TransactionEnd transactionEnd = createTransactionEnd(0L); // MyISAM可能不会有xid事件
Header header = createHeader(binlogFileName, event.getHeader(), "", "", null);
return createEntry(header, EntryType.TRANSACTIONEND, transactionEnd.toByteString());
} else {
// DDL语句处理
DdlResult result = SimpleDdlParser.parse(queryString, event.getDbName());
String schemaName = event.getDbName();
if (StringUtils.isNotEmpty(result.getSchemaName())) {
schemaName = result.getSchemaName();
}
String tableName = result.getTableName();
EventType type = EventType.QUERY;
// fixed issue https://github.com/alibaba/canal/issues/58
if (result.getType() == EventType.ALTER || result.getType() == EventType.ERASE
|| result.getType() == EventType.CREATE || result.getType() == EventType.TRUNCATE
|| result.getType() == EventType.RENAME) { //针对DDL类型
type = result.getType();
if (StringUtils.isEmpty(tableName)
|| (result.getType() == EventType.RENAME && StringUtils.isEmpty(result.getOriTableName()))) {
//如果解析不出tableName,记录一下日志，方便bugfix，目前直接抛出异常，中断解析
throw new CanalParseException(
"SimpleDdlParser process query failed. pls submit issue with this queryString: "
+ queryString + " , and DdlResult: " + result.toString());
// return null;
} else {
// check name filter
if (nameFilter != null && !nameFilter.filter(schemaName + "." + tableName)) {
if (result.getType() == EventType.RENAME) {
// rename校验只要源和目标满足一个就进行操作
if (nameFilter != null
&& !nameFilter.filter(result.getOriSchemaName() + "." + result.getOriTableName())) {
return null;
}
} else {
// 其他情况返回null
return null;
}
}
}
} else if (result.getType() == EventType.INSERT || result.getType() == EventType.UPDATE
|| result.getType() == EventType.DELETE) {
// 对外返回，保证兼容，还是返回QUERY类型，这里暂不解析tableName，所以无法支持过滤
if (filterQueryDml) {
return null;
}
} else if (filterQueryDcl) {
return null;
}
// 更新下table meta cache
if (tableMetaCache != null
&& (result.getType() == EventType.ALTER || result.getType() == EventType.ERASE || result.getType() == EventType.RENAME)) {
if (StringUtils.isNotEmpty(tableName)) {
// 如果解析到了正确的表信息，则根据全名进行清除
tableMetaCache.clearTableMetaWithFullName(schemaName + "." + tableName);
} else {
// 如果无法解析正确的表信息，则根据schema进行清除
tableMetaCache.clearTableMetaWithSchemaName(schemaName);
}
}
Header header = createHeader(binlogFileName, event.getHeader(), schemaName, tableName, type);
RowChange.Builder rowChangeBuider = RowChange.newBuilder();
if (result.getType() != EventType.QUERY) {
rowChangeBuider.setIsDdl(true);
}
rowChangeBuider.setSql(queryString);
if (StringUtils.isNotEmpty(event.getDbName())) {//可能为空
rowChangeBuider.setDdlSchemaName(event.getDbName());
}
rowChangeBuider.setEventType(result.getType());
return createEntry(header, EntryType.ROWDATA, rowChangeBuider.build().toByteString());
}
}