fetch-debian-changelog

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# Packaging Scripts
# Copyright (C) 2021-2024 by Thomas Dreibholz
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# Contact: dreibh@simula.no
#

import glob
import os
import re
import shutil
import subprocess
import sys
import tempfile
import time
import urllib.error
import urllib.request


#  ====== Handle arguments ==================================================
if len(sys.argv) < 2:
  sys.stderr.write('Usage: ' + sys.argv[0] + ' package [distribution]\n')
  sys.exit(1)

debianPackage       = sys.argv[1]
if len(sys.argv) == 2:
   debianDistribution  = 'unstable'
else:
   debianDistribution  = sys.argv[2]
if debianDistribution in [ 'unstable', 'testing', 'stable', 'oldstable' ]:
   # Debian
   statusPageURL = 'https://packages.debian.org/source/' + debianDistribution + '/' + debianPackage
else:
   # Ubuntu
   statusPageURL = 'https://packages.ubuntu.com/source/' + debianDistribution + '/' + debianPackage

debianVersion       = None
debianLocation      = None
debianArchive       = None
debianArchiveFormat = None


# ====== Get package status =================================================
statusPageContents = None
sys.stderr.write('Looking for package status on ' + statusPageURL + ' ... ')
sys.stderr.flush()
try:
   statusPage = urllib.request.urlopen(statusPageURL)
   statusPageContents = statusPage.readlines()
   statusPage.close()

   re_debian_package = re.compile(r'.*Source Package: ' + debianPackage + ' \(([0-9-+~\.a-z]+)\)')
   re_debian_archive = re.compile(r'.*href="((http|https)://[a-zA-Z0-9\./+-]+/' + \
                                     debianPackage[0:1] + '/' + \
                                     debianPackage + '/' + \
                                     r')(' + debianPackage + r'_[0-9-+~\.a-z]+\.debian\.tar\.[a-zA-Z]+)"')
   for line in statusPageContents:
      line = line.decode('utf-8')
      match = re_debian_package.match(line)
      if match != None:
         debianVersion = match.group(1)
      else:
         match = re_debian_archive.match(line)
         if match != None:
            debianLocation = match.group(1)
            debianArchive  = match.group(3)

except urllib.error.HTTPError as e:
   sys.stderr.write('not found (HTTP ' + str(e.code) + ')!\n')
   sys.exit(1)

if (debianVersion == None) or (debianArchive == None):
   sys.stderr.write('not found!\n')
   sys.exit(1)

sys.stderr.write('Version in ' + debianDistribution + ' is ' + debianVersion + '\n')


# ====== Determine necessary compression option =============================
debianArchiveFormat = debianArchive[len(debianArchive) - 2 : len(debianArchive)]
tarCompressionOption = ''
if debianArchiveFormat == 'gz':
   tarCompressionOption = 'z'
elif debianArchiveFormat == 'bz2':
   tarCompressionOption = 'j'
elif debianArchiveFormat == 'xz':
   tarCompressionOption = 'J'


# ====== Fetch debian archive ===============================================
archiveFileURL =  debianLocation + debianArchive
sys.stderr.write('Looking for \"debian\" archive at ' + archiveFileURL + ' ... ')
sys.stderr.flush()
try:
   archiveFile = urllib.request.urlopen(archiveFileURL)
   debianArchiveFile = tempfile.NamedTemporaryFile(delete=False)
   shutil.copyfileobj(archiveFile, debianArchiveFile)
   debianArchiveFile.close()
   archiveFile.close()
   sys.stderr.write('found!\n')

   try:

      process = subprocess.run([ 'tar', 'x' + tarCompressionOption + 'fO', debianArchiveFile.name, 'debian/changelog'],
                              stderr=subprocess.PIPE, check=True, universal_newlines=True)

      os.unlink(debianArchiveFile.name)

   except Exception as e:
      sys.stderr.write('ERROR: Failed to extract debian/changelog from ' + debianArchiveFile.name + ': ' + str(e) + '\n')
      sys.exit(1)

except urllib.error.HTTPError as e:
   sys.stderr.write('not found (HTTP ' + str(e.code) + ')!\n')
   sys.exit(1)