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 nullid
  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, 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, 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, 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     def _changectx(self, nodeid):
 166         return self._hgrepo.changectx(nodeid)
 167
 168     #
 169     # BASIC BRANCH routines
 170     #
 171
 172     def _bname(self, user, docid):
 173         """Returns a branch name for a given document and user."""
 174         docid = self._sanitize_string(docid)
 175         uname = self._sanitize_string(user)
 176         return "personal_" + uname + "_file_" + docid;
 177
 178     def _has_branch(self, name):
 179         return self._hgrepo.branchmap().has_key(self._sanitize_string(name))
 180
 181     def _branch_tip(self, name):
 182         name = self._sanitize_string(name)
 183         return self._hgrepo.branchtags()[name]
 184
 185     def _create_branch(self, name, parent=None, before_commit=None):
 186         name = self._sanitize_string(name)
 187
 188         if self._has_branch(name): return # just exit
 189
 190         if parent is None:
 191             parent = self._maincab
 192
 193         parentrev = parent._hgtip()
 194
 195         self._checkout(parentrev)
 196         self._hgrepo.dirstate.setbranch(name)
 197
 198         if before_commit: before_commit(self)
 199
 200         self._commit("[AUTO] Initial commit for branch '%s'." % name, user='library')
 201
 202         # revert back to main
 203         self._checkout(self._maincab._hgtip())
 204         return self._branch_tip(name)
 205
 206     def _switch_to_branch(self, branchname):
 207         current = self._hgrepo[None].branch()
 208
 209         if current == branchname:
 210             return current # quick exit
 211
 212         self._checkout(self._branch_tip(branchname))
 213         return branchname
 214
 215     def shelf(self, nodeid):
 216         return MercurialShelf(self, self._changectx(nodeid))
 217
 218
 219     #
 220     # Utils
 221     #
 222
 223     @staticmethod
 224     def _sanitize_string(s):
 225         if isinstance(s, unicode):
 226             s = s.encode('utf-8')
 227         return s
 228
 229 class MercurialCabinet(wlrepo.Cabinet):
 230
 231     def __init__(self, library, branchname=None, doc=None, user=None):
 232         if doc and user:
 233             super(MercurialCabinet, self).__init__(library, doc=doc, user=user)
 234             self._branchname = library._bname(user=user, docid=doc)
 235         elif branchname:
 236             super(MercurialCabinet, self).__init__(library, name=branchname)
 237             self._branchname = branchname
 238         else:
 239             raise ValueError("Provide either doc/user or branchname")
 240
 241     def shelf(self, selector=None):
 242         return self._library.shelf(self._branchname)
 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         print "Retrieving document %s from cab %s" % (name, self._name)
 251
 252         if fileid is None:
 253             raise wlrepo.LibraryException("Can't retrieve main document from main cabinet.")
 254
 255         def retrieve_action(l,c):
 256             if l._fileexists(fileid):
 257                 return MercurialDocument(c, name=name, fileid=fileid)
 258             return None
 259
 260         return self._execute_in_branch(retrieve_action)
 261
 262     def create(self, name, initial_data):
 263         name, fileid = self._filename(name)
 264
 265         if name is None:
 266             raise ValueError("Can't create main doc for maincabinet.")
