为什么我的火花流媒体应用程序没有显示任何输出

Question

这是我之前的堆栈溢出问题的后续question，我没有收到回复

我试过写这个，这不会引起任何错误，但它没有显示任何输出

我的目标是使用历史数据RDD评估Dstream对象，我无法

找到像这样的pyspark的任何示例（使用静态RDD检查流式RDD

手工创建）。感谢您的回复。谢谢

"""
Created on Thu May 05 16:23:15 2016

@author: bghosh
"""
import re
from pyspark import SparkContext
from pyspark.streaming import StreamingContext
from pyspark.sql import SQLContext,functions as func,Row


sc = SparkContext("local[2]", "realtimeApp")
sqlContext = SQLContext(sc)
ssc = StreamingContext(sc,10)
files = ssc.textFileStream("hdfs://RealTimeInputFolder/")

########Lets get the data from the db which is relavant for streaming ###

driver = "com.microsoft.sqlserver.jdbc.SQLServerDriver"
dataurl = "jdbc:sqlserver://devserver:1433"
db = "devDB"
table = "stream_helper"
credential = "dev_credential"

########basic data for evaluation purpose ########

#base_data = sqlContext.read.format("jdbc").options(driver=driver,url=dataurl,database=db,user=credential,password=credential,dbtable=table).load()

base_data = sqlContext.read.format("jdbc").options(driver=driver,url=dataurl,database=db,user=credential,password=credential,dbtable=table).load()
base_data.registerTempTable("base_data")

######
files_count = files.flatMap(lambda file: file.split( ))

#pattern =  '(TranAmount=Decimal.{2})(.[0-9]*.[0-9]*)(\\S+ )(TranDescription=u.)([a-zA-z\\s]+)([\\S\\s]+ )(dSc=u.)([A-Z]{2}.[0-9]+)'


tranfiles = "wasb://vanspark01@vanspark01.blob.core.windows.net/RealTimeInputFolder01/"

def getSqlContextInstance(sparkContext):
    if ('sqlContextSingletonInstance' not in globals()):
        globals()['sqlContextSingletonInstance'] = SQLContext(sparkContext)
    return globals()['sqlContextSingletonInstance']

def preparse(logline):
    #match = re.search(pattern,logline)
    pre = logline.split(",")


    return(
    Row(
    Customer_id = pre[-1],
    trantype = pre[-4],
    amount = float(pre[-5]))
    )



def parse():
    parsed_tran = ssc.textFileStream(tranfiles).map(preparse)
    #success = parsed_tran.filter(lambda s: s[1] == 1).map(lambda x:x[0])

    #fail = parsed_tran.filter(lambda s:s[1] == 0).map(lambda x:x[0])
    """if fail.count() > 0:
        print "no of non parsed file : %d",fail.count()
    """
    return parsed_tran#success


def check_historic(rdd):

    #checking with the historical table #
    try:
        streamSqlcontext = getSqlContextInstance(rdd)
        stream_df = streamSqlcontext.createDataFrame(rdd)
        stream_df.registerTempTable("stream_df")
        result_data_frame = streamSqlcontext.sql("select * from stream_df LEFT OUTER JOIN base_data on stream_df.Customer_id= base_data.Customer_id"  )
        result_data_frame.show()

    except:
        pass
    #return result_data_frame.rdd


success = parse()

success.foreachRDD(check_historic)
ssc.start()
ssc.awaitTermination()