# Copyright (C) The Arvados Authors. All rights reserved. # # SPDX-License-Identifier: Apache-2.0 from __future__ import absolute_import from __future__ import division from future import standard_library from future.utils import listitems, listvalues standard_library.install_aliases() from builtins import range from builtins import object import bz2 import collections import copy import errno import functools import hashlib import logging import os import queue import re import sys import threading import uuid import zlib from . import config from .errors import KeepWriteError, AssertionError, ArgumentError from .keep import KeepLocator from ._normalize_stream import normalize_stream from ._ranges import locators_and_ranges, replace_range, Range, LocatorAndRange from .retry import retry_method MOD = "mod" WRITE = "write" _logger = logging.getLogger('arvados.arvfile') def split(path): """split(path) -> streamname, filename Separate the stream name and file name in a /-separated stream path and return a tuple (stream_name, file_name). If no stream name is available, assume '.'. """ try: stream_name, file_name = path.rsplit('/', 1) except ValueError: # No / in string stream_name, file_name = '.', path return stream_name, file_name class UnownedBlockError(Exception): """Raised when there's an writable block without an owner on the BlockManager.""" pass class _FileLikeObjectBase(object): def __init__(self, name, mode): self.name = name self.mode = mode self.closed = False @staticmethod def _before_close(orig_func): @functools.wraps(orig_func) def before_close_wrapper(self, *args, **kwargs): if self.closed: raise ValueError("I/O operation on closed stream file") return orig_func(self, *args, **kwargs) return before_close_wrapper def __enter__(self): return self def __exit__(self, exc_type, exc_value, traceback): try: self.close() except Exception: if exc_type is None: raise def close(self): self.closed = True class ArvadosFileReaderBase(_FileLikeObjectBase): def __init__(self, name, mode, num_retries=None): super(ArvadosFileReaderBase, self).__init__(name, mode) self._filepos = 0 self.num_retries = num_retries self._readline_cache = (None, None) def __iter__(self): while True: data = self.readline() if not data: break yield data def decompressed_name(self): return re.sub('\.(bz2|gz)$', '', self.name) @_FileLikeObjectBase._before_close def seek(self, pos, whence=os.SEEK_SET): if whence == os.SEEK_CUR: pos += self._filepos elif whence == os.SEEK_END: pos += self.size() if pos < 0: raise IOError(errno.EINVAL, "Tried to seek to negative file offset.") self._filepos = pos return self._filepos def tell(self): return self._filepos def readable(self): return True def writable(self): return False def seekable(self): return True @_FileLikeObjectBase._before_close @retry_method def readall(self, size=2**20, num_retries=None): while True: data = self.read(size, num_retries=num_retries) if len(data) == 0: break yield data @_FileLikeObjectBase._before_close @retry_method def readline(self, size=float('inf'), num_retries=None): cache_pos, cache_data = self._readline_cache if self.tell() == cache_pos: data = [cache_data] self._filepos += len(cache_data) else: data = [b''] data_size = len(data[-1]) while (data_size < size) and (b'\n' not in data[-1]): next_read = self.read(2 ** 20, num_retries=num_retries) if not next_read: break data.append(next_read) data_size += len(next_read) data = b''.join(data) try: nextline_index = data.index(b'\n') + 1 except ValueError: nextline_index = len(data) nextline_index = min(nextline_index, size) self._filepos -= len(data) - nextline_index self._readline_cache = (self.tell(), data[nextline_index:]) return data[:nextline_index].decode() @_FileLikeObjectBase._before_close @retry_method def decompress(self, decompress, size, num_retries=None): for segment in self.readall(size, num_retries=num_retries): data = decompress(segment) if data: yield data @_FileLikeObjectBase._before_close @retry_method def readall_decompressed(self, size=2**20, num_retries=None): self.seek(0) if self.name.endswith('.bz2'): dc = bz2.BZ2Decompressor() return