 267
 268         def create_action(l, c):
 269             if l._fileexists(fileid):
 270                 raise wlrepo.LibraryException("Can't create document '%s' in cabinet '%s' - it already exists" % (fileid, c.name))
 271
 272             fd = l._fileopener()(fileid, "w")
 273             fd.write(initial_data)
 274             fd.close()
 275             l._fileadd(fileid)
 276             l._commit("File '%s' created." % fileid)
 277             return MercurialDocument(c, fileid=fileid, name=name)
 278
 279         return self._execute_in_branch(create_action)
 280
 281     def exists(self, part=None, shelf=None):
 282         name, filepath = self._filename(part)
 283
 284         if filepath is None: return False
 285         return self._execute_in_branch(lambda l, c: l._fileexists(filepath))
 286
 287     def _execute_in_branch(self, action, write=False):
 288         def switch_action(library):
 289             old = library._switch_to_branch(self._branchname)
 290             try:
 291                 return action(library, self)
 292             finally:
 293                 library._switch_to_branch(old)
 294
 295         return self._library._transaction(write_mode=write, action=switch_action)
 296
 297     def _filename(self, part):
 298         part = self._library._sanitize_string(part)
 299         docid = None
 300
 301         if self._maindoc == '':
 302             if part is None: rreeturn [None, None]
 303             docid = part
 304         else:
 305             docid = self._maindoc + (('$' + part) if part else '')
 306
 307         return docid, 'pub_' + docid + '.xml'
 308
 309     def _fileopener(self):
 310         return self._library._fileopener()
 311
 312     def _hgtip(self):
 313         return self._library._branch_tip(self._branchname)
 314
 315     def _filectx(self, fileid):
 316         return self._library._filectx(fileid, self._branchname)
 317
 318     def ismain(self):
 319         return (self._library.main_cabinet == self)
 320
 321 class MercurialDocument(wlrepo.Document):
 322
 323     def __init__(self, cabinet, name, fileid):
 324         super(MercurialDocument, self).__init__(cabinet, name=name)
 325         self._opener = self._cabinet._fileopener()
 326         self._fileid = fileid
 327         self.refresh()
 328
 329     def refresh(self):
 330         self._filectx = self._cabinet._filectx(self._fileid)
 331
 332     def read(self):
 333         return self._opener(self._filectx.path(), "r").read()
 334
 335     def write(self, data):
 336         return self._opener(self._filectx.path(), "w").write(data)
 337
 338     def commit(self, message, user):
 339         self.library._fileadd(self._fileid)
 340         self.library._commit(self._fileid, message, user)
 341
 342     def update(self):
 343         lock = self.library._lock()
 344         try:
 345             if self._cabinet.ismain():
 346                 return True # always up-to-date
 347
 348             user = self._cabinet.username or 'library'
 349             mdoc = self.library.document(self._fileid)
 350
 351             mshelf = mdoc.shelf()
 352             shelf = self.shelf()
 353
 354             if not mshelf.ancestorof(shelf) and not shelf.parentof(mshelf):
 355                 shelf.merge_with(mshelf, user=user)
 356
 357             return True
 358         finally:
 359             lock.release()
 360
 361     def share(self, message):
 362         lock = self.library._lock()
 363         try:
 364             print "sharing from", self._cabinet, self._cabinet.username
 365
 366             if self._cabinet.ismain():
 367                 return True # always shared
 368
 369             if self._cabinet.username is None:
 370                 raise ValueError("Can only share documents from personal cabinets.")
 371
 372             user = self._cabinet.username
 373
 374             main = self.shared().shelf()
 375             local = self.shelf()
 376
 377             no_changes = True
 378
 379             # Case 1:
 380             #         * local
 381             #         |
 382             #         * <- can also be here!
 383             #        /|
 384             #       / |
 385             # main *  *
 386             #      |  |
 387             # The local branch has been recently updated,
 388             # so we don't need to update yet again, but we need to
 389             # merge down to default branch, even if there was
 390             # no commit's since last update
 391
 392             if main.ancestorof(local):
 393                 main.merge_with(local, user=user, message=message)
 394                 no_changes = False
 395
 396             # Case 2:
 397             #
 398             # main *  * local
 399             #      |\ |
 400             #      | \|
 401             #      |  *
 402             #      |  |
 403             #
 404             # Default has no changes, to update from this branch
 405             # since the last merge of local to default.
