src/native_client/build/package_version/revision_info.py

   1 #!/usr/bin/python
   2 # Copyright (c) 2014 The Native Client Authors. All rights reserved.
   3 # Use of this source code is governed by a BSD-style license that can be
   4 # found in the LICENSE file.
   5
   6 """Encompasses a revision file of a package.
   7
   8 A revision file associates an SVN revision with a package. The revision
   9 file will encompass the package information for all package targets. All
  10 packages must have already been built by the buildbot before a revision file
  11 can be made for it.
  12 """
  13
  14 import hashlib
  15 import json
  16
  17 import archive_info
  18 import error
  19 import package_info
  20 import packages_info
  21
  22
  23 FIELD_PACKAGE_NAME = 'package_name'
  24 FIELD_REVISION = 'revision'
  25 FIELD_PACKAGE_TARGETS = 'package_targets'
  26
  27 FIELD_REVISION_HASH = 'revision_hash'
  28
  29
  30 class RevisionInfo(object):
  31   """Revision information object describing a set revision for a package."""
  32   def __init__(self, packages_desc, revision_file=None):
  33     """Constructor for a RevisionInfo object.
  34
  35     Args:
  36       packages_desc: Packages description containing all the necessary packages
  37                      and package targets to verify a revision file is complete.
  38       revision_file: Optional JSON file representing a RevisionInfo object.
  39     """
  40     assert isinstance(packages_desc, packages_info.PackagesInfo)
  41     self._packages_desc = packages_desc
  42     self._revision_num = -1
  43     self._package_name = None
  44
  45     # A revision describes all the package_info's for each package target.
  46     # Every package target in the package_desc must have its revision set
  47     # for the revision info to be valid.
  48     self._package_targets = {}
  49
  50     if revision_file is not None:
  51       self.LoadRevisionFile(revision_file)
  52
  53   def __eq__(self, other):
  54     return (type(self) == type(other) and
  55             self._revision_num == other._revision_num and
  56             self._package_name == other._package_name and
  57             self._package_targets == other._package_targets)
  58
  59   def _GetRevisionHash(self):
  60     """Returns a stable hash for a revision file for validation purposes."""
  61     hash_string = str(self._revision_num)
  62     hash_string += str(self._package_name)
  63     for package_target in sorted(self._package_targets):
  64       package_desc = self._package_targets[package_target]
  65       archive_list = package_desc.GetArchiveList()
  66
  67       hash_string += str(package_target)
  68       for archive in archive_list:
  69         for field, member in archive.GetArchiveData()._asdict().iteritems():
  70           hash_string += '[%s:%s]' % (field, member)
  71
  72     return hashlib.sha1(hash_string).hexdigest()
  73
  74   def _ValidateRevisionComplete(self):
  75     """Validate packages to make sure it matches the packages description."""
  76     if self._package_name is None:
  77       raise error.Error('Invalid revision information - '
  78                                   'no package name.')
  79     elif self._revision_num == -1:
  80       raise error.Error('Invalid revision information - '
  81                                   'no revision number')
  82
  83     package_targets = self._packages_desc.GetPackageTargetsForPackage(
  84         self._package_name
  85     )
  86
  87     if package_targets:
  88       package_targets = set(package_targets)
  89       revision_targets = set(self._package_targets.keys())
  90
  91       if package_targets != revision_targets:
  92         raise error.Error('Invalid revision information - '
  93                            'target mismatch:'
  94                            + '\n%s:' % self._package_name
  95                            + '\n  Required Target Packages:'
  96                            + '\n\t' + '\n\t'.join(sorted(package_targets))
  97                            + '\n  Supplied Target Packages:'
  98                            + '\n\t' + '\n\t'.join(sorted(revision_targets)))
  99
 100   def LoadRevisionFile(self, revision_file, skip_hash_verify=False):
 101     """Loads a revision JSON file into this object.
 102
 103     Args:
 104       revision_file: File name for a revision JSON file.
 105       skip_hash_verify: If True, will skip the hash validation check. This
 106                         should only be used if a field has been added or
 107                         removed in order to recalculate the revision hash.
 108     """
 109     try:
 110       with open(revision_file, 'rt') as f:
 111         revision_json = json.load(f)
 112
 113       self._package_name = revision_json[FIELD_PACKAGE_NAME]
 114       self._revision_num = revision_json[FIELD_REVISION]
 115       self._package_targets = {}
 116
 117       package_targets = revision_json[FIELD_PACKAGE_TARGETS]
 118       for package_target, archive_list in package_targets.iteritems():
 119         self._package_targets[package_target] = package_info.PackageInfo(
 120             archive_list
 121         )
 122     except (TypeError, KeyError) as e:
 123       raise error.Error('Invalid revision file [%s]: %s' %
 124                                   (revision_file, e))
 125
 126     self._ValidateRevisionComplete()
 127
 128     if not skip_hash_verify:
 129       hash_value = revision_json[FIELD_REVISION_HASH]
 130       if self._GetRevisionHash() != hash_value:
 131         raise error.Error('Invalid revision file [%s] - revision hash check '
 132             'failed' % revision_file)
 133
 134   def SaveRevisionFile(self, revision_file):
 135     """Saves this object to a revision JSON file to be loaded later.
 136
 137     Args:
 138       revision_file: File name where revision JSON file will be saved.
 139     """
 140     self._ValidateRevisionComplete()
 141
 142     package_targets = {}
 143     for package_target, package_desc in self._package_targets.iteritems():
 144       package_targets[package_target] = package_desc.DumpPackageJson()
 145
 146     revision_json = {
 147         FIELD_PACKAGE_NAME: self._package_name,
 148         FIELD_REVISION: self._revision_num,
 149         FIELD_PACKAGE_TARGETS: package_targets,
 150         FIELD_REVISION_HASH: self._GetRevisionHash()
 151     }
 152
 153     with open(revision_file, 'wt') as f:
 154       json.dump(revision_json, f, sort_keys=True,
 155                 indent=2, separators=(',', ': '))
 156
 157   def SetRevisionNumber(self, revision_num):
 158     """Sets the current revision number for this object."""
 159     self._revision_num = revision_num
 160
 161   def GetRevisionNumber(self):
 162     """Gets the currently set revision number for this object."""
 163     return self._revision_num
 164
 165   def ClearRevisions(self):
 166     """Clears all package information for this object"""
 167     self._package_name = None
 168     self._package_targets = {}
 169
 170   def SetTargetRevision(self, package_name, package_target, package_desc):
 171     """Sets a package description for a package target.
 172
 173     The package description is a package_info object representing the package
 174     for this particular revision.
 175
 176     Args:
 177       package_name: Name of the package this revision object represents.
 178       package_target: Package target name for the package we are setting.
 179       package_desc: package_info object representing the package target.
 180     """
 181     if self._package_name is None:
 182       self._package_name = package_name
 183     elif self._package_name != package_name:
 184       raise error.Error('Revision information must be all for the '
 185                         'same package\n'
 186                         'Original package name: %s\nNew package name: %s'
 187                         % (self._package_name, package_name))
 188     self._package_targets[package_target] = package_desc
 189
 190   def GetPackageInfo(self, package_target):
 191     """Gets the package description for a particular package target.
 192
 193     The package description is a package_info object representing the package
 194     for this particular revision.
 195
 196     Args:
 197       package_target: Package target name for which we want the package info.
 198
 199     Returns:
 200       A package_info object for the package target, or None for invalid targets.
 201     """
 202     return self._package_targets.get(package_target, None)