self.decompress(dc.decompress, size, num_retries=num_retries) elif self.name.endswith('.gz'): dc = zlib.decompressobj(16+zlib.MAX_WBITS) return self.decompress(lambda segment: dc.decompress(dc.unconsumed_tail + segment), size, num_retries=num_retries) else: return self.readall(size, num_retries=num_retries) @_FileLikeObjectBase._before_close @retry_method def readlines(self, sizehint=float('inf'), num_retries=None): data = [] data_size = 0 for s in self.readall(num_retries=num_retries): data.append(s) data_size += len(s) if data_size >= sizehint: break return b''.join(data).decode().splitlines(True) def size(self): raise IOError(errno.ENOSYS, "Not implemented") def read(self, size, num_retries=None): raise IOError(errno.ENOSYS, "Not implemented") def readfrom(self, start, size, num_retries=None): raise IOError(errno.ENOSYS, "Not implemented") class StreamFileReader(ArvadosFileReaderBase): class _NameAttribute(str): # The Python file API provides a plain .name attribute. # Older SDK provided a name() method. # This class provides both, for maximum compatibility. def __call__(self): return self def __init__(self, stream, segments, name): super(StreamFileReader, self).__init__(self._NameAttribute(name), 'rb', num_retries=stream.num_retries) self._stream = stream self.segments = segments def stream_name(self): return self._stream.name() def size(self): n = self.segments[-1] return n.range_start + n.range_size @_FileLikeObjectBase._before_close @retry_method def read(self, size, num_retries=None): """Read up to 'size' bytes from the stream, starting at the current file position""" if size == 0: return b'' data = b'' available_chunks = locators_and_ranges(self.segments, self._filepos, size) if available_chunks: lr = available_chunks[0] data = self._stream.readfrom(lr.locator+lr.segment_offset, lr.segment_size, num_retries=num_retries) self._filepos += len(data) return data @_FileLikeObjectBase._before_close @retry_method def readfrom(self, start, size, num_retries=None): """Read up to 'size' bytes from the stream, starting at 'start'""" if size == 0: return b'' data = [] for lr in locators_and_ranges(self.segments, start, size): data.append(self._stream.readfrom(lr.locator+lr.segment_offset, lr.segment_size, num_retries=num_retries)) return b''.join(data) def as_manifest(self): segs = [] for r in self.segments: segs.extend(self._stream.locators_and_ranges(r.locator, r.range_size)) return " ".join(normalize_stream(".", {self.name: segs})) + "\n" def synchronized(orig_func): @functools.wraps(orig_func) def synchronized_wrapper(self, *args, **kwargs): with self.lock: return orig_func(self, *args, **kwargs) return synchronized_wrapper class StateChangeError(Exception): def __init__(self, message, state, nextstate): super(StateChangeError, self).__init__(message) self.state = state self.nextstate = nextstate class _BufferBlock(object): """A stand-in for a Keep block that is in the process of being written. Writers can append to it, get the size, and compute the Keep locator. There are three valid states: WRITABLE Can append to block. PENDING Block is in the process of being uploaded to Keep, append is an error. COMMITTED The block has been written to Keep, its internal buffer has been released, fetching the block will fetch it via keep client (since we discarded the internal copy), and identifiers referring to the BufferBlock can be replaced with the block locator. """ WRITABLE = 0 PENDING = 1 COMMITTED = 2 ERROR = 3 DELETED = 4 def __init__(self, blockid, starting_capacity, owner): """ :blockid: the identifier for this block :starting_capacity: the initial buffer capacity :owner: ArvadosFile that owns this block """ self.blockid = blockid self.buffer_block = bytearray(starting_capacity) self.buffer_view = memoryview(self.buffer_block) self.write_pointer = 0 self._state = _BufferBlock.WRITABLE self._locator = None self.owner = owner self.lock = threading.Lock() self.wait_for_commit = threading.Event() self.error = None @synchronized def append(self, data): """Append some data to the buffer. Only valid if the block is in WRITABLE state. Implements an expanding buffer, doubling capacity as needed to accomdate