services/fuse/arvados_fuse/fusedir.py

   1 # Copyright (C) The Arvados Authors. All rights reserved.
   2 #
   3 # SPDX-License-Identifier: AGPL-3.0
   4
   5 import logging
   6 import re
   7 import time
   8 import llfuse
   9 import arvados
  10 import apiclient
  11 import functools
  12 import threading
  13 from apiclient import errors as apiclient_errors
  14 import errno
  15 import time
  16
  17 from fusefile import StringFile, ObjectFile, FuncToJSONFile, FuseArvadosFile
  18 from fresh import FreshBase, convertTime, use_counter, check_update
  19
  20 import arvados.collection
  21 from arvados.util import portable_data_hash_pattern, uuid_pattern, collection_uuid_pattern, group_uuid_pattern, user_uuid_pattern, link_uuid_pattern
  22
  23 _logger = logging.getLogger('arvados.arvados_fuse')
  24
  25
  26 # Match any character which FUSE or Linux cannot accommodate as part
  27 # of a filename. (If present in a collection filename, they will
  28 # appear as underscores in the fuse mount.)
  29 _disallowed_filename_characters = re.compile('[\x00/]')
  30
  31 # '.' and '..' are not reachable if API server is newer than #6277
  32 def sanitize_filename(dirty):
  33     """Replace disallowed filename characters with harmless "_"."""
  34     if dirty is None:
  35         return None
  36     elif dirty == '':
  37         return '_'
  38     elif dirty == '.':
  39         return '_'
  40     elif dirty == '..':
  41         return '__'
  42     else:
  43         return _disallowed_filename_characters.sub('_', dirty)
  44
  45
  46 class Directory(FreshBase):
  47     """Generic directory object, backed by a dict.
  48
  49     Consists of a set of entries with the key representing the filename
  50     and the value referencing a File or Directory object.
  51     """
  52
  53     def __init__(self, parent_inode, inodes):
  54         """parent_inode is the integer inode number"""
  55
  56         super(Directory, self).__init__()
  57
  58         self.inode = None
  59         if not isinstance(parent_inode, int):
  60             raise Exception("parent_inode should be an int")
  61         self.parent_inode = parent_inode
  62         self.inodes = inodes
  63         self._entries = {}
  64         self._mtime = time.time()
  65
  66     #  Overriden by subclasses to implement logic to update the entries dict
  67     #  when the directory is stale
  68     @use_counter
  69     def update(self):
  70         pass
  71
  72     # Only used when computing the size of the disk footprint of the directory
  73     # (stub)
  74     def size(self):
  75         return 0
  76
  77     def persisted(self):
  78         return False
  79
  80     def checkupdate(self):
  81         if self.stale():
  82             try:
  83                 self.update()
  84             except apiclient.errors.HttpError as e:
  85                 _logger.warn(e)
  86
  87     @use_counter
  88     @check_update
  89     def __getitem__(self, item):
  90         return self._entries[item]
  91
  92     @use_counter
  93     @check_update
  94     def items(self):
  95         return list(self._entries.items())
  96
  97     @use_counter
  98     @check_update
  99     def __contains__(self, k):
 100         return k in self._entries
 101
 102     @use_counter
 103     @check_update
 104     def __len__(self):
 105         return len(self._entries)
 106
 107     def fresh(self):
 108         self.inodes.touch(self)
 109         super(Directory, self).fresh()
 110
 111     def merge(self, items, fn, same, new_entry):
 112         """Helper method for updating the contents of the directory.
 113
 114         Takes a list describing the new contents of the directory, reuse
 115         entries that are the same in both the old and new lists, create new
 116         entries, and delete old entries missing from the new list.
 117
 118         :items: iterable with new directory contents
 119
 120         :fn: function to take an entry in 'items' and return the desired file or
 121         directory name, or None if this entry should be skipped
 122
 123         :same: function to compare an existing entry (a File or Directory
 124         object) with an entry in the items list to determine whether to keep
 125         the existing entry.
 126
 127         :new_entry: function to create a new directory entry (File or Directory
 128         object) from an entry in the items list.
