lib/wlrepo/backend_mercurial.py

   1 # -*- encoding: utf-8 -*-
   2
   3 __author__ = "Łukasz Rekucki"
   4 __date__ = "$2009-09-18 10:49:24$"
   5
   6 __doc__ = """RAL implementation over Mercurial"""
   7
   8 import mercurial
   9 from mercurial import localrepo as hglrepo
  10 from mercurial import ui as hgui
  11 from mercurial.node import hex as to_hex
  12 import re
  13 import wlrepo
  14
  15 FILTER = re.compile(r"^pub_(.+)\.xml$", re.UNICODE)
  16
  17 def default_filter(name):
  18     m = FILTER.match(name)
  19     if m is not None:
  20         return name, m.group(1)
  21     return None
  22
  23 class MercurialLibrary(wlrepo.Library):
  24
  25     def __init__(self, path, maincabinet="default", ** kwargs):
  26         super(wlrepo.Library, self).__init__( ** kwargs)
  27
  28         self._hgui = hgui.ui()
  29         self._hgui.config('ui', 'quiet', 'true')
  30         self._hgui.config('ui', 'interactive', 'false')
  31
  32         import os.path
  33         self._ospath = self._sanitize_string(os.path.realpath(path))
  34
  35         maincabinet = self._sanitize_string(maincabinet)
  36
  37         if os.path.isdir(path):
  38             try:
  39                 self._hgrepo = hglrepo.localrepository(self._hgui, path)
  40             except mercurial.error.RepoError:
  41                 raise wlrepo.LibraryException("[HGLibrary] Not a valid repository at path '%s'." % path)
  42         elif kwargs.get('create', False):
  43             os.makedirs(path)
  44             try:
  45                 self._hgrepo = hglrepo.localrepository(self._hgui, path, create=1)
  46             except mercurial.error.RepoError:
  47                 raise wlrepo.LibraryException("[HGLibrary] Can't create a repository on path '%s'." % path)
  48         else:
  49             raise wlrepo.LibraryException("[HGLibrary] Can't open a library on path '%s'." % path)
  50
  51         # fetch the main cabinet
  52         lock = self._hgrepo.lock()
  53         try:
  54             btags = self._hgrepo.branchtags()
  55
  56             if not self._has_branch(maincabinet):
  57                 raise wlrepo.LibraryException("[HGLibrary] No branch named '%s' to init main cabinet" % maincabinet)
  58
  59             self._maincab = MercurialCabinet(self, maincabinet)
  60         finally:
  61             lock.release()
  62
  63     @property
  64     def main_cabinet(self):
  65         return self._maincab
  66
  67     def document(self, docid, user):
  68         return self.cabinet(docid, user, create=False).retrieve()
  69
  70     def cabinet(self, docid, user, create=False):
  71         bname = self._bname(user, docid)
  72
  73         lock = self._lock(True)
  74         try:
  75             if self._has_branch(bname):
  76                 return MercurialCabinet(self, bname, doc=docid, user=user)
  77
  78             if not create:
  79                 raise wlrepo.CabinetNotFound(bname)
  80
  81             # check if the docid exists in the main cabinet
  82             needs_touch = not self._maincab.exists(docid)
  83             cab = MercurialCabinet(self, bname, doc=docid, user=user)
  84
  85             name, fileid = cab._filename(None)
  86
  87             def cleanup_action(l):
  88                 if needs_touch:
  89                     l._fileopener()(fileid, "w").write('')
  90                     l._fileadd(fileid)
  91
  92                 garbage = [fid for (fid, did) in l._filelist() if not did.startswith(docid)]
  93                 l._filesrm(garbage)
  94
  95             # create the branch
  96             self._create_branch(bname, before_commit=cleanup_action)
  97             return MercurialCabinet(self, bname, doc=docid, user=user)
  98         finally:
  99             lock.release()
 100
 101     #
 102     # Private methods
 103     #
 104
 105     #
 106     # Locking
 107     #
 108
 109     def _lock(self, write_mode=False):
 110         return self._hgrepo.wlock() # no support for read/write mode yet
 111
 112     def _transaction(self, write_mode, action):
 113         lock = self._lock(write_mode)
 114         try:
 115             return action(self)
 116         finally:
 117             lock.release()
 118
 119     #
 120     # Basic repo manipulation
 121     #
 122
 123     def _checkout(self, rev, force=True):
 124         return MergeStatus(mercurial.merge.update(self._hgrepo, rev, False, force, None))
 125
 126     def _merge(self, rev):
 127         """ Merge the revision into current working directory """
 128         return MergeStatus(mercurial.merge.update(self._hgrepo, rev, True, False, None))
 129
 130     def _common_ancestor(self, revA, revB):
 131         return self._hgrepo[revA].ancestor(self.repo[revB])
 132
 133     def _commit(self, message, user=u"library"):
 134         return self._hgrepo.commit(text=message, user=user)
 135
 136
 137     def _fileexists(self, fileid):
 138         return (fileid in self._hgrepo[None])
 139
 140     def _fileadd(self, fileid):
 141         return self._hgrepo.add([fileid])
 142
 143     def _filesadd(self, fileid_list):
 144         return self._hgrepo.add(fileid_list)
 145
 146     def _filerm(self, fileid):
 147         return self._hgrepo.remove([fileid])
 148
 149     def _filesrm(self, fileid_list):
 150         return self._hgrepo.remove(fileid_list)
 151
 152     def _filelist(self, filter=default_filter):
 153         for name in  self._hgrepo[None]:
 154             result = filter(name)
 155             if result is None: continue
 156
 157             yield result
 158
 159     def _fileopener(self):
 160         return self._hgrepo.wopener
 161
 162     def _filectx(self, fileid, branchid):
 163         return self._hgrepo.filectx(fileid, changeid=branchid)
 164
 165     #
 166     # BASIC BRANCH routines
 167     #
 168
 169     def _bname(self, user, docid):
 170         """Returns a branch name for a given document and user."""
