cvs2svn_lib/revision_manager.py

   1 # (Be in -*- python -*- mode.)
   2 #
   3 # ====================================================================
   4 # Copyright (c) 2000-2008 CollabNet.  All rights reserved.
   5 #
   6 # This software is licensed as described in the file COPYING, which
   7 # you should have received as part of this distribution.  The terms
   8 # are also available at http://subversion.tigris.org/license-1.html.
   9 # If newer versions of this license are posted there, you may use a
  10 # newer version instead, at your option.
  11 #
  12 # This software consists of voluntary contributions made by many
  13 # individuals.  For exact contribution history, see the revision
  14 # history and logs, available at http://cvs2svn.tigris.org/.
  15 # ====================================================================
  16
  17 """This module describes the interface to the CVS repository."""
  18
  19
  20 class RevisionCollector(object):
  21   """Optionally collect revision information for CVS files."""
  22
  23   def __init__(self):
  24     """Initialize the RevisionCollector.
  25
  26     Please note that a RevisionCollector is instantiated in every
  27     program run, even if the data-collection pass will not be
  28     executed.  (This is to allow it to register the artifacts that it
  29     produces.)  Therefore, the __init__() method should not do much,
  30     and more substantial preparation for use (like actually creating
  31     the artifacts) should be done in start()."""
  32
  33     pass
  34
  35   def register_artifacts(self, which_pass):
  36     """Register artifacts that will be needed while collecting data.
  37
  38     WHICH_PASS is the pass that will call our callbacks, so it should
  39     be used to do the registering (e.g., call
  40     WHICH_PASS.register_temp_file() and/or
  41     WHICH_PASS.register_temp_file_needed())."""
  42
  43     pass
  44
  45   def start(self):
  46     """Data will soon start being collected.
  47
  48     Any non-idempotent initialization should be done here."""
  49
  50     pass
  51
  52   def process_file(self, cvs_file_items):
  53     """Collect data for the file described by CVS_FILE_ITEMS.
  54
  55     CVS_FILE_ITEMS has already been transformed into the logical
  56     representation of the file's history as it should be output.
  57     Therefore it is not necessarily identical to the history as
  58     recorded in the RCS file."""
  59
  60     raise NotImplementedError()
  61
  62   def finish(self):
  63     """All recording is done; clean up."""
  64
  65     pass
  66
  67
  68 class NullRevisionCollector(RevisionCollector):
  69   """A do-nothing variety of RevisionCollector."""
  70
  71   def process_file(self, cvs_file_items):
  72     pass
  73
  74
  75 class RevisionReader(object):
  76   """An object that can read the contents of CVSRevisions."""
  77
  78   def register_artifacts(self, which_pass):
  79     """Register artifacts that will be needed during branch exclusion.
  80
  81     WHICH_PASS is the pass that will call our callbacks, so it should
  82     be used to do the registering (e.g., call
  83     WHICH_PASS.register_temp_file() and/or
  84     WHICH_PASS.register_temp_file_needed())."""
  85
  86     pass
  87
  88   def start(self):
  89     """Prepare for calls to get_content_stream."""
  90
  91     pass
  92
  93   def get_content_stream(self, cvs_rev, suppress_keyword_substitution=False):
  94     """Return a file-like object from which the contents of CVS_REV
  95     can be read.
  96
  97     CVS_REV is a CVSRevision.  If SUPPRESS_KEYWORD_SUBSTITUTION is
  98     True, then suppress the substitution of RCS/CVS keywords in the
  99     output."""
 100
 101     raise NotImplementedError
 102
 103   def finish(self):
 104     """Inform the reader that all calls to get_content_stream are done.
 105     Start may be called again at a later point."""
 106
 107     pass
 108
 109