storm-sql-kafka问题情况
首先上官方文档：http://storm.apache.org/releases/1.2.2/storm-sql.html
解决的问题
1、kafka版本不对
开始测试时采用storm1.2.2+kafka2.0.1的组合进行测试，测试过程完全按照官方文档所写进行。出现了kafka无法获取scala依赖的问题，经查找发现是storm-kafka采用的是2.10版本的scala，而kafka2.0.1采用的是2.11或者2.12，无法兼容。于是只能换回kafka0.8.2.2进行测试。
2、storm找不到依赖
按照官方文档所写的提交命令无法找到storm-sql-runtime，所以需要加入storm-sql相关依赖包，任务提交命令如下：
./bin/storm sql /softwares/storm-1.2.2/storm-sql.sql stormsql1 --artifacts "org.apache.storm:storm-sql-kafka:1.2.2,org.apache.storm:storm-kafka:1.2.2,org.apache.kafka:kafka_2.10:0.8.2.2^org.slf4j:slf4j-log4j12,org.apache.kafka:kafka-clients:0.8.2.2,org.apache.storm:storm-sql-runtime:1.2.2,org.apache.storm:storm-sql-core:1.2.2"
遇到的问题
任务提交成功，但是bolt执行总是失败。
此问题无法直接解决，并且在UI上无法找到日志。
排除过程如下：首先去日志里看看：
less logs/workers-artifacts/stormsql1-31-1542269873/6700/worker.log
发现：
2018-11-15 16:18:03.992 o.a.s.t.t.s.TransactionalState Thread-4-$spoutcoord-spout-TRIDENTSTREAMSCANREL_21_0-executor[2 2] [WARN] Failed to deserialize zookeeper data for path /meta/1 org.apache.storm.shade.org.json.simple.parser.ParseException: null at org.apache.storm.shade.org.json.simple.parser.Yylex.yylex(Unknown Source) ~[storm-core-1.2.2.jar:1.2.2] at org.apache.storm.shade.org.json.simple.parser.JSONParser.nextToken(Unknown Source) ~[storm-core-1.2.2.jar:1.2.2] at org.apache.storm.shade.org.json.simple.parser.JSONParser.parse(Unknown Source) ~[storm-core-1.2.2.jar:1.2.2] at org.apache.storm.shade.org.json.simple.parser.JSONParser.parse(Unknown Source) ~[storm-core-1.2.2.jar:1.2.2] at org.apache.storm.shade.org.json.simple.parser.JSONParser.parse(Unknown Source) ~[storm-core-1.2.2.jar:1.2.2] at org.apache.storm.shade.org.json.simple.JSONValue.parseWithException(Unknown Source) ~[storm-core-1.2.2.jar:1.2.2] at org.apache.storm.trident.topology.state.TransactionalState.getData(TransactionalState.java:176) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.trident.topology.state.RotatingTransactionalState.sync(RotatingTransactionalState.java:165) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.trident.topology.state.RotatingTransactionalState.<init>(RotatingTransactionalState.java:46) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.trident.spout.TridentSpoutCoordinator.prepare(TridentSpoutCoordinator.java:57) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.topology.BasicBoltExecutor.prepare(BasicBoltExecutor.java:43) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.daemon.executor$fn__10795$fn__10808.invoke(executor.clj:803) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.util$async_loop$fn__553.invoke(util.clj:482) [storm-core-1.2.2.jar:1.2.2] at clojure.lang.AFn.run(AFn.java:22) [clojure-1.7.0.jar:?] at java.lang.Thread.run(Thread.java:748) [?:1.8.0_131] 2018-11-15 16:18:03.997 o.a.s.d.executor Thread-4-$spoutcoord-spout-TRIDENTSTREAMSCANREL_21_0-executor[2 2] [INFO] Prepared bolt $spoutcoord-spout-TRIDENTSTREAMSCANREL_21_0:(2) 2018-11-15 16:18:04.550 o.a.s.k.t.TridentKafkaState Thread-14-b-0-executor[4 4] [WARN] Could not send messages [[null, null], [null, null], [null, null]] to topic = testout java.lang.NullPointerException: null at org.apache.storm.kafka.IntSerializer.serialize(IntSerializer.java:35) ~[dep-org.apache.storm-storm-kafka-jar-1.2.2.jar.1542245912000:1.2.2] at org.apache.storm.kafka.IntSerializer.serialize(IntSerializer.java:26) ~[dep-org.apache.storm-storm-kafka-jar-1.2.2.jar.1542245912000:1.2.2] at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:318) ~[dep-org.apache.kafka-kafka-clients-jar-0.8.2.2.jar.1542267398000:?] at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:248) ~[dep-org.apache.kafka-kafka-clients-jar-0.8.2.2.jar.1542267398000:?] at