wizard/command/upgrade.py

   1 import optparse
   2 import sys
   3 import os
   4 import shutil
   5 import logging.handlers
   6 import errno
   7 import tempfile
   8 import itertools
   9
  10 from wizard import command, deploy, shell, util
  11
  12 def main(argv, baton):
  13     options, args = parse_args(argv, baton)
  14     if args:
  15         dir = args[0]
  16     else:
  17         dir = "."
  18     shell.drop_priviledges(dir, options.log_file)
  19     util.chdir(dir)
  20     sh = shell.Shell()
  21     util.set_git_env()
  22     if options.continue_:
  23         temp_wc_dir = os.getcwd()
  24         user_commit, next_commit = open(".git/WIZARD_PARENTS", "r").read().split()
  25         repo = open(".git/WIZARD_REPO", "r").read()
  26         version = open(".git/WIZARD_UPGRADE_VERSION", "r").read()
  27         util.chdir(sh.eval("git", "config", "remote.origin.url"))
  28         d = deploy.Deployment(".")
  29         try:
  30             sh.call("git", "status")
  31             raise LocalChangesError()
  32         except shell.CallError:
  33             pass
  34     else:
  35         d = deploy.Deployment(".")
  36         d.verify()
  37         d.verifyTag(options.srv_path)
  38         d.verifyGit(options.srv_path)
  39         d.verifyConfigured()
  40         d.verifyVersion()
  41         repo = d.application.repository(options.srv_path)
  42         version = calculate_newest_version(sh, repo)
  43         if version == d.app_version.scripts_tag:
  44             raise AlreadyUpgraded
  45         if not options.dry_run:
  46             perform_pre_commit(sh)
  47         temp_wc_dir = perform_tmp_clone(sh)
  48         with util.ChangeDirectory(temp_wc_dir):
  49             sh.call("git", "remote", "add", "scripts", repo)
  50             sh.call("git", "fetch", "scripts")
  51             user_commit, next_commit = calculate_parents(sh, version)
  52             # save variables so that --continue will work
  53             # yeah yeah no trailing newline whatever
  54             open(".git/WIZARD_REPO", "w").write(repo)
  55             open(".git/WIZARD_UPGRADE_VERSION", "w").write(version)
  56             open(".git/WIZARD_PARENTS", "w").write("%s\n%s" % (user_commit, next_commit))
  57             perform_merge(sh, repo, d, version)
  58     # variables: version, user_commit, next_commit, temp_wc_dir
  59     with util.ChangeDirectory(temp_wc_dir):
  60         message = make_commit_message(version)
  61         new_tree = sh.eval("git", "rev-parse", "HEAD^{tree}")
  62         final_commit = sh.eval("git", "commit-tree", new_tree,
  63                 "-p", user_commit, "-p", next_commit, input=message, log=True)
  64         # a master branch may not necessarily exist if the user
  65         # was manually installed to an earlier version
  66         try:
  67             sh.call("git", "checkout", "-b", "master", "--")
  68         except shell.CallError:
  69             sh.call("git", "checkout", "master", "--")
  70         sh.call("git", "reset", "--hard", final_commit)
  71     # Till now, all of our operations were in a tmp sandbox.
  72     if options.dry_run:
  73         logging.info("Dry run, bailing.  See results at %s" % temp_wc_dir)
  74         return
  75     # XXX: frob .htaccess to make site inaccessible
  76     # XXX: need locking
  77     # git merge (which performs a fast forward)
  78     #   - merge could fail (race); that's /really/ dangerous.