 129
 130         """
 131
 132         oldentries = self._entries
 133         self._entries = {}
 134         changed = False
 135         for i in items:
 136             name = sanitize_filename(fn(i))
 137             if name:
 138                 if name in oldentries and same(oldentries[name], i):
 139                     # move existing directory entry over
 140                     self._entries[name] = oldentries[name]
 141                     del oldentries[name]
 142                 else:
 143                     _logger.debug("Adding entry '%s' to inode %i", name, self.inode)
 144                     # create new directory entry
 145                     ent = new_entry(i)
 146                     if ent is not None:
 147                         self._entries[name] = self.inodes.add_entry(ent)
 148                         changed = True
 149
 150         # delete any other directory entries that were not in found in 'items'
 151         for i in oldentries:
 152             _logger.debug("Forgetting about entry '%s' on inode %i", i, self.inode)
 153             self.inodes.invalidate_entry(self.inode, i.encode(self.inodes.encoding))
 154             self.inodes.del_entry(oldentries[i])
 155             changed = True
 156
 157         if changed:
 158             self.inodes.invalidate_inode(self.inode)
 159             self._mtime = time.time()
 160
 161         self.fresh()
 162
 163     def in_use(self):
 164         if super(Directory, self).in_use():
 165             return True
 166         for v in self._entries.itervalues():
 167             if v.in_use():
 168                 return True
 169         return False
 170
 171     def has_ref(self, only_children):
 172         if super(Directory, self).has_ref(only_children):
 173             return True
 174         for v in self._entries.itervalues():
 175             if v.has_ref(False):
 176                 return True
 177         return False
 178
 179     def clear(self):
 180         """Delete all entries"""
 181         oldentries = self._entries
 182         self._entries = {}
 183         for n in oldentries:
 184             oldentries[n].clear()
 185             self.inodes.invalidate_entry(self.inode, n.encode(self.inodes.encoding))
 186             self.inodes.del_entry(oldentries[n])
 187         self.inodes.invalidate_inode(self.inode)
 188         self.invalidate()
 189
 190     def kernel_invalidate(self):
 191         for n, e in self._entries.iteritems():
 192             self.inodes.invalidate_entry(self.inode, n.encode(self.inodes.encoding))
 193             e.kernel_invalidate()
 194         self.inodes.invalidate_inode(self.inode)
 195
 196     def mtime(self):
 197         return self._mtime
 198
 199     def writable(self):
 200         return False
 201
 202     def flush(self):
 203         pass
 204
 205     def want_event_subscribe(self):
 206         raise NotImplementedError()
 207
 208     def create(self, name):
 209         raise NotImplementedError()
 210
 211     def mkdir(self, name):
 212         raise NotImplementedError()
 213
 214     def unlink(self, name):
 215         raise NotImplementedError()
 216
 217     def rmdir(self, name):
 218         raise NotImplementedError()
 219
 220     def rename(self, name_old, name_new, src):
 221         raise NotImplementedError()
 222
 223
 224 class CollectionDirectoryBase(Directory):
 225     """Represent an Arvados Collection as a directory.
 226
 227     This class is used for Subcollections, and is also the base class for
 228     CollectionDirectory, which implements collection loading/saving on
 229     Collection records.
 230
 231     Most operations act only the underlying Arvados `Collection` object.  The
 232     `Collection` object signals via a notify callback to
 233     `CollectionDirectoryBase.on_event` that an item was added, removed or
 234     modified.  FUSE inodes and directory entries are created, deleted or
 235     invalidated in response to these events.
 236
 237     """
 238
 239     def __init__(self, parent_inode, inodes, collection):
 240         super(CollectionDirectoryBase, self).__init__(parent_inode, inodes)
 241         self.collection = collection
 242
 243     def new_entry(self, name, item, mtime):
 244         name = sanitize_filename(name)
 245         if hasattr(item, "fuse_entry") and item.fuse_entry is not None:
 246             if item.fuse_entry.dead is not True:
 247                 raise Exception("Can only reparent dead inode entry")
 248             if item.fuse_entry.inode is None:
 249                 raise Exception("Reparented entry must still have valid inode")
 250             item.fuse_entry.dead = False
 251             self._entries[name] = item.fuse_entry
 252         elif isinstance(item, arvados.collection.RichCollectionBase):
 253             self._entries[name] = self.inodes.add_entry(CollectionDirectoryBase(self.inode, self.inodes, item))
 254             self._entries[name].populate(mtime)
 255         else:
 256             self._entries[name] = self.inodes.add_entry(FuseArvadosFile(self.inode, item, mtime))
 257         item.fuse_entry = self._entries[name]
 258
 259     def on_event(self, event, collection, name, item):
 260         if collection == self.collection:
 261             name = sanitize_filename(name)
 262             _logger.debug("collection notify %s %s %s %s", event, collection, name, item)
 263             with llfuse.lock:
 264                 if event == arvados.collection.ADD:
 265                     self.new_entry(name, item, self.mtime())
 266                 elif event == arvados.collection.DEL:
 267                     ent = self._entries[name]
 268                     del self._entries[name]
 269                     self.inodes.invalidate_entry(self.inode, name.encode(self.inodes.encoding))
 270                     self.inodes.del_entry(ent)
 271                 elif event == arvados.collection.MOD:
 272                     if hasattr(item, "fuse_entry") and item.fuse_entry is not None:
 273                         self.inodes.invalidate_inode(item.fuse_entry.inode)
 274                     elif name in self._entries:
 275                         self.inodes.invalidate_inode(self._entries[name].inode)
 276
 277     def populate(self, mtime):
 278         self._mtime = mtime
 279         self.collection.subscribe(self.on_event)
 280         for entry, item in self.collection.items():
 281             self.new_entry(entry, item, self.mtime())
 282
 283     def writable(self):
 284         return self.collection.writable()
 285
 286     @use_counter
 287     def flush(self):
 288         with llfuse.lock_released:
 289             self.collection.root_collection().save()
 290
 291     @use_counter
 292     @check_update
 293     def create(self, name):
 294         with llfuse.lock_released:
 295             self.collection.open(name, "w").close()
 296
 297     @use_counter
 298     @check_update
 299     def mkdir(self, name):
 300         with llfuse.lock_released:
 301             self.collection.mkdirs(name)
 302
 303     @use_counter
 304     @check_update
 305     def unlink(self, name):
 306         with llfuse.lock_released:
 307             self.collection.remove(name)
 308         self.flush()
 309
 310     @use_counter
 311     @check_update
 312     def rmdir(self, name):
 313         with llfuse.lock_released:
 314             self.collection.remove(name)
 315         self.flush()
 316
 317     @use_counter
 318     @check_update
 319     def rename(self, name_old, name_new, src):
 320         if not isinstance(src, CollectionDirectoryBase):
 321             raise llfuse.FUSEError(errno.EPERM)
 322
 323         if name_new in self:
 324             ent = src[name_old]
 325             tgt = self[name_new]
 326             if isinstance(ent, FuseArvadosFile) and isinstance(tgt, FuseArvadosFile):
 327                 pass
 328             elif isinstance(ent, CollectionDirectoryBase) and isinstance(tgt, CollectionDirectoryBase):
 329                 if len(tgt) > 0:
 330                     raise llfuse.FUSEError(errno.ENOTEMPTY)
 331             elif isinstance(ent, CollectionDirectoryBase) and isinstance(tgt, FuseArvadosFile):
 332                 raise llfuse.FUSEError(errno.ENOTDIR)
 333             elif isinstance(ent, FuseArvadosFile) and isinstance(tgt, CollectionDirectoryBase):
 334                 raise llfuse.FUSEError(errno.EISDIR)
 335
 336         with llfuse.lock_released:
 337             self.collection.rename(name_old, name_new, source_collection=src.collection, overwrite=True)
 338         self.flush()
 339         src.flush()
 340
 341     def clear(self):
 342         super(CollectionDirectoryBase, self).clear()
 343         self.collection = None
 344
 345
 346 class CollectionDirectory(CollectionDirectoryBase):
 347     """Represents the root of a directory tree representing a collection."""
 348
 349     def __init__(self, parent_inode, inodes, api, num_retries, collection_record=None, explicit_collection=None):
 350         super(CollectionDirectory, self).__init__(parent_inode, inodes, None)
 351         self.api = api
 352         self.num_retries = num_retries
 353         self.collection_record_file = None
 354         self.collection_record = None
 355         self._poll = True
 356         try:
 357             self._poll_time = (api._rootDesc.get('blobSignatureTtl', 60*60*2)/2)
 358         except:
 359             _logger.debug("Error getting blobSignatureTtl from discovery document: %s", sys.exc_info()[0])
 360             self._poll_time = 60*60
 361
 362         if isinstance(collection_record, dict):
 363             self.collection_locator = collection_record['uuid']
 364             self._mtime = convertTime(collection_record.get('modified_at'))
 365         else:
 366             self.collection_locator = collection_record
 367             self._mtime = 0
 368         self._manifest_size = 0
 369         if self.collection_locator:
 370             self._writable = (uuid_pattern.match(self.collection_locator) is not None)
 371         self._updating_lock = threading.Lock()
 372
 373     def same(self, i):
 374         return i['uuid'] == self.collection_locator or i['portable_data_hash'] == self.collection_locator
 375
 376     def writable(self):
 377         return self.collection.writable() if self.collection is not None else self._writable
 378
 379     def want_event_subscribe(self):
 380         return (uuid_pattern.match(self.collection_locator) is not None)
 381
 382     # Used by arv-web.py to switch the contents of the CollectionDirectory
 383     def change_collection(self, new_locator):
 384         """Switch the contents of the CollectionDirectory.
 385
 386         Must be called with llfuse.lock held.
 387         """
 388
 389         self.collection_locator = new_locator
 390         self.collection_record = None
 391         self.update()
 392
 393     def new_collection(self, new_collection_record, coll_reader):
 394         if self.inode:
 395             self.clear()
 396
 397         self.collection_record = new_collection_record
 398
 399         if self.collection_record:
 400             self._mtime = convertTime(self.collection_record.get('modified_at'))
 401             self.collection_locator = self.collection_record["uuid"]
 402             if self.collection_record_file is not None:
 403                 self.collection_record_file.update(self.collection_record)
 404
 405         self.collection = coll_reader
 406         self.populate(self.mtime())
 407
 408     def uuid(self):
 409         return self.collection_locator
 410
 411     @use_counter
 412     def update(self, to_record_version=None):
 413         try:
 414             if self.collection_record is not None and portable_data_hash_pattern.match(self.collection_locator):
 415                 return True
 416
 417             if self.collection_locator is None:
 418                 self.fresh()
 419                 return True
 420
 421             try:
 422                 with llfuse.lock_released:
 423                     self._updating_lock.acquire()
 424                     if not self.stale():
 425                         return
 426
 427                     _logger.debug("Updating collection %s inode %s to record version %s", self.collection_locator, self.inode, to_record_version)
 428                     if self.collection is not None:
 429                         if self.collection.known_past_version(to_record_version):
 430                             _logger.debug("%s already processed %s", self.collection_locator, to_record_version)
 431                         else:
 432                             self.collection.update()
 433                     else:
 434                         if uuid_pattern.match(self.collection_locator):
 435                             coll_reader = arvados.collection.Collection(
 436                                 self.collection_locator, self.api, self.api.keep,
 437                                 num_retries=self.num_retries)
 438                         else:
 439                             coll_reader = arvados.collection.CollectionReader(
 440                                 self.collection_locator, self.api, self.api.keep,
 441                                 num_retries=self.num_retries)
 442                         new_collection_record = coll_reader.api_response() or {}
 443                         # If the Collection only exists in Keep, there will be no API
 444                         # response.  Fill in the fields we need.
 445                         if 'uuid' not in new_collection_record:
 446                             new_collection_record['uuid'] = self.collection_locator
 447                         if "portable_data_hash" not in new_collection_record:
 448                             new_collection_record["portable_data_hash"] = new_collection_record["uuid"]
 449                         if 'manifest_text' not in new_collection_record:
 450                             new_collection_record['manifest_text'] = coll_reader.manifest_text()
 451
 452                         if self.collection_record is None or self.collection_record["portable_data_hash"] != new_collection_record.get("portable_data_hash"):
 453                             self.new_collection(new_collection_record, coll_reader)
 454
 455                         self._manifest_size = len(coll_reader.manifest_text())
 456                         _logger.debug("%s manifest_size %i", self, self._manifest_size)
 457                 # end with llfuse.lock_released, re-acquire lock
 458
 459                 self.fresh()
 460                 return True
 461             finally:
 462                 self._updating_lock.release()
 463         except arvados.errors.NotFoundError as e:
 464             _logger.error("Error fetching collection '%s': %s", self.collection_locator, e)
 465         except arvados.errors.ArgumentError as detail:
 466             _logger.warning("arv-mount %s: error %s", self.collection_locator, detail)
 467             if self.collection_record is not None and "manifest_text" in self.collection_record:
 468                 _logger.warning("arv-mount manifest_text is: %s", self.collection_record["manifest_text"])
 469         except Exception:
 470             _logger.exception("arv-mount %s: error", self.collection_locator)
 471             if self.collection_record is not None and "manifest_text" in self.collection_record:
 472                 _logger.error("arv-mount manifest_text is: %s", self.collection_record["manifest_text"])
 473         self.invalidate()
 474         return False
 475
 476     @use_counter
 477     @check_update
 478     def __getitem__(self, item):
 479         if item == '.arvados#collection':
 480             if self.collection_record_file is None:
 481                 self.collection_record_file = ObjectFile(self.inode, self.collection_record)
 482                 self.inodes.add_entry(self.collection_record_file)
 483             return self.collection_record_file
 484         else:
 485             return super(CollectionDirectory, self).__getitem__(item)
 486
 487     def __contains__(self, k):
 488         if k == '.arvados#collection':
 489             return True
 490         else:
 491             return super(CollectionDirectory, self).__contains__(k)
 492
 493     def invalidate(self):
 494         self.collection_record = None
 495         self.collection_record_file = None
 496         super(CollectionDirectory, self).invalidate()
 497
 498     def persisted(self):
 499         return (self.collection_locator is not None)
 500
 501     def objsize(self):
 502         # This is an empirically-derived heuristic to estimate the memory used
 503         # to store this collection's metadata.  Calculating the memory
 504         # footprint directly would be more accurate, but also more complicated.
 505         return self._manifest_size * 128
 506
 507     def finalize(self):
 508         if self.collection is not None:
 509             if self.writable():
 510                 self.collection.save()
 511             self.collection.stop_threads()
 512
 513     def clear(self):
 514         super(CollectionDirectory, self).clear()
 515         self._manifest_size = 0
 516
 517
 518 class TmpCollectionDirectory(CollectionDirectoryBase):
 519     """A directory backed by an Arvados collection that never gets saved.
 520
 521     This supports using Keep as scratch space. A userspace program can
 522     read the .arvados#collection file to get a current manifest in
 523     order to save a snapshot of the scratch data or use it as a crunch
 524     job output.
 525     """
 526
 527     class UnsaveableCollection(arvados.collection.Collection):
 528         def save(self):
 529             pass
 530         def save_new(self):
 531             pass
 532
 533     def __init__(self, parent_inode, inodes, api_client, num_retries):
 534         collection = self.UnsaveableCollection(
 535             api_client=api_client,
 536             keep_client=api_client.keep,
 537             num_retries=num_retries)
 538         super(TmpCollectionDirectory, self).__init__(
 539             parent_inode, inodes, collection)
 540         self.collection_record_file = None
 541         self.populate(self.mtime())
 542
 543     def on_event(self, *args, **kwargs):
 544         super(TmpCollectionDirectory, self).on_event(*args, **kwargs)
 545         if self.collection_record_file:
 546             with llfuse.lock:
 547                 self.collection_record_file.invalidate()
 548             self.inodes.invalidate_inode(self.collection_record_file.inode)
 549             _logger.debug("%s invalidated collection record", self)
 550
 551     def collection_record(self):
 552         with llfuse.lock_released:
 553             return {
 554                 "uuid": None,
 555                 "manifest_text": self.collection.manifest_text(),
 556                 "portable_data_hash": self.collection.portable_data_hash(),
 557             }
 558
 559     def __contains__(self, k):
 560         return (k == '.arvados#collection' or
 561                 super(TmpCollectionDirectory, self).__contains__(k))
 562
 563     @use_counter
 564     def __getitem__(self, item):
 565         if item == '.arvados#collection':
 566             if self.collection_record_file is None:
 567                 self.collection_record_file = FuncToJSONFile(
 568                     self.inode, self.collection_record)
 569                 self.inodes.add_entry(self.collection_record_file)
 570             return self.collection_record_file
 571         return super(TmpCollectionDirectory, self).__getitem__(item)
 572
 573     def persisted(self):
 574         return False
 575
 576     def writable(self):
 577         return True
 578
 579     def want_event_subscribe(self):
 580         return False
 581
 582     def finalize(self):
 583         self.collection.stop_threads()
 584
 585     def invalidate(self):
 586         if self.collection_record_file:
 587             self.collection_record_file.invalidate()
 588         super(TmpCollectionDirectory, self).invalidate()
 589
 590
 591 class MagicDirectory(Directory):
 592     """A special directory that logically contains the set of all extant keep locators.
 593
 594     When a file is referenced by lookup(), it is tested to see if it is a valid
 595     keep locator to a manifest, and if so, loads the manifest contents as a
 596     subdirectory of this directory with the locator as the directory name.
 597     Since querying a list of all extant keep locators is impractical, only
 598     collections that have already been accessed are visible to readdir().
 599
 600     """
 601
 602     README_TEXT = """
 603 This directory provides access to Arvados collections as subdirectories listed
 604 by uuid (in the form 'zzzzz-4zz18-1234567890abcde') or portable data hash (in
 605 the form '1234567890abcdef0123456789abcdef+123').
 606
 607 Note that this directory will appear empty until you attempt to access a
 608 specific collection subdirectory (such as trying to 'cd' into it), at which
 609 point the collection will actually be looked up on the server and the directory
 610 will appear if it exists.
 611
 612 """.lstrip()
 613
 614     def __init__(self, parent_inode, inodes, api, num_retries, pdh_only=False):
 615         super(MagicDirectory, self).__init__(parent_inode, inodes)
 616         self.api = api
 617         self.num_retries = num_retries
 618         self.pdh_only = pdh_only
 619
 620     def __setattr__(self, name, value):
 621         super(MagicDirectory, self).__setattr__(name, value)
 622         # When we're assigned an inode, add a README.
 623         if ((name == 'inode') and (self.inode is not None) and
 624               (not self._entries)):
 625             self._entries['README'] = self.inodes.add_entry(
 626                 StringFile(self.inode, self.README_TEXT, time.time()))
 627             # If we're the root directory, add an identical by_id subdirectory.
 628             if self.inode == llfuse.ROOT_INODE:
 629                 self._entries['by_id'] = self.inodes.add_entry(MagicDirectory(
 630                         self.inode, self.inodes, self.api, self.num_retries, self.pdh_only))
 631
 632     def __contains__(self, k):
 633         if k in self._entries:
 634             return True
 635
 636         if not portable_data_hash_pattern.match(k) and (self.pdh_only or not uuid_pattern.match(k)):
 637             return False
 638
 639         try:
 640             e = self.inodes.add_entry(CollectionDirectory(
 641                     self.inode, self.inodes, self.api, self.num_retries, k))
 642
 643             if e.update():
 644                 if k not in self._entries:
 645                     self._entries[k] = e
 646                 else:
 647                     self.inodes.del_entry(e)
 648                 return True
 649             else:
 650                 self.inodes.invalidate_entry(self.inode, k)
 651                 self.inodes.del_entry(e)
 652                 return False
 653         except Exception as ex:
 654             _logger.debug('arv-mount exception keep %s', ex)
 655             self.inodes.del_entry(e)
 656             return False
 657
 658     def __getitem__(self, item):
 659         if item in self:
 660             return self._entries[item]
 661         else:
 662             raise KeyError("No collection with id " + item)
 663
 664     def clear(self):
 665         pass
 666
 667     def want_event_subscribe(self):
 668         return not self.pdh_only
 669
 670
 671 class TagsDirectory(Directory):
 672     """A special directory that contains as subdirectories all tags visible to the user."""
 673
 674     def __init__(self, parent_inode, inodes, api, num_retries, poll_time=60):
 675         super(TagsDirectory, self).__init__(parent_inode, inodes)
 676         self.api = api
 677         self.num_retries = num_retries
 678         self._poll = True
 679         self._poll_time = poll_time
 680         self._extra = set()
 681
 682     def want_event_subscribe(self):
 683         return True
 684
 685     @use_counter
 686     def update(self):
 687         with llfuse.lock_released:
 688             tags = self.api.links().list(
 689                 filters=[['link_class', '=', 'tag'], ["name", "!=", ""]],
 690                 select=['name'], distinct=True, limit=1000
 691                 ).execute(num_retries=self.num_retries)
 692         if "items" in tags:
 693             self.merge(tags['items']+[{"name": n} for n in self._extra],
 694                        lambda i: i['name'],
 695                        lambda a, i: a.tag == i['name'],
 696                        lambda i: TagDirectory(self.inode, self.inodes, self.api, self.num_retries, i['name'], poll=self._poll, poll_time=self._poll_time))
 697
 698     def __contains__(self, k):
 699         if super(TagsDirectory, self).__contains__(k):
 700             return True
 701         else:
 702             with llfuse.lock_released:
 703                 tags = self.api.links().list(
 704                     filters=[['link_class', '=', 'tag'], ['name', '=', k]], limit=1
 705                 ).execute(num_retries=self.num_retries)
 706             if tags["items"]:
 707                 self._extra.add(k)
 708                 self.invalidate()
 709                 return True
 710             else:
 711                 return False
 712
 713
 714 class TagDirectory(Directory):
 715     """A special directory that contains as subdirectories all collections visible
 716     to the user that are tagged with a particular tag.
 717     """
 718
 719     def __init__(self, parent_inode, inodes, api, num_retries, tag,
 720                  poll=False, poll_time=60):
 721         super(TagDirectory, self).__init__(parent_inode, inodes)
 722         self.api = api
 723         self.num_retries = num_retries
 724         self.tag = tag
 725         self._poll = poll
 726         self._poll_time = poll_time
 727
 728     def want_event_subscribe(self):
 729         return True
 730
 731     @use_counter
 732     def update(self):
 733         with llfuse.lock_released:
 734             taggedcollections = self.api.links().list(
 735                 filters=[['link_class', '=', 'tag'],
 736                          ['name', '=', self.tag],
 737                          ['head_uuid', 'is_a', 'arvados#collection']],
 738                 select=['head_uuid']
 739                 ).execute(num_retries=self.num_retries)
 740         self.merge(taggedcollections['items'],
 741                    lambda i: i['head_uuid'],
 742                    lambda a, i: a.collection_locator == i['head_uuid'],
 743                    lambda i: CollectionDirectory(self.inode, self.inodes, self.api, self.num_retries, i['head_uuid']))
 744
 745
 746 class ProjectDirectory(Directory):
 747     """A special directory that contains the contents of a project."""
 748
 749     def __init__(self, parent_inode, inodes, api, num_retries, project_object,
 750                  poll=False, poll_time=60):
 751         super(ProjectDirectory, self).__init__(parent_inode, inodes)
 752         self.api = api
 753         self.num_retries = num_retries
 754         self.project_object = project_object
 755         self.project_object_file = None
 756         self.project_uuid = project_object['uuid']
 757         self._poll = poll
 758         self._poll_time = poll_time
 759         self._updating_lock = threading.Lock()
 760         self._current_user = None
 761
 762     def want_event_subscribe(self):
 763         return True
 764
 765     def createDirectory(self, i):
 766         if collection_uuid_pattern.match(i['uuid']):
 767             return CollectionDirectory(self.inode, self.inodes, self.api, self.num_retries, i)
 768         elif group_uuid_pattern.match(i['uuid']):
 769             return ProjectDirectory(self.inode, self.inodes, self.api, self.num_retries, i, self._poll, self._poll_time)
 770         elif link_uuid_pattern.match(i['uuid']):
 771             if i['head_kind'] == 'arvados#collection' or portable_data_hash_pattern.match(i['head_uuid']):
 772                 return CollectionDirectory(self.inode, self.inodes, self.api, self.num_retries, i['head_uuid'])
 773             else:
 774                 return None
 775         elif uuid_pattern.match(i['uuid']):
 776             return ObjectFile(self.parent_inode, i)
 777         else:
 778             return None
 779
 780     def uuid(self):
 781         return self.project_uuid
 782
 783     @use_counter
 784     def update(self):
 785         if self.project_object_file == None:
 786             self.project_object_file = ObjectFile(self.inode, self.project_object)
 787             self.inodes.add_entry(self.project_object_file)
 788
 789         def namefn(i):
 790             if 'name' in i:
 791                 if i['name'] is None or len(i['name']) == 0:
 792                     return None
 793                 elif collection_uuid_pattern.match(i['uuid']) or group_uuid_pattern.match(i['uuid']):
 794                     # collection or subproject
 795                     return i['name']
 796                 elif link_uuid_pattern.match(i['uuid']) and i['head_kind'] == 'arvados#collection':
 797                     # name link
 798                     return i['name']
 799                 elif 'kind' in i and i['kind'].startswith('arvados#'):
 800                     # something else
 801                     return "{}.{}".format(i['name'], i['kind'][8:])
 802             else:
 803                 return None
 804
 805         def samefn(a, i):
 806             if isinstance(a, CollectionDirectory) or isinstance(a, ProjectDirectory):
 807                 return a.uuid() == i['uuid']
 808             elif isinstance(a, ObjectFile):
 809                 return a.uuid() == i['uuid'] and not a.stale()
 810             return False
 811
 812         try:
 813             with llfuse.lock_released:
 814                 self._updating_lock.acquire()
 815                 if not self.stale():
 816                     return
 817
 818                 if group_uuid_pattern.match(self.project_uuid):
 819                     self.project_object = self.api.groups().get(
 820                         uuid=self.project_uuid).execute(num_retries=self.num_retries)
 821                 elif user_uuid_pattern.match(self.project_uuid):
 822                     self.project_object = self.api.users().get(
 823                         uuid=self.project_uuid).execute(num_retries=self.num_retries)
 824
 825                 contents = arvados.util.list_all(self.api.groups().contents,
 826                                                  self.num_retries, uuid=self.project_uuid)
 827
 828             # end with llfuse.lock_released, re-acquire lock
 829
 830             self.merge(contents,
 831                        namefn,
 832                        samefn,
 833                        self.createDirectory)
 834         finally:
 835             self._updating_lock.release()
 836
 837     @use_counter
 838     @check_update
 839     def __getitem__(self, item):
 840         if item == '.arvados#project':
 841             return self.project_object_file
 842         else:
 843             return super(ProjectDirectory, self).__getitem__(item)
 844
 845     def __contains__(self, k):
 846         if k == '.arvados#project':
 847             return True
 848         else:
 849             return super(ProjectDirectory, self).__contains__(k)
 850
 851     @use_counter
 852     @check_update
 853     def writable(self):
 854         with llfuse.lock_released:
 855             if not self._current_user:
 856                 self._current_user = self.api.users().current().execute(num_retries=self.num_retries)
 857             return self._current_user["uuid"] in self.project_object["writable_by"]
 858
 859     def persisted(self):
 860         return True
 861
 862     @use_counter
 863     @check_update
 864     def mkdir(self, name):
 865         try:
 866             with llfuse.lock_released:
 867                 self.api.collections().create(body={"owner_uuid": self.project_uuid,
