Storm0.9.3启动后关于参数问题的报错

启动storm后，如果发现报错如下，或者有类似的错误提示：

Exception in thread "main" expected '<document start>', but found BlockMappingStart in 'reader', line 43, column 1:

说明参数有错误，在配置文件的43行第1列。

原因是因为storm 0.9.3（其他版本或许相同，未做考证）版本中的配置文件，必须以空格开头，即所有配置文件的开头需要是空格。

storm@h1:/opt$ Exception in thread "main" expected '<document start>', but found BlockMappingStart in 'reader', line 43, column 1:    supervisor.slots.ports:    at org.yaml.snakeyaml.parser.ParserImpl$ParseDocumentStart.produce(ParserImpl.java:225)    at org.yaml.snakeyaml.parser.ParserImpl.peekEvent(ParserImpl.java:158)    at org.yaml.snakeyaml.parser.ParserImpl.checkEvent(ParserImpl.java:143)    at org.yaml.snakeyaml.composer.Composer.getSingleNode(Composer.java:108)    at org.yaml.snakeyaml.constructor.BaseConstructor.getSingleData(BaseConstructor.java:120)    at org.yaml.snakeyaml.Yaml.loadFromReader(Yaml.java:481)    at org.yaml.snakeyaml.Yaml.load(Yaml.java:424)    at backtype.storm.utils.Utils.findAndReadConfigFile(Utils.java:138)    at backtype.storm.utils.Utils.readStormConfig(Utils.java:178)    at backtype.storm.config$read_storm_config.invoke(config.clj:116)    at backtype.storm.command.config_value$_main.invoke(config_value.clj:22)    at clojure.lang.AFn.applyToHelper(AFn.java:161)    at clojure.lang.AFn.applyTo(AFn.java:151)    at backtype.storm.command.config_value.main(Unknown Source)Exception in thread "main" expected '<document start>', but found BlockMappingStart in 'reader', line 43, column 1:    supervisor.slots.ports:    ^    at org.yaml.snakeyaml.parser.ParserImpl$ParseDocumentStart.produce(ParserImpl.java:225)    at org.yaml.snakeyaml.parser.ParserImpl.peekEvent(ParserImpl.java:158)    at org.yaml.snakeyaml.parser.ParserImpl.checkEvent(ParserImpl.java:143)    at org.yaml.snakeyaml.composer.Composer.getSingleNode(Composer.java:108)    at org.yaml.snakeyaml.constructor.BaseConstructor.getSingleData(BaseConstructor.java:120)    at org.yaml.snakeyaml.Yaml.loadFromReader(Yaml.java:481)    at org.yaml.snakeyaml.Yaml.load(Yaml.java:424)    at backtype.storm.utils.Utils.findAndReadConfigFile(Utils.java:138)    at backtype.storm.utils.Utils.readStormConfig(Utils.java:178)    at backtype.storm.config$read_storm_config.invoke(config.clj:116)    at backtype.storm.command.config_value$_main.invoke(config_value.clj:22)    at clojure.lang.AFn.applyToHelper(AFn.java:161)    at clojure.lang.AFn.applyTo(AFn.java:151)    at backtype.storm.command.config_value.main(Unknown Source)

在给配置文件加上空格后，问题消失，正常启动,如下：没行参数前都要空出一格。

# Licensed to the Apache Software Foundation (ASF) under one# or more contributor license agreements.  See the NOTICE file# distributed with this work for additional information# regarding copyright ownership.  The ASF licenses this file# to you under the Apache License, Version 2.0 (the# "License"); you may not use this file except in compliance# with the License.  You may obtain a copy of the License at## http://www.apache.org/licenses/LICENSE-2.0## Unless required by applicable law or agreed to in writing, software# distributed under the License is distributed on an "AS IS" BASIS,# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.# See the License for the specific language governing permissions and# limitations under the License.########### These MUST be filled in for a storm configuration storm.zookeeper.servers:     - "h1"     - "h2"     - "h3" nimbus.host: "h1"# #temporary change to 8081 ui.port: 8080# # # ##### These may optionally be filled in:#    ## List of custom serializations# topology.kryo.register:#     - org.mycompany.MyType#     - org.mycompany.MyType2: org.mycompany.MyType2Serializer### List of custom kryo decorators# topology.kryo.decorators:#     - org.mycompany.MyDecorator### Locations of the drpc servers#drpc.servers:#  - "drpc-server"#supervisor.slots.ports:#  - 6700#  - 6701#  - 6702#  - 6703## Metrics Consumers# topology.metrics.consumer.register:#   - class: "backtype.storm.metrics.LoggingMetricsConsumer"#     parallelism.hint: 1#   - class: "org.mycompany.MyMetricsConsumer"#     parallelism.hint: 1#     argument:#       - endpoint: "metrics-collector.mycompany.org"#storm.local.dir: "/home/storm/storm-0.9.1" storm.scheduler: "backtype.storm.scheduler.ResaScheduler" worker.childopts: "-Xmx4096m" supervisor.heartbeat.frequency.secs: 10 worker.heartbeat.frequency.secs: 5 task.heartbeat.frequency.secs: 5 task.refresh.poll.secs: 3 topology.receiver.buffer.size: 1 topology.max.spout.pending: 200 topology.executor.send.buffer.size: 65536 topology.executor.receive.buffer.size: 65536 worker.cpu.limit: 200

这里要给大家提个醒：在配置Storm时，最好不要改动原来的格式，你只需要在相关的地方加上你要用的东西即可。尤其是空格，多一个，少一个，系统可能都会提示识别的错误，也让人感觉到匪夷所思。