在python版本的Google App Engine mapreduce中,如何从done_callback访问计数器？

Question

我正在使用Google App Engine mapreduce来分析一些数据.我正在生成一些计数器,我想在我的done_callback中创建一个简单的Google图表.如何从回调中访问结果计数器？

#The map method
def count_created_since(entity):
  now = datetime.datetime.now()
  delta = now-entity.created

  #analyze last 12 weeks
  for x in range(12):
    start = 7*x
    stop = 7*(x+1)

    if delta.days >= start and delta.days < stop:
      #The counters
      yield op.counters.Increment(str(x)+" weeks ago")


def my_callback(request):
  # fetch counter results to create a simple Google chart url

Answer 1

您可以通过访问计数器MapreduceState的 counter_map属性.

from mapreduce import model
state = model.MapreduceState.get_by_job_id(your_job_id)
# counters live in state.counters_map

有一个讨论的邮件列表上大约每月访问计数器多前.