迪斯科链条跳过减少

时间:2015-12-31 04:40:49

标签: python mapreduce disco

我最近发现Disco Project并且与Hadoop相比真的很喜欢它,但我遇到了问题。我的项目设置如此(如果有帮助的话,我会很乐意剪切/粘贴真实代码):

myfile.py

from disco.core import Job, result_iterator
import collections, sys
from disco.worker.classic.func import chain_reader
from disco.worker.classic.worker import Params

def helper1():
   #do stuff

def helper2():
   #do stuff
.
.
.
def helperN():
   #do stuff

class A(Job):
   @staticmethod
   def map_reader(fd, params):
      #Read input file
      yield line

   def map(self, line, params):
      #Process lines into dictionary
      #Iterate dictionary
          yield k, v

   def reduce(self, iter, out, params):
      #iterate iter
      #Process k, v into dictionary, aggregating values
      #Process dictionry
      #Iterate dictionary
         out.add(k,v)

Class B(Job):

   map_reader = staticmethod(chain_reader)
   map = staticmethod(nop_map)

   reduce(self, iter, out, params):
      #Process iter
      #iterate results
         out.add(k,v)


if __name__ == '__main__':
   from myfile import A, B
   job1 = A().run(input=[input_filename], params=Params(k=k))
   job2 = B().run(input=[job1.wait()], params=Params(k=k))
   with open(output_filename, 'w') as fp:
        for count, line in result_iterator(job2.wait(show=True)):
            fp.write(str(count) + ',' + line + '\n')

我的问题是工作流程完全跳过A的减少,然后降到B的减少。

这里有什么想法?

1 个答案:

答案 0 :(得分:0)

这是一个简单而微妙的问题:我没有

show = True

for job1。出于某种原因,对于job2的show set,它向我展示了来自job1的map()和map-shuffle()步骤,所以因为我没有得到我期望的最终结果并输入其中一个job2函数看起来错误,我得出的结论是job1步骤没有正常运行(在我添加job2之前,我进一步支持这一点,我验证了job1输出的准确性)。