汇总：加载连接器后未创建主题

Question

我尝试连接到几个数据库，包括MySQL和MSSQL，我没有问题。

但是，当我试图连接到某个远程MySQL数据库（只能从我公司的网络访问），其中包含一个有近300万条记录的视图时，连接器已加载，状态表示它正在运行但没有任何创建主题以使用它的数据。

可能是什么原因？我在哪里可以找到正确的日志文件，知道发生了什么？

以下是连接器的示例：

{
  "name": "mysql-source",
   "config": {
   "connector.class": "io.confluent.connect.jdbc.JdbcSourceConnector",
   "key.converter": "io.confluent.connect.avro.AvroConverter",
   "key.converter.schema.registry.url": "http://localhost:8081",
   "value.converter": "io.confluent.connect.avro.AvroConverter",
   "value.converter.schema.registry.url": "http://localhost:8081",
   "incrementing.column.name": "Id",
   "tasks.max": "1",
   "table.types": "VIEW",
   "table.whitelist": "ticket_rep",
   "mode": "incrementing",
   "topic.prefix": "mysql-",
   "name": "mysql-source",
   "validate.non.null": "false",
   "connection.url": "jdbc:mysql://XX.XXX.XX.XX:3306/database? 
    user=user&password=password"
 }

}

这些是我运行汇合日志连接时的日志结果：

> [2018-09-11 16:37:57,382] ERROR Failed to run query for table TimestampIncrementingTableQuerier{name='foo', query='null', topicPrefix='mysql-', timestampColumn='null', incrementingColumn='id'}: {} (io.confluent.connect.jdbc.source.JdbcSourceTask:247)
java.sql.SQLException: Java heap space
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:129)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97)
    at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122)
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeInternal(ClientPreparedStatement.java:975)
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeQuery(ClientPreparedStatement.java:1025)
    at io.confluent.connect.jdbc.source.TimestampIncrementingTableQuerier.executeQuery(TimestampIncrementingTableQuerier.java:201)
    at io.confluent.connect.jdbc.source.TableQuerier.maybeStartQuery(TableQuerier.java:84)
    at io.confluent.connect.jdbc.source.TimestampIncrementingTableQuerier.maybeStartQuery(TimestampIncrementingTableQuerier.java:55)
    at io.confluent.connect.jdbc.source.JdbcSourceTask.poll(JdbcSourceTask.java:225)
    at org.apache.kafka.connect.runtime.WorkerSourceTask.execute(WorkerSourceTask.java:179)
    at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:170)
    at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:214)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at java.lang.Thread.run(Thread.java:748)
[2018-09-11 16:38:02,523] ERROR Failed to run query for table TimestampIncrementingTableQuerier{name='foo', query='null', topicPrefix='mysql-', timestampColumn='null', incrementingColumn='id'}: {} (io.confluent.connect.jdbc.source.JdbcSourceTask:247)
com.mysql.cj.jdbc.exceptions.PacketTooBigException: Packet for query is too large (7,562,612 > 4,194,304). You can change this value on the server by setting the 'max_allowed_packet' variable.
    at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:107)
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeInternal(ClientPreparedStatement.java:975)
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeQuery(ClientPreparedStatement.java:1025)
    at io.confluent.connect.jdbc.source.TimestampIncrementingTableQuerier.executeQuery(TimestampIncrementingTableQuerier.java:201)
    at io.confluent.connect.jdbc.source.TableQuerier.maybeStartQuery(TableQuerier.java:84)
    at io.confluent.connect.jdbc.source.TimestampIncrementingTableQuerier.maybeStartQuery(TimestampIncrementingTableQuerier.java:55)
    at io.confluent.connect.jdbc.source.JdbcSourceTask.poll(JdbcSourceTask.java:225)
    at org.apache.kafka.connect.runtime.WorkerSourceTask.execute(WorkerSourceTask.java:179)
    at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:170)
    at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:214)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at java.lang.Thread.run(Thread.java:748)

Answer 1

com.mysql.cj.jdbc.exceptions.PacketTooBigException: Packet for query is too large是MySQL方面的一个问题，可以通过增加max_allowed_packet变量的值来修复。为此，您需要包含

max_allowed_packet=512M

在my.cnf（或my.ini，取决于你运行的操作系统）文件（在[mysqld]部分）然后重启MySQL。重启MySQL后，

SHOW VARIABLES LIKE 'max_allowed_packet';

应该返回你在MySQL配置文件中设置的值。有关此错误的更多详细信息，请参阅MySQL documentation。 java.sql.SQLException: Java heap space表示Kafka连接的堆空间不足。可以通过运行来控制起始和最大堆大小

KAFKA_HEAP_OPTS="-Xms512m -Xmx1g" connect-standalone connect-worker.properties mysql-source-connector.properties

将起始堆大小设置为512 MB，最大大小为1 GB。您可能需要根据需要更改尺寸。