all the data. """ if self._state == _BufferBlock.WRITABLE: if not isinstance(data, bytes) and not isinstance(data, memoryview): data = data.encode() while (self.write_pointer+len(data)) > len(self.buffer_block): new_buffer_block = bytearray(len(self.buffer_block) * 2) new_buffer_block[0:self.write_pointer] = self.buffer_block[0:self.write_pointer] self.buffer_block = new_buffer_block self.buffer_view = memoryview(self.buffer_block) self.buffer_view[self.write_pointer:self.write_pointer+len(data)] = data self.write_pointer += len(data) self._locator = None else: raise AssertionError("Buffer block is not writable") STATE_TRANSITIONS = frozenset([ (WRITABLE, PENDING), (PENDING, COMMITTED), (PENDING, ERROR), (ERROR, PENDING)]) @synchronized def set_state(self, nextstate, val=None): if (self._state, nextstate) not in self.STATE_TRANSITIONS: raise StateChangeError("Invalid state change from %s to %s" % (self._state, nextstate), self._state, nextstate) self._state = nextstate if self._state == _BufferBlock.PENDING: self.wait_for_commit.clear() if self._state == _BufferBlock.COMMITTED: self._locator = val self.buffer_view = None self.buffer_block = None self.wait_for_commit.set() if self._state == _BufferBlock.ERROR: self.error = val self.wait_for_commit.set() @synchronized def state(self): return self._state def size(self): """The amount of data written to the buffer.""" return self.write_pointer @synchronized def locator(self): """The Keep locator for this buffer's contents.""" if self._locator is None: self._locator = "%s+%i" % (hashlib.md5(self.buffer_view[0:self.write_pointer]).hexdigest(), self.size()) return self._locator @synchronized def clone(self, new_blockid, owner): if self._state == _BufferBlock.COMMITTED: raise AssertionError("Cannot duplicate committed buffer block") bufferblock = _BufferBlock(new_blockid, self.size(), owner) bufferblock.append(self.buffer_view[0:self.size()]) return bufferblock @synchronized def clear(self): self._state = _BufferBlock.DELETED self.owner = None self.buffer_block = None self.buffer_view = None @synchronized def repack_writes(self): """Optimize buffer block by repacking segments in file sequence. When the client makes random writes, they appear in the buffer block in the sequence they were written rather than the sequence they appear in the file. This makes for inefficient, fragmented manifests. Attempt to optimize by repacking writes in file sequence. """ if self._state != _BufferBlock.WRITABLE: raise AssertionError("Cannot repack non-writable block") segs = self.owner.segments() # Collect the segments that reference the buffer block. bufferblock_segs = [s for s in segs if s.locator == self.blockid] # Collect total data referenced by segments (could be smaller than # bufferblock size if a portion of the file was written and # then overwritten). write_total = sum([s.range_size for s in bufferblock_segs]) if write_total < self.size() or len(bufferblock_segs) > 1: # If there's more than one segment referencing this block, it is # due to out-of-order writes and will produce a fragmented # manifest, so try to optimize by re-packing into a new buffer. contents = self.buffer_view[0:self.write_pointer].tobytes() new_bb = _BufferBlock(None, write_total, None) for t in bufferblock_segs: new_bb.append(contents[t.segment_offset:t.segment_offset+t.range_size]) t.segment_offset = new_bb.size() - t.range_size self.buffer_block = new_bb.buffer_block self.buffer_view = new_bb.buffer_view self.write_pointer = new_bb.write_pointer self._locator = None new_bb.clear() self.owner.set_segments(segs) def __repr__(self): return "" % (self.blockid) class NoopLock(object): def __enter__(self): return self def __exit__(self, exc_type, exc_value, traceback): pass def acquire(self, blocking=False): pass def release(self): pass def must_be_writable(orig_func): @functools.wraps(orig_func) def must_be_writable_wrapper(self, *args, **kwargs): if not self.writable(): raise IOError(errno.EROFS, "Collection is read-only.") return orig_func(self, *args, **kwargs) return must_be_writable_wrapper class _BlockManager(object): """BlockManager handles buffer blocks. Also