new BatchExecutor[this.threads];
              this.executorThreads = new ExecutorService[this.threads];
              for (int i = 0; i < this.threads; i++) {
                  dmlsPartition[i] = new ArrayList<>();
                  batchExecutors[i] = new BatchExecutor(dataSource);
                  executorThreads[i] = Executors.newSingleThreadExecutor();
              }
          } catch (Exception e) {
              throw new RuntimeException(e);
          }
      }
  
      /**
       * 批量同步回调
       *
       * @param dmls 批量 DML
       * @param function 回调方法
       */
      public void sync(List<Dml> dmls, Function<Dml, Boolean> function) {
          try {
              boolean toExecute = false;
              for (Dml dml : dmls) {
                  if (!toExecute) {
                      toExecute = function.apply(dml);
                  } else {
                      function.apply(dml);
                  }
              }
              if (toExecute) {
                  List<Future<Boolean>> futures = new ArrayList<>();
                  for (int i = 0; i < threads; i++) {
                      int j = i;
                      if (dmlsPartition[j].isEmpty()) {
                          // bypass
                          continue;
                      }
  
                      futures.add(executorThreads[i].submit(() -> {
                          try {
                              dmlsPartition[j].forEach(syncItem -> sync(batchExecutors[j],
                                  syncItem.config,
                                  syncItem.singleDml));
                              dmlsPartition[j].clear();
                              batchExecutors[j].commit();
                              return true;
                          } catch (Throwable e) {
                              dmlsPartition[j].clear();
                              batchExecutors[j].rollback();
                              throw new RuntimeException(e);
                          }
                      }));
                  }
  
                  futures.forEach(future -> {
                      try {
                          future.get();
                      } catch (ExecutionException | InterruptedException e) {
                          throw new RuntimeException(e);
                      }
                  });
              }
          } finally {
              for (BatchExecutor batchExecutor : batchExecutors) {
                  if (batchExecutor != null) {
                      batchExecutor.close();
                  }
              }
          }
      }
  
      /**
       * 批量同步
       *
       * @param mappingConfig 配置集合
       * @param dmls 批量 DML
       */
      public void sync(Map<String, Map<String, MappingConfig>> mappingConfig, List<Dml> dmls, Properties envProperties) {
          sync(dmls, dml -> {
              if (dml.getIsDdl() != null && dml.getIsDdl() && StringUtils.isNotEmpty(dml.getSql())) {
                  // DDL
              columnsTypeCache.remove(dml.getDestination() + "." + dml.getDatabase() + "." + dml.getTable());
              return false;
          } else {
              // DML
              String destination = StringUtils.trimToEmpty(dml.getDestination());
              String groupId = StringUtils.trimToEmpty(dml.getGroupId());
              String database = dml.getDatabase();
              String table = dml.getTable();
              Map<String, MappingConfig> configMap;
              if (envProperties != null && !"tcp".equalsIgnoreCase(envProperties.getProperty("canal.conf.mode"))) {
                  configMap = mappingConfig.get(destination + "-" + groupId + "_" + database + "-" + table);
              } else {
                  configMap = mappingConfig.get(destination + "_" + database + "-" + table);
              }
  
              if (configMap == null) {
                  return false;
              }
  
              if (configMap.values().isEmpty()) {
                  return false;
              }
  
              for (MappingConfig config : configMap.values()) {
                  appendDmlPartition(config, dml);
              }
              return true;
          }
      }   );
      }
  
      /**
       * 将Dml加入 {@link #dmlsPartition}
       *
       * @param config 表映射配置
       * @param dml    Dml对象
       */
      public void appendDmlPartition(MappingConfig config, Dml dml) {
          boolean caseInsensitive = config.getDbMapping().isCaseInsensitive();
          if (config.getConcurrent()) {
              List<SingleDml> singleDmls = SingleDml.dml2SingleDmls(dml, caseInsensitive);
              singleDmls.forEach(singleDml -> {
                  int hash = pkHash(config.getDbMapping(), singleDml.getData());
                  SyncItem syncItem = new SyncItem(config, singleDml);
                  dmlsPartition[hash].add(syncItem);
              });
          } else {
              int hash = 0;
              List<SingleDml> singleDmls = SingleDml.dml2SingleDmls(dml, caseInsensitive);
              singleDmls.forEach(singleDml -> {
                  SyncItem syncItem = new SyncItem(config, singleDml);
                  dmlsPartition[hash].add(syncItem);
              });
          }
      }
  