 406             elif local.has_common_ancestor(main):
 407                 if not local.parentof(main):
 408                     main.merge_with(local, user=user, message=message)
 409                     no_changes = False
 410
 411             # Case 3:
 412             # main *
 413             #      |
 414             #      * <- this case overlaps with previos one
 415             #      |\
 416             #      | \
 417             #      |  * local
 418             #      |  |
 419             #
 420             # There was a recent merge to the defaul branch and
 421             # no changes to local branch recently.
 422             #
 423             # Use the fact, that user is prepared to see changes, to
 424             # update his branch if there are any
 425             elif local.ancestorof(main):
 426                 if not local.parentof(main):
 427                     local.merge_with(main, user=user, message='Local branch update.')
 428                     no_changes = False
 429             else:
 430                 local.merge_with(main, user=user, message='Local branch update.')
 431
 432                 self._refresh()
 433                 local = self.shelf()
 434
 435                 main.merge_with(local, user=user, message=message)
 436         finally:
 437             lock.release()
 438
 439     def shared(self):
 440         return self.library.main_cabinet.retrieve(self._name)
 441
 442     def exists(self):
 443         return self._cabinet.exists(self._fileid)
 444
 445     @property
 446     def size(self):
 447         return self._filectx.size()
 448
 449     def shelf(self):
 450         return MercurialShelf(self.library, self._filectx.node())
 451
 452     @property
 453     def last_modified(self):
 454         return self._filectx.date()
 455
 456     def __str__(self):
 457         return u"Document(%s->%s)" % (self._cabinet.name, self._name)
 458
 459     def __eq__(self, other):
 460         return self._filectx == other._filectx
 461
 462
 463
 464 class MercurialShelf(wlrepo.Shelf):
 465
 466     def __init__(self, lib, changectx):
 467         super(MercurialShelf, self).__init__(lib)
 468
 469         if isinstance(changectx, str):
 470             self._changectx = lib._changectx(changectx)
 471         else:
 472             self._changectx = changectx
 473
 474     @property
 475     def _rev(self):
 476         return self._changectx.node()
 477
 478     def __str__(self):
 479         return self._changectx.hex()
 480
 481     def __repr__(self):
 482         return "MercurialShelf(%s)" % self._changectx.hex()
 483
 484     def ancestorof(self, other):
 485         nodes = list(other._changectx._parents)
 486         while nodes[0].node() != nullid:
 487             v = nodes.pop(0)
 488             if v == self._changectx:
 489                 return True
 490             nodes.extend( v._parents )
 491         return False
 492
 493     def parentof(self, other):
 494         return self._changectx in other._changectx._parents
 495
 496     def has_common_ancestor(self, other):
 497         a = self._changectx.ancestor(other._changectx)
 498         print a, self._changectx.branch(), a.branch()
 499
 500         return (a.branch() == self._changectx.branch())
 501
 502     def merge_with(self, other, user, message):
 503         lock = self._library._lock(True)
 504         try:
 505             self._library._checkout(self._changectx.node())
 506             self._library._merge(other._changectx.node())
 507         finally:
 508             lock.release()
 509
 510     def __eq__(self, other):
 511         return self._changectx.node() == other._changectx.node()
 512
 513
 514 class MergeStatus(object):
 515     def __init__(self, mstatus):
 516         self.updated = mstatus[0]
 517         self.merged = mstatus[1]
 518         self.removed = mstatus[2]
 519         self.unresolved = mstatus[3]
 520
 521     def isclean(self):
 522         return self.unresolved == 0
 523
 524 class UpdateStatus(object):
 525
 526     def __init__(self, mstatus):
 527         self.modified = mstatus[0]
 528         self.added = mstatus[1]
 529         self.removed = mstatus[2]
 530         self.deleted = mstatus[3]
 531         self.untracked = mstatus[4]
 532         self.ignored = mstatus[5]
 533         self.clean = mstatus[6]
 534
 535     def has_changes(self):
 536         return bool(len(self.modified) + len(self.added) + \
 537                     len(self.removed) + len(self.deleted))
 538
 539 __all__ = ["MercurialLibrary"]