 171         docid = self._sanitize_string(docid)
 172         uname = self._sanitize_string(user)
 173         return "personal_" + uname + "_file_" + docid;
 174
 175     def _has_branch(self, name):
 176         return self._hgrepo.branchmap().has_key(self._sanitize_string(name))
 177
 178     def _branch_tip(self, name):
 179         name = self._sanitize_string(name)
 180         return self._hgrepo.branchtags()[name]
 181
 182     def _create_branch(self, name, parent=None, before_commit=None):
 183         name = self._sanitize_string(name)
 184
 185         if self._has_branch(name): return # just exit
 186
 187         if parent is None:
 188             parent = self._maincab
 189
 190         parentrev = parent._hgtip()
 191
 192         self._checkout(parentrev)
 193         self._hgrepo.dirstate.setbranch(name)
 194
 195         if before_commit: before_commit(self)
 196
 197         self._commit("[AUTO] Initial commit for branch '%s'." % name, user='library')
 198
 199         # revert back to main
 200         self._checkout(self._maincab._hgtip())
 201         return self._branch_tip(name)
 202
 203     def _switch_to_branch(self, branchname):
 204         current = self._hgrepo[None].branch()
 205
 206         if current == branchname:
 207             return current # quick exit
 208
 209         self._checkout(self._branch_tip(branchname))
 210         return branchname
 211
 212     #
 213     # Merges
 214     #
 215
 216
 217
 218     #
 219     # Utils
 220     #
 221
 222     @staticmethod
 223     def _sanitize_string(s):
 224         if isinstance(s, unicode):
 225             s = s.encode('utf-8')
 226         return s
 227
 228 class MercurialCabinet(wlrepo.Cabinet):
 229
 230     def __init__(self, library, branchname, doc=None, user=None):
 231         if doc and user:
 232             super(MercurialCabinet, self).__init__(library, doc=doc, user=user)
 233         else:
 234             super(MercurialCabinet, self).__init__(library, name=branchname)
 235
 236         self._branchname = branchname
 237
 238     def shelf(self, selector=None):
 239         if selector is not None:
 240             raise NotImplementedException()
 241
 242         return MercurialShelf(self, self._hgtip())
 243
 244     def documents(self):
 245         return self._execute_in_branch(action=lambda l, c: (e[1] for e in l._filelist()))
 246
 247     def retrieve(self, part=None, shelf=None):
 248         name, fileid = self._filename(part)
 249
 250         if fileid is None:
 251             raise wlrepo.LibraryException("Can't retrieve main document from main cabinet.")
 252
 253         return self._execute_in_branch(lambda l, c: MercurialDocument(c, name, fileid))
 254
 255     def create(self, name, initial_data):
 256         name, fileid = self._filename(name)
 257
 258         if name is None:
 259             raise ValueError("Can't create main doc for maincabinet.")