handles background block uploads, and background block prefetch for a Collection of ArvadosFiles. """ DEFAULT_PUT_THREADS = 2 def __init__(self, keep, copies=None, put_threads=None, num_retries=None, storage_classes_func=None): """keep: KeepClient object to use""" self._keep = keep self._bufferblocks = collections.OrderedDict() self._put_queue = None self._put_threads = None self.lock = threading.Lock() self.prefetch_enabled = True self.num_put_threads = put_threads or _BlockManager.DEFAULT_PUT_THREADS self.copies = copies self.storage_classes = storage_classes_func or (lambda: []) self._pending_write_size = 0 self.threads_lock = threading.Lock() self.padding_block = None self.num_retries = num_retries @synchronized def alloc_bufferblock(self, blockid=None, starting_capacity=2**14, owner=None): """Allocate a new, empty bufferblock in WRITABLE state and return it. :blockid: optional block identifier, otherwise one will be automatically assigned :starting_capacity: optional capacity, otherwise will use default capacity :owner: ArvadosFile that owns this block """ return self._alloc_bufferblock(blockid, starting_capacity, owner) def _alloc_bufferblock(self, blockid=None, starting_capacity=2**14, owner=None): if blockid is None: blockid = str(uuid.uuid4()) bufferblock = _BufferBlock(blockid, starting_capacity=starting_capacity, owner=owner) self._bufferblocks[bufferblock.blockid] = bufferblock return bufferblock @synchronized def dup_block(self, block, owner): """Create a new bufferblock initialized with the content of an existing bufferblock. :block: the buffer block to copy. :owner: ArvadosFile that owns the new block """ new_blockid = str(uuid.uuid4()) bufferblock = block.clone(new_blockid, owner) self._bufferblocks[bufferblock.blockid] = bufferblock return bufferblock @synchronized def is_bufferblock(self, locator): return locator in self._bufferblocks def _commit_bufferblock_worker(self): """Background uploader thread.""" while True: try: bufferblock = self._put_queue.get() if bufferblock is None: return if self.copies is None: loc = self._keep.put(bufferblock.buffer_view[0:bufferblock.write_pointer].tobytes(), num_retries=self.num_retries, classes=self.storage_classes()) else: loc = self._keep.put(bufferblock.buffer_view[0:bufferblock.write_pointer].tobytes(), num_retries=self.num_retries, copies=self.copies, classes=self.storage_classes()) bufferblock.set_state(_BufferBlock.COMMITTED, loc) except Exception as e: bufferblock.set_state(_BufferBlock.ERROR, e) finally: if self._put_queue is not None: self._put_queue.task_done() def start_put_threads(self): with self.threads_lock: if self._put_threads is None: # Start uploader threads. # If we don't limit the Queue size, the upload queue can quickly # grow to take up gigabytes of RAM if the writing process is # generating data more quickly than it can be sent to the Keep # servers. # # With two upload threads and a queue size of 2, this means up to 4 # blocks pending. If they are full 64 MiB blocks, that means up to # 256 MiB of internal buffering, which is the same size as the # default download block cache in KeepClient. self._put_queue = queue.Queue(maxsize=2) self._put_threads = [] for i in range(0, self.num_put_threads): thread = threading.Thread(target=self._commit_bufferblock_worker) self._put_threads.append(thread) thread.daemon = True thread.start() @synchronized def stop_threads(self): """Shut down and wait for background upload and download threads to finish.""" if self._put_threads is not None: for t in self._put_threads: self._put_queue.put(None) for t in self._put_threads: t.join() self._put_threads = None self._put_queue = None def __enter__(self): return self def __exit__(self, exc_type, exc_value, traceback): self.stop_threads() @synchronized def repack_small_blocks(self, force=False, sync=False, closed_file_size=0): """Packs small blocks together before uploading""" self._pending_write_size += closed_file_size # Check if there are enough small blocks for filling up one in full if not (force or (self._pending_write_size >= config.KEEP_BLOCK_SIZE)): return # Search blocks ready for getting packed together