feature(canal):support start with timestamp position(empty journal_file,set position=0),#2594

README.md

@@ -84,6 +84,7 @@ canal 特别设计了 client-server 模式，交互协议使用 protobuf 3.0 , c
 - canal go客户端: [https://github.com/CanalClient/canal-go](https://github.com/CanalClient/canal-go)
 - canal php客户端: [https://github.com/xingwenge/canal-php](https://github.com/xingwenge/canal-php)
 - canal Python客户端：[https://github.com/haozi3156666/canal-python](https://github.com/haozi3156666/canal-python)
+- canal Rust客户端：[https://github.com/laohanlinux/canal-rs](https://github.com/laohanlinux/canal-rs)
 
 canal 作为 MySQL binlog 增量获取和解析工具，可将变更记录投递到 MQ 系统中，比如 Kafka/RocketMQ，可以借助于 MQ 的多语言能力 
 

client-adapter/launcher/src/main/java/com/alibaba/otter/canal/adapter/launcher/loader/AbstractCanalAdapterWorker.java

@@ -174,11 +174,6 @@ public abstract class AbstractCanalAdapterWorker {
             if (i == retry - 1) {
                 connector.ack();
                 logger.error(e.getMessage() + " Error sync but ACK!");
-                try {
-                    Thread.sleep(500);
-                } catch (InterruptedException e1) {
-                    // ignore
-                }
                 return true;
             } else {
                 connector.rollback();

client/src/main/java/com/alibaba/otter/canal/client/kafka/KafkaCanalConnector.java

@@ -61,11 +61,11 @@ public class KafkaCanalConnector implements CanalMQConnector {
             batchSize = 100;
         }
         properties.put("max.poll.records", batchSize.toString());
-        properties.put("key.deserializer", StringDeserializer.class);
+        properties.put("key.deserializer", StringDeserializer.class.getName());
         if (!flatMessage) {
-            properties.put("value.deserializer", MessageDeserializer.class);
+            properties.put("value.deserializer", MessageDeserializer.class.getName());
         } else {
-            properties.put("value.deserializer", StringDeserializer.class);
+            properties.put("value.deserializer", StringDeserializer.class.getName());
         }
     }
 
@@ -183,13 +183,14 @@ public class KafkaCanalConnector implements CanalMQConnector {
 
         ConsumerRecords<String, Message> records = kafkaConsumer.poll(unit.toMillis(timeout));
 
-        if (!records.isEmpty()) {
         currentOffsets.clear();
+        for (TopicPartition topicPartition : records.partitions()) {
+            currentOffsets.put(topicPartition.partition(), kafkaConsumer.position(topicPartition));
+        }
+
+        if (!records.isEmpty()) {
             List<Message> messages = new ArrayList<>();
             for (ConsumerRecord<String, Message> record : records) {
-                if (currentOffsets.get(record.partition()) == null) {
-                    currentOffsets.put(record.partition(), record.offset());
-                }
                 messages.add(record.value());
             }
             return messages;
@@ -220,13 +221,14 @@ public class KafkaCanalConnector implements CanalMQConnector {
 
         ConsumerRecords<String, String> records = kafkaConsumer2.poll(unit.toMillis(timeout));
 
