1#!/usr/bin/python -B
2
3# Copyright 2017 The Android Open Source Project
4#
5# Licensed under the Apache License, Version 2.0 (the "License");
6# you may not use this file except in compliance with the License.
7# You may obtain a copy of the License at
8#
9#      http://www.apache.org/licenses/LICENSE-2.0
10#
11# Unless required by applicable law or agreed to in writing, software
12# distributed under the License is distributed on an "AS IS" BASIS,
13# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14# See the License for the specific language governing permissions and
15# limitations under the License.
16
17"""Downloads the latest IANA time zone files."""
18
19import argparse
20import ftplib
21import os
22import shutil
23import subprocess
24import sys
25
26sys.path.append('%s/external/icu/tools' % os.environ.get('ANDROID_BUILD_TOP'))
27import i18nutil
28import tzdatautil
29
30# Calculate the paths that are referred to by multiple functions.
31android_build_top = i18nutil.GetAndroidRootOrDie()
32iana_data_dir = os.path.realpath('%s/system/timezone/input_data/iana' % android_build_top)
33iana_tools_dir = os.path.realpath('%s/system/timezone/input_tools/iana' % android_build_top)
34
35def FtpRetrieveFile(ftp, filename):
36  ftp.retrbinary('RETR %s' % filename, open(filename, 'wb').write)
37
38
39def CheckSignature(data_filename, signature_filename):
40  """Checks the signature of a file."""
41  print 'Verifying signature of %s using %s...' % (data_filename, signature_filename)
42  try:
43    subprocess.check_call(['gpg', '--trusted-key=ED97E90E62AA7E34', '--verify',
44                          signature_filename, data_filename])
45  except subprocess.CalledProcessError as err:
46    print 'Unable to verify signature'
47    print '\n\n******'
48    print 'If this fails for you, you probably need to import Paul Eggert''s public key:'
49    print '  gpg --receive-keys ED97E90E62AA7E34'
50    print '******\n\n'
51    raise
52
53
54def FindLatestRemoteTar(ftp, file_prefix):
55  iana_tar_filenames = []
56
57  for filename in ftp.nlst():
58    if "/" in filename:
59      print "FTP server returned bogus file name"
60      sys.exit(1)
61
62    if filename.startswith(file_prefix) and filename.endswith('.tar.gz'):
63      iana_tar_filenames.append(filename)
64
65  iana_tar_filenames.sort(reverse=True)
66
67  if len(iana_tar_filenames) == 0:
68    print 'No files found'
69    sys.exit(1)
70
71  return iana_tar_filenames[0]
72
73
74def DownloadAndReplaceLocalFiles(file_prefixes, ftp, local_dir):
75  output_files = []
76
77  for file_prefix in file_prefixes:
78    latest_iana_tar_filename = FindLatestRemoteTar(ftp, file_prefix)
79    local_iana_tar_file = tzdatautil.GetIanaTarFile(local_dir, file_prefix)
80    if local_iana_tar_file:
81      local_iana_tar_filename = os.path.basename(local_iana_tar_file)
82      if latest_iana_tar_filename <= local_iana_tar_filename:
83        print('Latest remote file for %s is called %s and is older or the same as'
84              ' current local file %s'
85              % (local_dir, latest_iana_tar_filename, local_iana_tar_filename))
86        continue
87
88    print 'Found new %s* file for %s: %s' % (file_prefix, local_dir, latest_iana_tar_filename)
89    i18nutil.SwitchToNewTemporaryDirectory()
90
91    print 'Downloading file %s...' % latest_iana_tar_filename
92    FtpRetrieveFile(ftp, latest_iana_tar_filename)
93
94    signature_filename = '%s.asc' % latest_iana_tar_filename
95    print 'Downloading signature %s...' % signature_filename
96    FtpRetrieveFile(ftp, signature_filename)
97
98    CheckSignature(latest_iana_tar_filename, signature_filename)
99
100    new_local_iana_tar_file = '%s/%s' % (local_dir, latest_iana_tar_filename)
101    shutil.copyfile(latest_iana_tar_filename, new_local_iana_tar_file)
102    new_local_signature_file = '%s/%s' % (local_dir, signature_filename)
103    shutil.copyfile(signature_filename, new_local_signature_file)
104
105    output_files.append(new_local_iana_tar_file)
106    output_files.append(new_local_signature_file)
107
108    # Delete the existing local IANA tar file, if there is one.
109    if local_iana_tar_file:
110      os.remove(local_iana_tar_file)
111
112    local_signature_file = '%s.asc' % local_iana_tar_file
113    if os.path.exists(local_signature_file):
114      os.remove(local_signature_file)
115
116  return output_files
117
118# Run from any directory after having run source/envsetup.sh / lunch
119# See http://www.iana.org/time-zones/ for more about the source of this data.
120def main():
121  parser = argparse.ArgumentParser(description=('Update IANA files from upstream'))
122  parser.add_argument('--tools', help='Download tools files', action='store_true')
123  parser.add_argument('--data', help='Download data files', action='store_true')
124  args = parser.parse_args()
125  if not args.tools and not args.data:
126    parser.error("Nothing to do")
127    sys.exit(1)
128
129  print 'Looking for new IANA files...'
130
131  ftp = ftplib.FTP('ftp.iana.org')
132  ftp.login()
133  ftp.cwd('tz/releases')
134
135  output_files = []
136  if args.tools:
137    # The tools and data files are kept separate to make the updates independent.
138    # This means we duplicate the tzdata20xx file (once in the tools dir, once
139    # in the data dir) but the contents of the data tar appear to be needed for
140    # the zic build.
141    new_files = DownloadAndReplaceLocalFiles(['tzdata20', 'tzcode20'], ftp, iana_tools_dir)
142    output_files += new_files
143  if args.data:
144    new_files = DownloadAndReplaceLocalFiles(['tzdata20'], ftp, iana_data_dir)
145    output_files += new_files
146
147  if len(output_files) == 0:
148    print 'No files updated'
149  else:
150    print 'New files:'
151    for output_file in output_files:
152      print '  %s' % output_file
153
154
155if __name__ == '__main__':
156  main()
157