before being # committed to Keep. # A WRITABLE block always has an owner. # A WRITABLE block with its owner.closed() implies that its # size is <= KEEP_BLOCK_SIZE/2. try: small_blocks = [b for b in listvalues(self._bufferblocks) if b.state() == _BufferBlock.WRITABLE and b.owner.closed()] except AttributeError: # Writable blocks without owner shouldn't exist. raise UnownedBlockError() if len(small_blocks) <= 1: # Not enough small blocks for repacking return for bb in small_blocks: bb.repack_writes() # Update the pending write size count with its true value, just in case # some small file was opened, written and closed several times. self._pending_write_size = sum([b.size() for b in small_blocks]) if self._pending_write_size < config.KEEP_BLOCK_SIZE and not force: return new_bb = self._alloc_bufferblock() new_bb.owner = [] files = [] while len(small_blocks) > 0 and (new_bb.write_pointer + small_blocks[0].size()) <= config.KEEP_BLOCK_SIZE: bb = small_blocks.pop(0) new_bb.owner.append(bb.owner) self._pending_write_size -= bb.size() new_bb.append(bb.buffer_view[0:bb.write_pointer].tobytes()) files.append((bb, new_bb.write_pointer - bb.size())) self.commit_bufferblock(new_bb, sync=sync) for bb, new_bb_segment_offset in files: newsegs = bb.owner.segments() for s in newsegs: if s.locator == bb.blockid: s.locator = new_bb.blockid s.segment_offset = new_bb_segment_offset+s.segment_offset bb.owner.set_segments(newsegs) self._delete_bufferblock(bb.blockid) def commit_bufferblock(self, block, sync): """Initiate a background upload of a bufferblock. :block: The block object to upload :sync: If `sync` is True, upload the block synchronously. If `sync` is False, upload the block asynchronously. This will return immediately unless the upload queue is at capacity, in which case it will wait on an upload queue slot. """ try: # Mark the block as PENDING so to disallow any more appends. block.set_state(_BufferBlock.PENDING) except StateChangeError as e: if e.state == _BufferBlock.PENDING: if sync: block.wait_for_commit.wait() else: return if block.state() == _BufferBlock.COMMITTED: return elif block.state() == _BufferBlock.ERROR: raise block.error else: raise if sync: try: if self.copies is None: loc = self._keep.put(block.buffer_view[0:block.write_pointer].tobytes(), num_retries=self.num_retries, classes=self.storage_classes()) else: loc = self._keep.put(block.buffer_view[0:block.write_pointer].tobytes(), num_retries=self.num_retries, copies=self.copies, classes=self.storage_classes()) block.set_state(_BufferBlock.COMMITTED, loc) except Exception as e: block.set_state(_BufferBlock.ERROR, e) raise else: self.start_put_threads() self._put_queue.put(block) @synchronized def get_bufferblock(self, locator): return self._bufferblocks.get(locator) @synchronized def get_padding_block(self): """Get a bufferblock 64 MB in size consisting of all zeros, used as padding when using truncate() to extend the size of a file. For reference (and possible future optimization), the md5sum of the padding block is: 7f614da9329cd3aebf59b91aadc30bf0+67108864 """ if self.padding_block is None: self.padding_block = self._alloc_bufferblock(starting_capacity=config.KEEP_BLOCK_SIZE) self.padding_block.write_pointer = config.KEEP_BLOCK_SIZE self.commit_bufferblock(self.padding_block, False) return self.padding_block @synchronized def delete_bufferblock(self, locator): self._delete_bufferblock(locator) def _delete_bufferblock(self, locator): if locator in self._bufferblocks: bb = self._bufferblocks[locator] bb.clear() del self._bufferblocks[locator] def get_block_contents(self, locator, num_retries, cache_only=False): """Fetch a block. First checks to see if the locator is a BufferBlock and return that, if not, passes the request through to KeepClient.get(). """ with self.lock: if locator in self._bufferblocks: bufferblock = self._bufferblocks[locator] if bufferblock.state() != _BufferBlock.COMMITTED: return bufferblock.buffer_view[0:bufferblock.write_pointer].tobytes() else: locator = bufferblock._locator if cache_only: return self._keep.get_from_cache(locator) else: return self._keep.get(locator, num_retries=num_retries) def