wizard/command/upgrade.py

   1 import sys
   2 import distutils.version
   3 import os
   4 import shutil
   5 import logging.handlers
   6 import tempfile
   7 import itertools
   8
   9 from wizard import app, command, deploy, scripts, shell, util
  10
  11 kib_buffer = 1024 * 30 # 30 MiB we will always leave available
  12 errno_blacklisted = 64
  13
  14 def main(argv, baton):
  15     options, args = parse_args(argv, baton)
  16     if args:
  17         dir = args[0]
  18     else:
  19         dir = "."
  20     shell.drop_priviledges(dir, options.log_file)
  21     util.chdir(dir)
  22     sh = shell.Shell()
  23     util.set_git_env()
  24     use_shm = False # if you are running --continue, this is guaranteed to be False
  25     temp_dir = None
  26     try: # global try-finally for cleaning up /dev/shm if it's being used
  27         if options.continue_:
  28             temp_wc_dir = os.getcwd()
  29             wc = deploy.WorkingCopy(".")
  30             user_commit, next_commit = open(".git/WIZARD_PARENTS", "r").read().split()
  31             repo = open(".git/WIZARD_REPO", "r").read()
  32             version = open(".git/WIZARD_UPGRADE_VERSION", "r").read()
  33             if not options.log_file and os.path.exists(".git/WIZARD_LOG_FILE"):
  34                 options.log_file = open(".git/WIZARD_LOG_FILE", "r").read()
  35                 # reload logging
  36                 command.setup_file_logger(options.log_file, options.debug)
  37             logging.info("Continuing upgrade...")
  38             util.chdir(sh.eval("git", "config", "remote.origin.url"))
  39             d = deploy.ProductionCopy(".")
  40             try:
  41                 sh.call("git", "status")
  42                 raise LocalChangesError()
  43             except shell.CallError:
  44                 pass
  45         else:
  46             d = deploy.ProductionCopy(".")
  47             if os.path.exists(".scripts/blacklisted"):
  48                 reason = open(".scripts/blacklisted").read()
  49                 # ignore blank blacklisted files
  50                 if reason:
  51                     print reason
  52                     raise BlacklistedError(reason)
  53                 else:
  54                     logging.warning("Application was blacklisted, but no reason was found");
  55             d.verify()
  56             d.verifyTag(options.srv_path)
  57             d.verifyGit(options.srv_path)
  58             d.verifyConfigured()
  59             d.verifyVersion()
  60             if not options.dry_run:
  61                 d.verifyWeb()
  62             repo = d.application.repository(options.srv_path)
  63             version = calculate_newest_version(sh, repo)
  64             if version == d.app_version.scripts_tag and not options.force:
  65                 # don't log this error
  66                 # XXX: maybe we should build this in as a flag to add
  67                 # to exceptions w/ our exception handler
  68                 sys.stderr.write("Traceback:\n  (n/a)\nAlreadyUpgraded\n")
  69                 sys.exit(1)
  70             logging.info("Upgrading %s" % os.getcwd())
  71             kib_usage, kib_limit = scripts.get_quota_usage_and_limit()
  72             if kib_limit is not None and (kib_limit - kib_usage) < kib_buffer:
  73                 raise QuotaTooLow
  74             if not options.dry_run:
  75                 perform_pre_commit(sh)
  76             # If /dev/shm exists, it's a tmpfs and we can use it
  77             # to do a fast git merge. Don't forget to move it to
  78             # /tmp if it fails.
  79             if not options.dry_run:
  80                 use_shm = os.path.exists("/dev/shm")
  81             temp_dir, temp_wc_dir = perform_tmp_clone(sh, use_shm)
  82             with util.ChangeDirectory(temp_wc_dir):
  83                 wc = deploy.WorkingCopy(".")