      /**
       * 单条 dml 同步
       *
       * @param batchExecutor 批量事务执行器
       * @param config 对应配置对象
       * @param dml DML
       */
      public void sync(BatchExecutor batchExecutor, MappingConfig config, SingleDml dml) {
          if (config != null) {
              try {
                  String type = dml.getType();
                  if (type != null && type.equalsIgnoreCase("INSERT")) {
                      insert(batchExecutor, config, dml);
                  } else if (type != null && type.equalsIgnoreCase("UPDATE")) {
                      update(batchExecutor, config, dml);
                  } else if (type != null && type.equalsIgnoreCase("DELETE")) {
                      delete(batchExecutor, config, dml);
                  } else if (type != null && type.equalsIgnoreCase("TRUNCATE")) {
                      truncate(batchExecutor, config);
                  }
                  if (logger.isDebugEnabled()) {
                      logger.debug("DML: {}", JSON.toJSONString(dml, Feature.WriteNulls));
                  }
              } catch (SQLException e) {
                  throw new RuntimeException(e);
              }
          }
      }
  
      /**
       * 插入操作
       *
       * @param config 配置项
       * @param dml DML数据
       */
      private void insert(BatchExecutor batchExecutor, MappingConfig config, SingleDml dml) throws SQLException {
          Map<String, Object> data = dml.getData();
          if (data == null || data.isEmpty()) {
              return;
          }
  
          DbMapping dbMapping = config.getDbMapping();
          String backtick = SyncUtil.getBacktickByDbType(dataSource.getDbType());
          Map<String, String> columnsMap = SyncUtil.getColumnsMap(dbMapping, data);
  
          StringBuilder insertSql = new StringBuilder();
          insertSql.append("INSERT INTO ").append(SyncUtil.getDbTableName(dbMapping, dataSource.getDbType())).append(" (");
  
          columnsMap.forEach((targetColumnName, srcColumnName) -> insertSql.append(backtick)
              .append(targetColumnName)
              .append(backtick)
              .append(","));
          int len = insertSql.length();
          insertSql.delete(len - 1, len).append(") VALUES (");
          int mapLen = columnsMap.size();
          for (int i = 0; i < mapLen; i++) {
              insertSql.append("?,");
          }
          len = insertSql.length();
          insertSql.delete(len - 1, len).append(")");
  
          Map<String, Integer> ctype = getTargetColumnType(batchExecutor.getConn(), config);
  
          List<Map<String, ?>> values = new ArrayList<>();
          for (Map.Entry<String, String> entry : columnsMap.entrySet()) {
              String targetColumnName = entry.getKey();
              String srcColumnName = entry.getValue();
              if (srcColumnName == null) {
                  srcColumnName = Util.cleanColumn(targetColumnName);
              }
  
              Integer type = ctype.get(Util.cleanColumn(targetColumnName).toLowerCase());
              if (type == null) {
                  throw new RuntimeException("Target column: " + targetColumnName + " not matched");
              }
              Object value = data.get(srcColumnName);
              BatchExecutor.setValue(values, type, value);
          }
  
          try {
              batchExecutor.execute(insertSql.toString(), values);
          } catch (SQLException e) {
              if (skipDupException
                  && (e.getMessage().contains("Duplicate entry") || e.getMessage().contains("duplicate key") || e.getMessage().startsWith("ORA-00001:"))) {
                  // ignore
                  // TODO 增加更多关系数据库的主键冲突的错误码
              } else {
                  throw e;
              }
          }
          if (logger.isTraceEnabled()) {
              logger.trace("Insert into target table, sql: {}", insertSql);
          }
  
      }
  
      /**
       * 更新操作
       *
       * @param config 配置项
       * @param dml DML数据
       */
      private void update(BatchExecutor batchExecutor, MappingConfig config, SingleDml dml) throws SQLException {
          Map<String, Object> data = dml.getData();
          if (data == null || data.isEmpty()) {
              return;
          }
  