commit_all(self): """Commit all outstanding buffer blocks. This is a synchronous call, and will not return until all buffer blocks are uploaded. Raises KeepWriteError() if any blocks failed to upload. """ self.repack_small_blocks(force=True, sync=True) with self.lock: items = listitems(self._bufferblocks) for k,v in items: if v.state() != _BufferBlock.COMMITTED and v.owner: # Ignore blocks with a list of owners, as if they're not in COMMITTED # state, they're already being committed asynchronously. if isinstance(v.owner, ArvadosFile): v.owner.flush(sync=False) with self.lock: if self._put_queue is not None: self._put_queue.join() err = [] for k,v in items: if v.state() == _BufferBlock.ERROR: err.append((v.locator(), v.error)) if err: raise KeepWriteError("Error writing some blocks", err, label="block") for k,v in items: # flush again with sync=True to remove committed bufferblocks from # the segments. if v.owner: if isinstance(v.owner, ArvadosFile): v.owner.flush(sync=True) elif isinstance(v.owner, list) and len(v.owner) > 0: # This bufferblock is referenced by many files as a result # of repacking small blocks, so don't delete it when flushing # its owners, just do it after flushing them all. for owner in v.owner: owner.flush(sync=True) self.delete_bufferblock(k) self.stop_threads() def block_prefetch(self, locator): """Initiate a background download of a block. """ if not self.prefetch_enabled: return with self.lock: if locator in self._bufferblocks: return self._keep.block_prefetch(locator) class ArvadosFile(object): """Represent a file in a Collection. ArvadosFile manages the underlying representation of a file in Keep as a sequence of segments spanning a set of blocks, and implements random read/write access. This object may be accessed from multiple threads. """ __slots__ = ('parent', 'name', '_writers', '_committed', '_segments', 'lock', '_current_bblock', 'fuse_entry') def __init__(self, parent, name, stream=[], segments=[]): """ ArvadosFile constructor. :stream: a list of Range objects representing a block stream :segments: a list of Range objects representing segments """ self.parent = parent self.name = name self._writers = set() self._committed = False self._segments = [] self.lock = parent.root_collection().lock for s in segments: self._add_segment(stream, s.locator, s.range_size) self._current_bblock = None def writable(self): return self.parent.writable() @synchronized def permission_expired(self, as_of_dt=None): """Returns True if any of the segment's locators is expired""" for r in self._segments: if KeepLocator(r.locator).permission_expired(as_of_dt): return True return False @synchronized def has_remote_blocks(self): """Returns True if any of the segment's locators has a +R signature""" for s in self._segments: if '+R' in s.locator: return True return False @synchronized def _copy_remote_blocks(self, remote_blocks={}): """Ask Keep to copy remote blocks and point to their local copies. This is called from the parent Collection. :remote_blocks: Shared cache of remote to local block mappings. This is used to avoid doing extra work when blocks are shared by more than one file in different subdirectories. """ for s in self._segments: if '+R' in s.locator: try: loc = remote_blocks[s.locator] except KeyError: loc = self.parent._my_keep().refresh_signature(s.locator) remote_blocks[s.locator] = loc s.locator = loc self.parent.set_committed(False) return remote_blocks @synchronized def segments(self): return copy.copy(self._segments) @synchronized def clone(self, new_parent, new_name): """Make a copy of this file.""" cp = ArvadosFile(new_parent, new_name) cp.replace_contents(self) return cp @must_be_writable @synchronized def replace_contents(self, other): """Replace segments of this file with segments from another `ArvadosFile` object.""" map_loc = {} self._segments = [] for other_segment in other.segments(): new_loc = other_segment.locator if other.parent._my_block_manager().is_bufferblock(other_segment.locator): if other_segment.locator not in map_loc: bufferblock = other.parent._my_block_manager().get_bufferblock(other_segment.locator) if