sdk/python/arvados/_normalize_stream.py

   1 def normalize_stream(stream_name, stream):
   2     """Take manifest stream and return a list of tokens in normalized format.
   3
   4     :stream_name:
   5       The name of the stream.
   6
   7     :stream:
   8       A dict mapping each filename to a list of `_range.LocatorAndRange` objects.
   9
  10     """
  11
  12     stream_tokens = [stream_name]
  13     sortedfiles = list(stream.keys())
  14     sortedfiles.sort()
  15
  16     blocks = {}
  17     streamoffset = 0L
  18     # Go through each file and add each referenced block exactly once.
  19     for streamfile in sortedfiles:
  20         for segment in stream[streamfile]:
  21             if segment.locator not in blocks:
  22                 stream_tokens.append(segment.locator)
  23                 blocks[segment.locator] = streamoffset
  24                 streamoffset += segment.block_size
  25
  26     # Add the empty block if the stream is otherwise empty.
  27     if len(stream_tokens) == 1:
  28         stream_tokens.append(config.EMPTY_BLOCK_LOCATOR)
  29
  30     for streamfile in sortedfiles:
  31         # Add in file segments
  32         current_span = None
  33         fout = streamfile.replace(' ', '\\040')
  34         for segment in stream[streamfile]:
  35             # Collapse adjacent segments
  36             streamoffset = blocks[segment.locator] + segment.segment_offset
  37             if current_span is None:
  38                 current_span = [streamoffset, streamoffset + segment.segment_size]
  39             else:
  40                 if streamoffset == current_span[1]:
  41                     current_span[1] += segment.segment_size
  42                 else:
  43                     stream_tokens.append("{0}:{1}:{2}".format(current_span[0], current_span[1] - current_span[0], fout))
  44                     current_span = [streamoffset, streamoffset + segment.segment_size]
  45
  46         if current_span is not None:
  47             stream_tokens.append("{0}:{1}:{2}".format(current_span[0], current_span[1] - current_span[0], fout))
  48
  49         if not stream[streamfile]:
  50             stream_tokens.append("0:0:{0}".format(fout))
  51
  52     return stream_tokens