          Map<String, Object> old = dml.getOld();
          if (old == null || old.isEmpty()) {
              return;
          }
  
          DbMapping dbMapping = config.getDbMapping();
          String backtick = SyncUtil.getBacktickByDbType(dataSource.getDbType());
          Map<String, String> columnsMap = SyncUtil.getColumnsMap(dbMapping, data);
  
          Map<String, Integer> ctype = getTargetColumnType(batchExecutor.getConn(), config);
  
          StringBuilder updateSql = new StringBuilder();
          updateSql.append("UPDATE ").append(SyncUtil.getDbTableName(dbMapping, dataSource.getDbType())).append(" SET ");
          List<Map<String, ?>> values = new ArrayList<>();
          boolean hasMatched = false;
          for (String srcColumnName : old.keySet()) {
              List<String> targetColumnNames = new ArrayList<>();
              columnsMap.forEach((targetColumn, srcColumn) -> {
                  if (srcColumnName.equalsIgnoreCase(srcColumn)) {
                      targetColumnNames.add(targetColumn);
                  }
              });
              if (!targetColumnNames.isEmpty()) {
                  hasMatched = true;
                  for (String targetColumnName : targetColumnNames) {
                      updateSql.append(backtick).append(targetColumnName).append(backtick).append("=?, ");
                      Integer type = ctype.get(Util.cleanColumn(targetColumnName).toLowerCase());
                      if (type == null) {
                          throw new RuntimeException("Target column: " + targetColumnName + " not matched");
                      }
                      BatchExecutor.setValue(values, type, data.get(srcColumnName));
                  }
              }
          }
          if (!hasMatched) {
              logger.warn("Did not matched any columns to update ");
              return;
          }
          int len = updateSql.length();
          updateSql.delete(len - 2, len).append(" WHERE ");
  
          // 拼接主键
          appendCondition(dbMapping, updateSql, ctype, values, data, old);
          batchExecutor.execute(updateSql.toString(), values);
          if (logger.isTraceEnabled()) {
              logger.trace("Update target table, sql: {}", updateSql);
          }
      }
  
      /**
       * 删除操作
       *
       * @param config
       * @param dml
       */
      private void delete(BatchExecutor batchExecutor, MappingConfig config, SingleDml dml) throws SQLException {
          Map<String, Object> data = dml.getData();
          if (data == null || data.isEmpty()) {
              return;
          }
  
          DbMapping dbMapping = config.getDbMapping();
          Map<String, Integer> ctype = getTargetColumnType(batchExecutor.getConn(), config);
  
          StringBuilder sql = new StringBuilder();
          sql.append("DELETE FROM ").append(SyncUtil.getDbTableName(dbMapping, dataSource.getDbType())).append(" WHERE ");
  
          List<Map<String, ?>> values = new ArrayList<>();
          // 拼接主键
          appendCondition(dbMapping, sql, ctype, values, data);
          batchExecutor.execute(sql.toString(), values);
          if (logger.isTraceEnabled()) {
              logger.trace("Delete from target table, sql: {}", sql);
          }
      }
  
      /**
       * truncate操作
       *
       * @param config
       */
      private void truncate(BatchExecutor batchExecutor, MappingConfig config) throws SQLException {
          DbMapping dbMapping = config.getDbMapping();
          StringBuilder sql = new StringBuilder();
          sql.append("TRUNCATE TABLE ").append(SyncUtil.getDbTableName(dbMapping, dataSource.getDbType()));
          batchExecutor.execute(sql.toString(), new ArrayList<>());
          if (logger.isTraceEnabled()) {
              logger.trace("Truncate target table, sql: {}", sql);
          }
      }
  
      /**
       * 获取目标字段类型
       *
       * @param conn sql connection
       * @param config 映射配置
       * @return 字段sqlType
       */
      private Map<String, Integer> getTargetColumnType(Connection conn, MappingConfig config) {
          DbMapping dbMapping = config.getDbMapping();
          String cacheKey = config.getDestination() + "." + dbMapping.getDatabase() + "." + dbMapping.getTable();
          Map<String, Integer> columnType = columnsTypeCache.get(cacheKey);
          if (columnType == null) {
              synchronized (RdbSyncService.class) {
                  columnType = columnsTypeCache.get(cacheKey);
                  if (columnType == null) {
                      columnType = new LinkedHashMap<>();
                      final Map<String, Integer> columnTypeTmp = columnType;
                      String sql = "SELECT * FROM " + SyncUtil.getDbTableName(dbMapping, dataSource.getDbType()) + " WHERE 1=2";
                      Util.sqlRS(conn, sql, rs -> {
                          try {
                              ResultSetMetaData rsd = rs.getMetaData();
                              int columnCount = rsd.getColumnCount();
                              for (int i = 1; i <= columnCount; i++) {
                                  int colType = rsd.getColumnType(i);
                                  // 修复year类型作为date处理时的data truncated问题
                                  if ("YEAR".equals(rsd.getColumnTypeName(i))) {
                                      colType = Types.VARCHAR;
                                  }
                                  columnTypeTmp.put(rsd.getColumnName(i).toLowerCase(), colType);
                              }
                              columnsTypeCache.put(cacheKey, columnTypeTmp);
                          } catch (SQLException e) {
                              logger.error(e.getMessage(), e);
                          }
                      });
                  }
              }
          }
          return columnType;
      }
  
      /**
       * 拼接主键 where条件
       */
      private void appendCondition(MappingConfig.DbMapping dbMapping, StringBuilder sql, Map<String, Integer> ctype,
                                   List<Map<String, ?>> values, Map<String, Object> d) {
          appendCondition(dbMapping, sql, ctype, values, d, null);
      }
  
      private void appendCondition(MappingConfig.DbMapping dbMapping, StringBuilder sql, Map<String, Integer> ctype,
                                   List<Map<String, ?>> values, Map<String, Object> d, Map<String, Object> o) {
          String backtick = SyncUtil.getBacktickByDbType(dataSource.getDbType());
  
          // 拼接主键
          for (Map.Entry<String, String> entry : dbMapping.getTargetPk().entrySet()) {
              String targetColumnName = entry.getKey();
              String srcColumnName = entry.getValue();
              if (srcColumnName == null) {
                  srcColumnName = Util.cleanColumn(targetColumnName);
              }
              sql.append(backtick).append(targetColumnName).append(backtick).append("=? AND ");
              Integer type = ctype.get(Util.cleanColumn(targetColumnName).toLowerCase());
              if (type == null) {
                  throw new RuntimeException("Target column: " + targetColumnName + " not matched");
              }
              // 如果有修改主键的情况
              if (o != null && o.containsKey(srcColumnName)) {
                  BatchExecutor.setValue(values, type, o.get(srcColumnName));
              } else {
                  BatchExecutor.setValue(values, type, d.get(srcColumnName));
              }
          }
          int len = sql.length();
          sql.delete(len - 4, len);
      }
  
      public static class SyncItem {
  
          private MappingConfig config;
          private SingleDml     singleDml;
  
          public SyncItem(MappingConfig config, SingleDml singleDml){
              this.config = config;
              this.singleDml = singleDml;
          }
      }
  
      /**
       * 取主键hash
       */
      public int pkHash(DbMapping dbMapping, Map<String, Object> d) {
          return pkHash(dbMapping, d, null);
      }
  
      public int pkHash(DbMapping dbMapping, Map<String, Object> d, Map<String, Object> o) {
          int hash = 0;
          // 取主键
          for (Map.Entry<String, String> entry : dbMapping.getTargetPk().entrySet()) {
              String targetColumnName = entry.getKey();
              String srcColumnName = entry.getValue();
              if (srcColumnName == null) {
                  srcColumnName = Util.cleanColumn(targetColumnName);
              }
              Object value = null;
              if (o != null && o.containsKey(srcColumnName)) {
                  value = o.get(srcColumnName);
              } else if (d != null) {
                  value = d.get(srcColumnName);
              }
              if (value != null) {
                  hash += value.hashCode();
              }
          }
          hash = Math.abs(hash) % threads;
          return Math.abs(hash);
      }
  
      public void close() {
          for (int i = 0; i < threads; i++) {
              executorThreads[i].shutdown();
          }
      }
  }
  