  79     sh.call("git", "pull", temp_wc_dir, "master")
  80     # run update script
  81     d.application.upgrade(options)
  82     # XXX: frob .htaccess to make site accessible
  83     # XXX:  - check if .htaccess changed, first.  Upgrade
  84     #       process might have frobbed it.  Don't be
  85     #       particularly worried if the segment dissappeared
  86
  87 def make_commit_message(version):
  88     message = "Upgraded autoinstall in %s to %s.\n\n%s" % (util.get_dir_owner(), version, util.get_git_footer())
  89     try:
  90         message += "\nUpgraded-by: " + util.get_operator_git()
  91     except util.NoOperatorInfo:
  92         pass
  93     return message
  94
  95 def calculate_newest_version(sh, repo):
  96     # XXX: put this in Application
  97     return sh.eval("git", "--git-dir="+repo, "describe", "--tags", "master")
  98
  99 def calculate_parents(sh, version):
 100     user_commit = sh.eval("git", "rev-parse", "HEAD")
 101     next_commit = sh.eval("git", "rev-parse", version)
 102     return user_commit, next_commit
 103
 104 def perform_pre_commit(sh):
 105     message = "Pre-commit of %s locker before autoinstall upgrade.\n\n%s" % (util.get_dir_owner(), util.get_git_footer())
 106     try:
 107         message += "\nPre-commit-by: " + util.get_operator_git()
 108     except util.NoOperatorInfo:
 109         pass
 110     try:
 111         sh.call("git", "commit", "-a", "-m", message)
 112     except shell.CallError:
 113         logging.info("No changes detected")
 114
 115 def perform_tmp_clone(sh):
 116     temp_dir = tempfile.mkdtemp(prefix="wizard")
 117     temp_wc_dir = os.path.join(temp_dir, "repo")
 118     logging.info("Using temporary directory: " + temp_wc_dir)
 119     sh.call("git", "clone", "--shared", ".", temp_wc_dir)
 120     return temp_wc_dir
 121
 122 def perform_merge(sh, repo, d, version):
 123     # naive merge algorithm:
 124     # sh.call("git", "merge", "-m", message, "scripts/master")
 125     # crazy merge algorithm:
 126     def make_virtual_commit(tag, parents = []):
 127         """WARNING: Changes state of Git repository"""
 128         sh.call("git", "checkout", tag, "--")
 129         d.parametrize(".")
 130         for file in d.application.parametrized_files:
 131             try:
 132                 sh.call("git", "add", "--", file)
 133             except shell.CallError:
 134                 pass
 135         virtual_tree = sh.eval("git", "write-tree", log=True)
 136         parent_args = itertools.chain(*(["-p", p] for p in parents))
 137         virtual_commit = sh.eval("git", "commit-tree", virtual_tree,
 138                 *parent_args, input="", log=True)
 139         sh.call("git", "reset", "--hard")
 140         return virtual_commit
 141     user_tree = sh.eval("git", "rev-parse", "HEAD^{tree}")
 142     base_virtual_commit = make_virtual_commit(d.app_version.scripts_tag)
 143     next_virtual_commit = make_virtual_commit(version, [base_virtual_commit])
 144     user_virtual_commit = sh.eval("git", "commit-tree", user_tree,
 145             "-p", base_virtual_commit, input="", log=True)
 146     sh.call("git", "checkout", user_virtual_commit, "--")
 147     try:
 148         sh.call("git", "merge", next_virtual_commit)
 149     except shell.CallError:
 150         print os.getcwd()
 151         logging.info("Conflict info:\n", sh.eval("git", "diff"))
 152         raise MergeFailed
 153
 154 def parse_args(argv, baton):
 155     usage = """usage: %prog upgrade [ARGS] [DIR]
 156
 157 Upgrades an autoinstall to the latest version.  This involves
 158 updating files and running .scripts/update.
 159
 160 WARNING: This is still experimental."""
 161     parser = command.WizardOptionParser(usage)
 162     parser.add_option("--dry-run", dest="dry_run", action="store_true",
 163             default=False, help="Prints would would be run without changing anything")
 164     # notice trailing underscore
 165     parser.add_option("--continue", dest="continue_", action="store_true",
 166             default=False, help="Continues an upgrade that has had its merge manually "
 167             "resolved using the current working directory as the resolved copy.")
 168     baton.push(parser, "srv_path")
 169     options, args = parser.parse_all(argv)
 170     if len(args) > 1:
 171         parser.error("too many arguments")
 172     return options, args
 173
 174 class Error(command.Error):
 175     """Base exception for all exceptions raised by upgrade"""
 176     pass
 177
 178 class AlreadyUpgraded(Error):
 179     def __str__(self):
 180         return """
 181
 182 ERROR: This autoinstall is already at the latest version."""
 183
 184 class MergeFailed(Error):
 185     def __str__(self):
 186         return """
 187
 188 ERROR: Merge failed.  Resolve the merge by cd'ing to the
 189 temporary directory, finding conflicted files with `git status`,
 190 resolving the files, adding them using `git add`, and then
 191 committing your changes with `git commit` (your log message
 192 will be ignored), and then running `wizard upgrade --continue`."""
 193
 194 class LocalChangesError(Error):
 195     def __str__(self):
 196         return """
 197
 198 ERROR: Local changes occurred in the install while the merge was
 199 being processed so that a pull would not result in a fast-forward.
 200 The best way to resolve this is probably to attempt an upgrade again,
 201 with git rerere to remember merge resolutions (XXX: not sure if
 202 this actually works)."""
 203