  84                 sh.call("git", "remote", "add", "scripts", repo)
  85                 sh.call("git", "fetch", "-q", "scripts")
  86                 user_commit, next_commit = calculate_parents(sh, version)
  87                 # save variables so that --continue will work
  88                 # yeah yeah no trailing newline whatever
  89                 open(".git/WIZARD_REPO", "w").write(repo)
  90                 open(".git/WIZARD_UPGRADE_VERSION", "w").write(version)
  91                 open(".git/WIZARD_PARENTS", "w").write("%s\n%s" % (user_commit, next_commit))
  92                 open(".git/WIZARD_SIZE", "w").write(str(scripts.get_disk_usage()))
  93                 if options.log_file:
  94                     open(".git/WIZARD_LOG_FILE", "w").write(options.log_file)
  95                 perform_merge(sh, repo, d, wc, version, use_shm, kib_limit and kib_limit - kib_usage or None)
  96         # variables: version, user_commit, next_commit, temp_wc_dir
  97         with util.ChangeDirectory(temp_wc_dir):
  98             try:
  99                 sh.call("git", "status")
 100                 sh.call("git", "commit", "-m", "throw-away commit")
 101             except shell.CallError:
 102                 pass
 103             message = make_commit_message(version)
 104             new_tree = sh.eval("git", "rev-parse", "HEAD^{tree}")
 105             final_commit = sh.eval("git", "commit-tree", new_tree,
 106                     "-p", user_commit, "-p", next_commit, input=message, log=True)
 107             # a master branch may not necessarily exist if the user
 108             # was manually installed to an earlier version
 109             try:
 110                 sh.call("git", "checkout", "-q", "-b", "master", "--")
 111             except shell.CallError:
 112                 sh.call("git", "checkout", "-q", "master", "--")
 113             sh.call("git", "reset", "-q", "--hard", final_commit)
 114             # This is a quick sanity check to make sure we didn't completely
 115             # mess up the merge
 116             wc.invalidateCache()
 117             wc.verifyVersion()
 118         # Till now, all of our operations were in a tmp sandbox.
 119         if options.dry_run:
 120             logging.info("Dry run, bailing.  See results at %s" % temp_wc_dir)
 121             return
 122         # Ok, now we have to do a crazy complicated dance to see if we're
 123         # going to have enough quota to finish what we need
 124         pre_size = int(open(os.path.join(temp_wc_dir, ".git/WIZARD_SIZE"), "r").read())
 125         post_size = scripts.get_disk_usage(temp_wc_dir)
 126         kib_usage, kib_limit = scripts.get_quota_usage_and_limit()
 127         backup = d.backup(options)
 128         if kib_limit is not None and (kib_limit - kib_usage) - (post_size - pre_size) / 1024 < kib_buffer:
 129             shutil.rmtree(os.path.join(".scripts/backups", sh.eval("wizard", "restore").splitlines()[0]))
 130             raise QuotaTooLow
 131         # XXX: frob .htaccess to make site inaccessible
 132         with util.IgnoreKeyboardInterrupts():
 133             with util.LockDirectory(".scripts-upgrade-lock"):
 134                 # git merge (which performs a fast forward)
 135                 sh.call("git", "pull", "-q", temp_wc_dir, "master")
 136                 version_obj = distutils.version.LooseVersion(version.partition('-')[2])
 137                 try:
 138                     # run update script
 139                     d.upgrade(version_obj, options)
 140                     d.verifyWeb()
 141                 except app.UpgradeFailure:
 142                     logging.warning("Upgrade failed: rolling back")
 143                     perform_restore(d, backup)
 144                     raise
 145                 except deploy.WebVerificationError as e:
 146                     logging.warning("Web verification failed: rolling back")
 147                     perform_restore(d, backup)
 148                     raise app.UpgradeVerificationFailure()
 149         # XXX: frob .htaccess to make site accessible
 150         #       to do this, check if .htaccess changed, first.  Upgrade