 260
 261         def create_action(l, c):
 262             if l._fileexists(fileid):
 263                 raise wlrepo.LibraryException("Can't create document '%s' in cabinet '%s' - it already exists" % (fileid, c.name))
 264
 265             fd = l._fileopener()(fileid, "w")
 266             fd.write(initial_data)
 267             fd.close()
 268             l._fileadd(fileid)
 269             l._commit("File '%s' created." % fileid)
 270             return MercurialDocument(c, fileid=fileid, name=name)
 271
 272         return self._execute_in_branch(create_action)
 273
 274     def exists(self, part=None, shelf=None):
 275         name, filepath = self._filename(part)
 276
 277         if filepath is None: return False
 278         return self._execute_in_branch(lambda l, c: l._fileexists(filepath))
 279
 280     def _execute_in_branch(self, action, write=False):
 281         def switch_action(library):
 282             old = library._switch_to_branch(self._branchname)
 283             try:
 284                 return action(library, self)
 285             finally:
 286                 library._switch_to_branch(old)
 287
 288         return self._library._transaction(write_mode=write, action=switch_action)
 289
 290     def _filename(self, part):
 291         part = self._library._sanitize_string(part)
 292         fileid = None
 293
 294         if self._maindoc == '':
 295             if part is None: return [None, None]
 296             fileid = part
 297         else:
 298             fileid = self._maindoc + (('$' + part) if part else '')
 299
 300         return fileid, 'pub_' + fileid + '.xml'
 301
 302     def _fileopener(self):
 303         return self._library._fileopener()
 304
 305     def _hgtip(self):
 306         return self._library._branch_tip(self._branchname)
 307
 308     def _filectx(self, fileid):
 309         return self._library._filectx(fileid, self._branchname)
 310
 311 class MercurialDocument(wlrepo.Document):
 312
 313     def __init__(self, cabinet, name, fileid):
 314         super(MercurialDocument, self).__init__(cabinet, name=name)
 315         self._opener = self._cabinet._fileopener()
 316         self._fileid = fileid
 317         self._refresh()
 318
 319     def _refresh(self):
 320         self._filectx = self._cabinet._filectx(self._fileid)
 321         self._shelf = MercurialShelf(self, self._filectx.node())
 322
 323     def read(self):
 324         return self._opener(self._filectx.path(), "r").read()
 325
 326     def write(self, data):
 327         return self._opener(self._filectx.path(), "w").write(data)
 328
 329     def commit(self, message, user):
 330         self.library._fileadd(self._fileid)
 331         self.library._commit(self._fileid, message, user)
 332
 333     def update(self):
 334         if self._cabinet.is_main():
 335             return True # always up-to-date
 336
 337         mdoc = self.library.document(self._fileid)
 338
 339         mshelf = mdoc.shelf()
 340         shelf = self.shelf()
 341
 342         if not mshelf.ancestorof(shelf) and not shelf.parentof(mshelf):
 343             shelf.merge_with(mshelf)
 344
 345         return rc.ALL_OK
 346
 347     def share(self, message, user):
 348         if self._cabinet.is_main():
 349             return True # always shared
 350
 351         main = self.shared_version()
 352         local = self.shelf()
 353
 354         no_changes = True
 355
 356         # Case 1:
 357         #         * local
 358         #         |
 359         #         * <- can also be here!
 360         #        /|
 361         #       / |
 362         # main *  *
 363         #      |  |
 364         # The local branch has been recently updated,
 365         # so we don't need to update yet again, but we need to
 366         # merge down to default branch, even if there was
 367         # no commit's since last update
 368
 369         if main.ancestorof(local):
 370             main.merge_with(local, user=user, message=message)
 371             no_changes = False
 372
 373         # Case 2:
 374         #
 375         # main *  * local
 376         #      |\ |
 377         #      | \|
 378         #      |  *
 379         #      |  |
 380         #
 381         # Default has no changes, to update from this branch
 382         # since the last merge of local to default.
 383         elif main.has_common_ancestor(local):
 384             if not local.parentof(main):
 385                 main.merge_with(local, user=user, message=message)
 386                 no_changes = False
 387
 388         # Case 3:
 389         # main *
 390         #      |
 391         #      * <- this case overlaps with previos one
 392         #      |\
 393         #      | \
 394         #      |  * local
 395         #      |  |
 396         #
 397         # There was a recent merge to the defaul branch and
 398         # no changes to local branch recently.
 399         #
 400         # Use the fact, that user is prepared to see changes, to
 401         # update his branch if there are any
 402         elif local.ancestorof(main):
 403             if not local.parentof(main):
 404                 local.merge_with(main, user=user, message='Local branch update.')
 405                 no_changes = False
 406         else:
 407             local.merge_with(main, user=user, message='Local branch update.')
 408
 409             self._refresh()
 410             local = self.shelf()
 411
 412             main.merge_with(local, user=user, message=message)
 413
 414     def shared(self):
 415         return self.library.document(self._fileid)
 416
 417     @property
 418     def size(self):
 419         return self._filectx.size()
 420
 421
 422     def shelf(self):
 423         return self._shelf
 424
 425     @property
 426     def last_modified(self):
 427         return self._filectx.date()
 428
 429     def __str__(self):
 430         return u"Document(%s->%s)" % (self._cabinet.name, self._name)
 431
 432
 433 class MercurialShelf(wlrepo.Shelf):
 434
 435     def __init__(self, cabinet, revision):
 436         super(MercurialShelf, self).__init__(cabinet)
 437         self._revision = revision
 438
 439     @property
 440     def _rev(self):
 441         return _revision
 442
 443     def __str__(self):
 444         return to_hex(self._revision)
 445
 446
 447 class MergeStatus(object):
 448     def __init__(self, mstatus):
 449         self.updated = mstatus[0]
 450         self.merged = mstatus[1]
 451         self.removed = mstatus[2]
 452         self.unresolved = mstatus[3]
 453
 454     def isclean(self):
 455         return self.unresolved == 0
 456
 457 class UpdateStatus(object):
 458
 459     def __init__(self, mstatus):
 460         self.modified = mstatus[0]
 461         self.added = mstatus[1]
 462         self.removed = mstatus[2]
 463         self.deleted = mstatus[3]
 464         self.untracked = mstatus[4]
 465         self.ignored = mstatus[5]
 466         self.clean = mstatus[6]
 467
 468     def has_changes(self):
 469         return bool(len(self.modified) + len(self.added) + \
 470                     len(self.removed) + len(self.deleted))
 471
 472 __all__ = ["MercurialLibrary"]