-        if (!records.isEmpty()) {
         currentOffsets.clear();
+        for (TopicPartition topicPartition : records.partitions()) {
+            currentOffsets.put(topicPartition.partition(), kafkaConsumer2.position(topicPartition));
+        }
+
+        if (!records.isEmpty()) {
             List<FlatMessage> flatMessages = new ArrayList<>();
             for (ConsumerRecord<String, String> record : records) {
-                if (currentOffsets.get(record.partition()) == null) {
-                    currentOffsets.put(record.partition(), record.offset());
-                }
                 String flatMessageJson = record.value();
                 FlatMessage flatMessage = JSON.parseObject(flatMessageJson, FlatMessage.class);
                 flatMessages.add(flatMessage);
@@ -246,14 +248,12 @@ public class KafkaCanalConnector implements CanalMQConnector {
         // 回滚所有分区
         if (kafkaConsumer != null) {
             for (Map.Entry<Integer, Long> entry : currentOffsets.entrySet()) {
-                kafkaConsumer.seek(new TopicPartition(topic, entry.getKey()), currentOffsets.get(entry.getKey()));
+                kafkaConsumer.seek(new TopicPartition(topic, entry.getKey()), entry.getValue() - 1);
-                kafkaConsumer.commitSync();
             }
         }
         if (kafkaConsumer2 != null) {
             for (Map.Entry<Integer, Long> entry : currentOffsets.entrySet()) {
-                kafkaConsumer2.seek(new TopicPartition(topic, entry.getKey()), currentOffsets.get(entry.getKey()));
+                kafkaConsumer2.seek(new TopicPartition(topic, entry.getKey()), entry.getValue() - 1);
-                kafkaConsumer.commitSync();
             }
         }
     }

parse/src/main/java/com/alibaba/otter/canal/parse/inbound/mysql/MysqlEventParser.java

@@ -493,12 +493,7 @@ public class MysqlEventParser extends AbstractMysqlEventParser implements CanalE
                                     && logPosition.getPostion().getServerId() != null
                                     && !logPosition.getPostion().getServerId().equals(findServerId(mysqlConnection));
                     if (case2) {
-                        long timestamp = logPosition.getPostion().getTimestamp();
+                        EntryPosition findPosition = fallbackFindByStartTimestamp(logPosition, mysqlConnection);
-                        long newStartTimestamp = timestamp - fallbackIntervalInSeconds * 1000;
-                        logger.warn("prepare to find start position by last position {}:{}:{}", new Object[] { "", "",
-                                logPosition.getPostion().getTimestamp() });
-                        EntryPosition findPosition = findByStartTimeStamp(mysqlConnection, newStartTimestamp);
-                        // 重新置为一下
                         dumpErrorCount = 0;
                         return findPosition;
                     }
@@ -508,6 +503,10 @@ public class MysqlEventParser extends AbstractMysqlEventParser implements CanalE
                         // 如果binlog位点不存在，并且属于timestamp不为空,可以返回null走到oss binlog处理
                         return null;
                     }
+                } else if (StringUtils.isBlank(logPosition.getPostion().getJournalName())
+                        && logPosition.getPostion().getPosition() <= 0
+                        && logPosition.getPostion().getTimestamp() > 0) {
+                    return fallbackFindByStartTimestamp(logPosition,mysqlConnection);
                 }
                 // 其余情况
                 logger.warn("prepare to find start position just last position\n {}",
@@ -523,6 +522,21 @@ public class MysqlEventParser extends AbstractMysqlEventParser implements CanalE
         }
     }
 
+    /**
+     * find position by timestamp with a fallback interval seconds.
+     *
+     * @param logPosition
+     * @param mysqlConnection
+     * @return
+     */
+    protected EntryPosition fallbackFindByStartTimestamp(LogPosition logPosition,MysqlConnection mysqlConnection){
+        long timestamp = logPosition.getPostion().getTimestamp();
+        long newStartTimestamp = timestamp - fallbackIntervalInSeconds * 1000;
+        logger.warn("prepare to find start position by last position {}:{}:{}", new Object[] { "", "",
+                logPosition.getPostion().getTimestamp() });
+        return findByStartTimeStamp(mysqlConnection, newStartTimestamp);
+    }
+
     // 根据想要的position，可能这个position对应的记录为rowdata，需要找到事务头，避免丢数据
     // 主要考虑一个事务执行时间可能会几秒种，如果仅仅按照timestamp相同，则可能会丢失事务的前半部分数据
     private Long findTransactionBeginPosition(ErosaConnection mysqlConnection, final EntryPosition entryPosition)