org.apache.storm.kafka.trident.TridentKafkaState.updateState(TridentKafkaState.java:87) [dep-org.apache.storm-storm-kafka-jar-1.2.2.jar.1542245912000:1.2.2] at org.apache.storm.kafka.trident.TridentKafkaUpdater.updateState(TridentKafkaUpdater.java:29) [dep-org.apache.storm-storm-kafka-jar-1.2.2.jar.1542245912000:1.2.2] at org.apache.storm.kafka.trident.TridentKafkaUpdater.updateState(TridentKafkaUpdater.java:26) [dep-org.apache.storm-storm-kafka-jar-1.2.2.jar.1542245912000:1.2.2] at org.apache.storm.trident.planner.processor.PartitionPersistProcessor.finishBatch(PartitionPersistProcessor.java:98) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.trident.planner.SubtopologyBolt.finishBatch(SubtopologyBolt.java:151) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.trident.topology.TridentBoltExecutor.finishBatch(TridentBoltExecutor.java:266) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.trident.topology.TridentBoltExecutor.checkFinish(TridentBoltExecutor.java:299) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.trident.topology.TridentBoltExecutor.execute(TridentBoltExecutor.java:373) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.daemon.executor$fn__10795$tuple_action_fn__10797.invoke(executor.clj:739) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.daemon.executor$mk_task_receiver$fn__10716.invoke(executor.clj:468) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.disruptor$clojure_handler$reify__10135.onEvent(disruptor.clj:41) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.utils.DisruptorQueue.consumeBatchToCursor(DisruptorQueue.java:509) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.utils.DisruptorQueue.consumeBatchWhenAvailable(DisruptorQueue.java:487) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.disruptor$consume_batch_when_available.invoke(disruptor.clj:74) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.daemon.executor$fn__10795$fn__10808$fn__10861.invoke(executor.clj:861) [storm-core-1.2.2.jar:1.2.2] at org.apache.storm.util$async_loop$fn__553.invoke(util.clj:484) [storm-core-1.2.2.jar:1.2.2] at clojure.lang.AFn.run(AFn.java:22) [clojure-1.7.0.jar:?] at java.lang.Thread.run(Thread.java:748) [?:1.8.0_131]
接下来分为两步，其一是查找/meta/1这个目录在zookeeper的哪里，另一个是查找报错的源码在哪里，根据storm源码可以看到：
public Object getData(String path) { path = "/" + path; try { Object data; if (_curator.checkExists().forPath(path) != null) { // Use parseWithException instead of parse so we can capture deserialization errors in the log. // They are likely to be bugs in the spout code. try { data = JSONValue.parseWithException(new String(_curator.getData().forPath(path), "UTF-8")); } catch (ParseException e) { LOG.warn("Failed to deserialize zookeeper data for path {}", path, e); data = null; } } else { data = null; } LOG.debug("Get. [path = {}] => [data = {}]", path, data); return data; } catch (Exception e) { throw new RuntimeException(e); } }
可以看到报错的是JSONValue.parseWithException出错。获取数据是解析一个json，并放到data里，而通过判断条件我们可以知道path是有内容的，只不过读不出来。
通过查询源码找到/meta/1的完整路径为：/transactional/....../meta/1，去此路径下找到对应的文件为：/transactional/TRIDENTSTREAMSCANREL_21_0/coordinator/meta/1
获取此文件信息：get /transactional/TRIDENTSTREAMSCANREL_21_0/coordinator/meta/1
[GlobalPartitionInformation{topic=testin, partitionMap={0=cloud22:19092, 1=cloud22:19092, 2=cloud22:19092, 3=cloud22:19092, 4=cloud22:19092}}]
cZxid = 0xf02f
ctime = Thu Nov 15 10:08:13 CST 2018
mZxid = 0x45a9b
mtime = Thu Nov 15 17:02:31 CST 2018
pZxid = 0xf02f
cversion = 0
dataVersion = 11444
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 142
numChildren = 0
可以发现，emmm...这一段信息看格式应该是通过toString写出来的，但是读却是用json格式读。代码鬼才，我觉得不行。
结论：storm-sql-kafka基本不可用，至少未找到解决方案，从错误来看，zookeeper中写kafka partitions meta的代码和读的代码完全无法匹配上。在不修改源码的前提下无法解决此问题。
