Question

我有Flume代理配置，我使用HTTPSource从特定服务接收事件数据。出于测试目的，我在Python中创建静态JSON结构作为一个名为data的字符串对象（参见下面的代码片段1）并将对象发送到带有正确标题的水槽但是然后flume返回给我一个400错误的请求错误所有时间（见下面的摘录2）。相关的水槽执行异常消息已在下面的代码段3中提供。

问题：有人能告诉我我的静态json请求有什么问题会导致flume HTTPSource拒绝吗？还有其他问题我可能会丢失，这与json数据无关吗？感谢。

SNIPPET 1（Python脚本生成包含我的静态JSON数据的虚拟HTTP请求）

 import urllib2, json

 serviceName = "serviceA"
 timestamp = datetime.datetime.strftime(datetime.datetime.now(), '%Y-%m-%d %H:%M:%S')

 body = "{ \"service\":\"" + serviceName + "\" }"
 print("BODY: " +  body)

 //My JSON data
 data = "[{ \"headers\" : { \"timestamp\" : \"" + timestamp + "\" }, \"body\" : " + body + " }]"
 print("DATA: "  + data)

 req = urllib2.Request("http://10.1.0.100:5140")
 req.add_header('Content-Type', 'application/json')
 response = urllib2.urlopen(req, data)

SNIPPET 2 - python脚本的执行输出

  BODY: { "service":"serviceA" }
  DATA: [{ "headers" : { "timestamp" : "2016-01-13 12:26:48" }, "body" : { "service":"serviceA" } }]
  Traceback (most recent call last):
  File "./event_data_gen.py", line 57, in <module>
  response = urllib2.urlopen(req, data)  
  File "/usr/lib/python2.7/urllib2.py", line 127, in urlopen
  return _opener.open(url, data, timeout)
  File "/usr/lib/python2.7/urllib2.py", line 410, in open
  response = meth(req, response)
  File "/usr/lib/python2.7/urllib2.py", line 523, in http_response
  'http', request, response, code, msg, hdrs)
  File "/usr/lib/python2.7/urllib2.py", line 448, in error
  return self._call_chain(*args)
  File "/usr/lib/python2.7/urllib2.py", line 382, in _call_chain
  result = func(*args)
  File "/usr/lib/python2.7/urllib2.py", line 531, in http_error_default
  raise HTTPError(req.get_full_url(), code, msg, hdrs, fp)
  urllib2.HTTPError: HTTP Error 400: Bad request from client. 
  Request has invalid JSON Syntax.

SNIPPET 3 - Flume执行输出中的异常消息

  2016-01-13 12:26:48,653 (34313572@qtp-604003190-13)
  [WARN -     org.apache.flume.source.http.HTTPSource$FlumeHTTPServlet.doPost(HTTPSource.java:      242)] Received bad request from client. 
  org.apache.flume.source.http.HTTPBadRequestException: Request has invalid JSON Syntax.
  at org.apache.flume.source.http.JSONHandler.getEvents(JSONHandler.java:119)
  at  org.apache.flume.source.http.HTTPSource$FlumeHTTPServlet.doPost(HTTPSource.java:240)
  at javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
  at javax.servlet.http.HttpServlet.service(HttpServlet.java:814)
  at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
  at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:401)
  at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
  at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
  at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:766)
  at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
  at org.mortbay.jetty.Server.handle(Server.java:326)
  at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
  at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:945)
  at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:756)
  at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)
  at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
  at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)
  at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
  Caused by: com.google.gson.JsonSyntaxException:  java.lang.IllegalStateException: Expected a string but was BEGIN_OBJECT at line  1 column 67
  at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:176)
  at com.google.gson.internal.bind.TypeAdapterRuntimeTypeWrapper.read(TypeAdapterRuntimeTypeWrapper.java:40)
  at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:81)
  at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:60)
  at com.google.gson.Gson.fromJson(Gson.java:795)
  at com.google.gson.Gson.fromJson(Gson.java:761)
  at org.apache.flume.source.http.JSONHandler.getEvents(JSONHandler.java:117)
... 17 more
  Caused by: java.lang.IllegalStateException: Expected a string but was  BEGIN_OBJECT at line 1 column 67
  at com.google.gson.stream.JsonReader.nextString(JsonReader.java:464)
  at com.google.gson.internal.bind.TypeAdapters$13.read(TypeAdapters.java:349)
  at com.google.gson.internal.bind.TypeAdapters$13.read(TypeAdapters.java:337)
  at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.read(ReflectiveTypeAdapterFactory.java:93)
  at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:172)

Answer 1

正如@Martyn W在他的评论中指出的那样，JSONHandler期望并验证JSON具有某种结构。

JavaDocs of JSONHandler：

中对此进行了描述

用于接受一系列事件的HTTPSource的JSONHandler。这个   如果反序列化由于错误而失败，则handler会抛出异常   格式或任何其他原因。每个事件都必须编码为地图   两个键值对。



标头 - 此键值对的键是“标头”。此键的值是另一个映射，表示事件标题。这些   标题按原样插入到Flume事件中。



body - body是一个表示事件正文的字符串。这个键值对的关键是“body”。所有键值对都是   被认为是标题。一个例子：


[{“headers”：{“a”：“b”，“c”：“d”}，“body”：“random_body”}，{“header”：   {“e”：“f”}，“body”：“random_body2”}]

由于格式错误，Flume HTTPSource拒绝JSON正文

1 个答案: