sdk/python/arvados/crunch.py

   1 from builtins import object
   2 import json
   3 import os
   4
   5 class TaskOutputDir(object):
   6     """Keep-backed directory for staging outputs of Crunch tasks.
   7
   8     Example, in a crunch task whose output is a file called "out.txt"
   9     containing "42":
  10
  11         import arvados
  12         import arvados.crunch
  13         import os
  14
  15         out = arvados.crunch.TaskOutputDir()
  16         with open(os.path.join(out.path, 'out.txt'), 'w') as f:
  17             f.write('42')
  18         arvados.current_task().set_output(out.manifest_text())
  19     """
  20     def __init__(self):
  21         self.path = os.environ['TASK_KEEPMOUNT_TMP']
  22
  23     def __str__(self):
  24         return self.path
  25
  26     def manifest_text(self):
  27         snapshot = os.path.join(self.path, '.arvados#collection')
  28         return json.load(open(snapshot))['manifest_text']