 151         #       process might have frobbed it.  Don't be
 152         #       particularly worried if the segment disappeared
 153     finally:
 154         if use_shm and temp_dir and os.path.exists(temp_dir):
 155             shutil.rmtree(temp_dir)
 156
 157 def perform_restore(d, backup):
 158     # You don't want d.restore() because it doesn't perform
 159     # the file level backup
 160     shell.Shell().call("wizard", "restore", backup)
 161     try:
 162         d.verifyWeb()
 163     except deploy.WebVerificationError:
 164         logging.critical("Web verification failed after rollback")
 165
 166 def make_commit_message(version):
 167     message = "Upgraded autoinstall in %s to %s.\n\n%s" % (util.get_dir_owner(), version, util.get_git_footer())
 168     try:
 169         message += "\nUpgraded-by: " + util.get_operator_git()
 170     except util.NoOperatorInfo:
 171         pass
 172     return message
 173
 174 def calculate_newest_version(sh, repo):
 175     # XXX: put this in Application
 176     return sh.eval("git", "--git-dir="+repo, "describe", "--tags", "master")
 177
 178 def calculate_parents(sh, version):
 179     user_commit = sh.eval("git", "rev-parse", "HEAD")
 180     next_commit = sh.eval("git", "rev-parse", version)
 181     return user_commit, next_commit
 182
 183 def perform_pre_commit(sh):
 184     message = "Pre-commit of %s locker before autoinstall upgrade.\n\n%s" % (util.get_dir_owner(), util.get_git_footer())
 185     try:
 186         message += "\nPre-commit-by: " + util.get_operator_git()
 187     except util.NoOperatorInfo:
 188         pass
 189     try:
 190         sh.call("git", "commit", "-a", "-m", message)
 191     except shell.CallError:
 192         logging.info("No changes detected")
 193
 194 def perform_tmp_clone(sh, use_shm):
 195     if use_shm:
 196         dir = "/dev/shm/wizard"
 197         if not os.path.exists(dir):
 198             os.mkdir(dir)
 199             os.chmod(dir, 0o777)
 200     else:
 201         dir = None
 202     temp_dir = tempfile.mkdtemp(prefix="wizard", dir=dir)
 203     temp_wc_dir = os.path.join(temp_dir, "repo")
 204     logging.info("Using temporary directory: " + temp_wc_dir)
 205     sh.call("git", "clone", "-q", "--shared", ".", temp_wc_dir)
 206     return temp_dir, temp_wc_dir
 207
 208 def perform_merge(sh, repo, d, wc, version, use_shm, kib_avail):
 209     # Note: avail_quota == None means unlimited
 210     # naive merge algorithm:
 211     # sh.call("git", "merge", "-m", message, "scripts/master")
 212     # crazy merge algorithm:
 213     def make_virtual_commit(tag, parents = []):
 214         """WARNING: Changes state of Git repository"""
 215         sh.call("git", "checkout", "-q", tag, "--")
 216         wc.parametrize(d)
 217         for file in wc.application.parametrized_files:
 218             try:
 219                 sh.call("git", "add", "--", file)
 220             except shell.CallError:
 221                 pass
 222         virtual_tree = sh.eval("git", "write-tree", log=True)
 223         parent_args = itertools.chain(*(["-p", p] for p in parents))
 224         virtual_commit = sh.eval("git", "commit-tree", virtual_tree,
 225                 *parent_args, input="", log=True)
 226         sh.call("git", "reset", "--hard")
 227         return virtual_commit
 228     user_tree = sh.eval("git", "rev-parse", "HEAD^{tree}")
 229     base_virtual_commit = make_virtual_commit(wc.app_version.scripts_tag)
 230     next_virtual_commit = make_virtual_commit(version, [base_virtual_commit])
 231     user_virtual_commit = sh.eval("git", "commit-tree", user_tree,
 232             "-p", base_virtual_commit, input="", log=True)
 233     sh.call("git", "checkout", user_virtual_commit, "--")
 234     wc.prepareMerge()
 235     try:
 236         sh.call("git", "commit", "--amend", "-a", "-m", "amendment")
 237     except shell.CallError as e:
 238         pass
 239     try:
 240         sh.call("git", "merge", next_virtual_commit)
 241     except shell.CallError as e:
 242         conflicts = e.stdout.count("CONFLICT") # not perfect, if there is a file named CONFLICT
 243         logging.info("Merge failed with these messages:\n\n" + e.stderr)