 868                                                     "name": name,
 869                                                     "manifest_text": ""}).execute(num_retries=self.num_retries)
 870             self.invalidate()
 871         except apiclient_errors.Error as error:
 872             _logger.error(error)
 873             raise llfuse.FUSEError(errno.EEXIST)
 874
 875     @use_counter
 876     @check_update
 877     def rmdir(self, name):
 878         if name not in self:
 879             raise llfuse.FUSEError(errno.ENOENT)
 880         if not isinstance(self[name], CollectionDirectory):
 881             raise llfuse.FUSEError(errno.EPERM)
 882         if len(self[name]) > 0:
 883             raise llfuse.FUSEError(errno.ENOTEMPTY)
 884         with llfuse.lock_released:
 885             self.api.collections().delete(uuid=self[name].uuid()).execute(num_retries=self.num_retries)
 886         self.invalidate()
 887
 888     @use_counter
 889     @check_update
 890     def rename(self, name_old, name_new, src):
 891         if not isinstance(src, ProjectDirectory):
 892             raise llfuse.FUSEError(errno.EPERM)
 893
 894         ent = src[name_old]
 895
 896         if not isinstance(ent, CollectionDirectory):
 897             raise llfuse.FUSEError(errno.EPERM)
 898
 899         if name_new in self:
 900             # POSIX semantics for replacing one directory with another is
 901             # tricky (the target directory must be empty, the operation must be
 902             # atomic which isn't possible with the Arvados API as of this
 903             # writing) so don't support that.
 904             raise llfuse.FUSEError(errno.EPERM)
 905
 906         self.api.collections().update(uuid=ent.uuid(),
 907                                       body={"owner_uuid": self.uuid(),
 908                                             "name": name_new}).execute(num_retries=self.num_retries)
 909
 910         # Acually move the entry from source directory to this directory.
 911         del src._entries[name_old]
 912         self._entries[name_new] = ent
 913         self.inodes.invalidate_entry(src.inode, name_old.encode(self.inodes.encoding))
 914
 915
 916 class SharedDirectory(Directory):
 917     """A special directory that represents users or groups who have shared projects with me."""
 918
 919     def __init__(self, parent_inode, inodes, api, num_retries, exclude,
 920                  poll=False, poll_time=60):
 921         super(SharedDirectory, self).__init__(parent_inode, inodes)
 922         self.api = api
 923         self.num_retries = num_retries
 924         self.current_user = api.users().current().execute(num_retries=num_retries)
 925         self._poll = True
 926         self._poll_time = poll_time
 927
 928     @use_counter
 929     def update(self):
 930         with llfuse.lock_released:
 931             all_projects = arvados.util.list_all(
 932                 self.api.groups().list, self.num_retries,
 933                 filters=[['group_class','=','project']])
 934             objects = {}
 935             for ob in all_projects:
 936                 objects[ob['uuid']] = ob
 937
 938             roots = []
 939             root_owners = {}
 940             for ob in all_projects:
 941                 if ob['owner_uuid'] != self.current_user['uuid'] and ob['owner_uuid'] not in objects:
 942                     roots.append(ob)
 943                     root_owners[ob['owner_uuid']] = True
 944
 945             lusers = arvados.util.list_all(
 946                 self.api.users().list, self.num_retries,
 947                 filters=[['uuid','in', list(root_owners)]])
 948             lgroups = arvados.util.list_all(
 949                 self.api.groups().list, self.num_retries,
 950                 filters=[['uuid','in', list(root_owners)]])
 951
 952             users = {}
 953             groups = {}
 954
 955             for l in lusers:
 956                 objects[l["uuid"]] = l
 957             for l in lgroups:
 958                 objects[l["uuid"]] = l
 959
 960             contents = {}
 961             for r in root_owners:
 962                 if r in objects:
 963                     obr = objects[r]
 964                     if obr.get("name"):
 965                         contents[obr["name"]] = obr
 966                     #elif obr.get("username"):
 967                     #    contents[obr["username"]] = obr
 968                     elif "first_name" in obr:
 969                         contents[u"{} {}".format(obr["first_name"], obr["last_name"])] = obr
 970
 971
 972             for r in roots:
 973                 if r['owner_uuid'] not in objects:
 974                     contents[r['name']] = r
 975
 976         # end with llfuse.lock_released, re-acquire lock
 977
 978         try:
 979             self.merge(contents.items(),
 980                        lambda i: i[0],
 981                        lambda a, i: a.uuid() == i[1]['uuid'],
 982                        lambda i: ProjectDirectory(self.inode, self.inodes, self.api, self.num_retries, i[1], poll=self._poll, poll_time=self._poll_time))
 983         except Exception:
 984             _logger.exception()
 985
 986     def want_event_subscribe(self):
 987         return True