 244         # Run the application's specific merge resolution algorithms
 245         # and see if we can salvage it
 246         curdir = os.getcwd()
 247         if wc.resolveConflicts():
 248             logging.info("Resolved conflicts with application specific knowledge")
 249             sh.call("git", "commit", "-a", "-m", "merge")
 250             return
 251         # XXX: Maybe should recalculate conflicts
 252         logging.info("Conflict info:\n" + sh.eval("git", "diff"))
 253         curdir = mv_shm_to_tmp(curdir, use_shm)
 254         print "%d %s" % (conflicts, curdir)
 255         raise MergeFailed
 256
 257 def mv_shm_to_tmp(curdir, use_shm):
 258     if not use_shm: return curdir
 259     # Keeping all of our autoinstalls in shared memory is
 260     # a recipe for disaster, so let's move them to slightly
 261     # less volatile storage (a temporary directory)
 262     os.chdir(tempfile.gettempdir())
 263     newdir = tempfile.mkdtemp(prefix="wizard")
 264     # shutil, not os; at least on Ubuntu os.move fails
 265     # with "[Errno 18] Invalid cross-device link"
 266     shutil.move(curdir, newdir)
 267     shutil.rmtree(os.path.dirname(curdir))
 268     curdir = os.path.join(newdir, "repo")
 269     return curdir
 270
 271 def parse_args(argv, baton):
 272     usage = """usage: %prog upgrade [ARGS] [DIR]
 273
 274 Upgrades an autoinstall to the latest version.  This involves
 275 updating files and running .scripts/update.  If the merge fails,
 276 this program will write the number of conflicts and the directory
 277 of the conflicted working tree to stdout, separated by a space."""
 278     parser = command.WizardOptionParser(usage)
 279     parser.add_option("--dry-run", dest="dry_run", action="store_true",
 280             default=False, help="Prints would would be run without changing anything")
 281     # notice trailing underscore
 282     parser.add_option("--continue", dest="continue_", action="store_true",
 283             default=False, help="Continues an upgrade that has had its merge manually "
 284             "resolved using the current working directory as the resolved copy.")
 285     parser.add_option("--force", dest="force", action="store_true",
 286             default=False, help="Force running upgrade even if it's already at latest version.")
 287     baton.push(parser, "srv_path")
 288     options, args = parser.parse_all(argv)
 289     if len(args) > 1:
 290         parser.error("too many arguments")
 291     return options, args
 292
 293 class Error(command.Error):
 294     """Base exception for all exceptions raised by upgrade"""
 295     pass
 296
 297 class QuotaTooLow(Error):
 298     def __str__(self):
 299         return """
 300
 301 ERROR: The locker quota was too low to complete the autoinstall
 302 upgrade.
 303 """
 304
 305 class AlreadyUpgraded(Error):
 306     def __str__(self):
 307         return """
 308
 309 ERROR: This autoinstall is already at the latest version."""
 310
 311 class MergeFailed(Error):
 312     def __str__(self):
 313         return """
 314
 315 ERROR: Merge failed.  Resolve the merge by cd'ing to the
 316 temporary directory, finding conflicted files with `git status`,
 317 resolving the files, adding them using `git add` and then
 318 running `wizard upgrade --continue`."""
 319
 320 class LocalChangesError(Error):
 321     def __str__(self):
 322         return """
 323
 324 ERROR: Local changes occurred in the install while the merge was
 325 being processed so that a pull would not result in a fast-forward.
 326 The best way to resolve this is probably to attempt an upgrade again,
 327 with git rerere to remember merge resolutions (XXX: not sure if
 328 this actually works)."""
 329
 330 class BlacklistedError(Error):
 331     #: Reason why the autoinstall was blacklisted
 332     reason = None
 333     exitcode = errno_blacklisted
 334     def __init__(self, reason):
 335         self.reason = reason
 336     def __str__(self):
 337         return """
 338
 339 ERROR: This autoinstall was manually blacklisted against errors;
 340 if the user has not been notified of this, please send them
 341 mail.
 342
 343 The reason was: %s""" % self.reason