bufferblock.state() != _BufferBlock.WRITABLE: map_loc[other_segment.locator] = bufferblock.locator() else: map_loc[other_segment.locator] = self.parent._my_block_manager().dup_block(bufferblock, self).blockid new_loc = map_loc[other_segment.locator] self._segments.append(Range(new_loc, other_segment.range_start, other_segment.range_size, other_segment.segment_offset)) self.set_committed(False) def __eq__(self, other): if other is self: return True if not isinstance(other, ArvadosFile): return False othersegs = other.segments() with self.lock: if len(self._segments) != len(othersegs): return False for i in range(0, len(othersegs)): seg1 = self._segments[i] seg2 = othersegs[i] loc1 = seg1.locator loc2 = seg2.locator if self.parent._my_block_manager().is_bufferblock(loc1): loc1 = self.parent._my_block_manager().get_bufferblock(loc1).locator() if other.parent._my_block_manager().is_bufferblock(loc2): loc2 = other.parent._my_block_manager().get_bufferblock(loc2).locator() if (KeepLocator(loc1).stripped() != KeepLocator(loc2).stripped() or seg1.range_start != seg2.range_start or seg1.range_size != seg2.range_size or seg1.segment_offset != seg2.segment_offset): return False return True def __ne__(self, other): return not self.__eq__(other) @synchronized def set_segments(self, segs): self._segments = segs @synchronized def set_committed(self, value=True): """Set committed flag. If value is True, set committed to be True. If value is False, set committed to be False for this and all parents. """ if value == self._committed: return self._committed = value if self._committed is False and self.parent is not None: self.parent.set_committed(False) @synchronized def committed(self): """Get whether this is committed or not.""" return self._committed @synchronized def add_writer(self, writer): """Add an ArvadosFileWriter reference to the list of writers""" if isinstance(writer, ArvadosFileWriter): self._writers.add(writer) @synchronized def remove_writer(self, writer, flush): """ Called from ArvadosFileWriter.close(). Remove a writer reference from the list and do some block maintenance tasks. """ self._writers.remove(writer) if flush or self.size() > config.KEEP_BLOCK_SIZE // 2: # File writer closed, not small enough for repacking self.flush() elif self.closed(): # All writers closed and size is adequate for repacking self.parent._my_block_manager().repack_small_blocks(closed_file_size=self.size()) def closed(self): """ Get whether this is closed or not. When the writers list is empty, the file is supposed to be closed. """ return len(self._writers) == 0 @must_be_writable @synchronized def truncate(self, size): """Shrink or expand the size of the file. If `size` is less than the size of the file, the file contents after `size` will be discarded. If `size` is greater than the current size of the file, it will be filled with zero bytes. """ if size < self.size(): new_segs = [] for r in self._segments: range_end = r.range_start+r.range_size if r.range_start >= size: # segment is past the trucate size, all done break elif size < range_end: nr = Range(r.locator, r.range_start, size - r.range_start, 0) nr.segment_offset = r.segment_offset new_segs.append(nr) break else: new_segs.append(r) self._segments = new_segs self.set_committed(False) elif size > self.size(): padding = self.parent._my_block_manager().get_padding_block() diff = size - self.size() while diff > config.KEEP_BLOCK_SIZE: self._segments.append(Range(padding.blockid, self.size(), config.KEEP_BLOCK_SIZE, 0)) diff -= config.KEEP_BLOCK_SIZE if diff > 0: self._segments.append(Range(padding.blockid, self.size(), diff, 0)) self.set_committed(False) else: # size == self.size() pass def readfrom(self, offset, size, num_retries, exact=False): """Read up to `size` bytes from the file starting at `offset`. :exact: If False (default), return less data than requested if the read crosses a block boundary and the next block isn't cached. If True, only return less data than requested when hitting EOF. """ with self.lock: if size == 0 or offset >= self.size(): return b'' readsegs = locators_and_ranges(self._segments, offset, size) prefetch = locators_and_ranges(self._segments, offset + size, config.KEEP_BLOCK_SIZE * self.parent._my_block_manager()._keep.num_prefetch_threads, limit=32) locs = set() data = [] for lr in readsegs: block = self.parent._my_block_manager().get_block_contents(lr.locator, num_retries=num_retries, cache_only=(bool(data) and not exact)) if block: blockview = memoryview(block) data.append(blockview[lr.segment_offset:lr.segment_offset+lr.segment_size].tobytes()) locs.add(lr.locator) else: break for lr in prefetch: if lr.locator not in locs: self.parent._my_block_manager().block_prefetch(lr.locator) locs.add(lr.locator) return b''.join(data) @must_be_writable @synchronized def writeto(self, offset, data, num_retries): """Write `data` to the file starting at `offset`. This will update existing bytes and/or extend the size of the file as necessary. """ if not isinstance(data, bytes) and not isinstance(data, memoryview): data = data.encode() if len(data) == 0: return if offset > self.size(): self.truncate(offset) if len(data) > config.KEEP_BLOCK_SIZE: # Chunk it up into smaller writes n = 0 dataview = memoryview(data) while n < len(data): self.writeto(offset+n, dataview[n:n + config.KEEP_BLOCK_SIZE].tobytes(), num_retries) n += config.KEEP_BLOCK_SIZE return self.set_committed(False) if self._current_bblock is None or self._current_bblock.state() != _BufferBlock.WRITABLE: self._current_bblock = self.parent._my_block_manager().alloc_bufferblock(owner=self) if (self._current_bblock.size() + len(data)) > config.KEEP_BLOCK_SIZE: self._current_bblock.repack_writes() if (self._current_bblock.size() + len(data)) > config.KEEP_BLOCK_SIZE: self.parent._my_block_manager().commit_bufferblock(self._current_bblock, sync=False) self._current_bblock = self.parent._my_block_manager().alloc_bufferblock(owner=self) self._current_bblock.append(data) replace_range(self._segments, offset, len(data), self._current_bblock.blockid, self._current_bblock.write_pointer - len(data)) self.parent.notify(WRITE, self.parent, self.name, (self, self)) return len(data) @synchronized def flush(self, sync=True, num_retries=0): """Flush the current bufferblock to Keep. :sync: If True, commit block synchronously, wait until buffer block has been written. If False, commit block asynchronously, return immediately after putting block into the keep put queue. """ if self.committed(): return if self._current_bblock and self._current_bblock.state() != _BufferBlock.COMMITTED: if self._current_bblock.state() == _BufferBlock.WRITABLE: self._current_bblock.repack_writes() if self._current_bblock.state() != _BufferBlock.DELETED: self.parent._my_block_manager().commit_bufferblock(self._current_bblock, sync=sync) if sync: to_delete = set() for s in self._segments: bb = self.parent._my_block_manager().get_bufferblock(s.locator) if bb: if bb.state() != _BufferBlock.COMMITTED: self.parent._my_block_manager().commit_bufferblock(bb, sync=True) to_delete.add(s.locator) s.locator = bb.locator() for s in to_delete: # Don't delete the bufferblock if it's owned by many files. It'll be # deleted after all of its owners are flush()ed. if self.parent._my_block_manager().get_bufferblock(s).owner is self: self.parent._my_block_manager().delete_bufferblock(s) self.parent.notify(MOD, self.parent, self.name, (self, self)) @must_be_writable @synchronized def add_segment(self, blocks, pos, size): """Add a segment to the end of the file. `pos` and `offset` reference a section of the stream described by `blocks` (a list of Range objects) """ self._add_segment(blocks, pos, size) def _add_segment(self, blocks, pos, size): """Internal implementation of add_segment.""" self.set_committed(False) for lr in locators_and_ranges(blocks, pos, size): last = self._segments[-1] if self._segments else Range(0, 0, 0, 0) r = Range(lr.locator, last.range_start+last.range_size, lr.segment_size, lr.segment_offset) self._segments.append(r) @synchronized def size(self): """Get the file size.""" if self._segments: n = self._segments[-1] return n.range_start + n.range_size else: return 0 @synchronized def manifest_text(self, stream_name=".", portable_locators=False, normalize=False, only_committed=False): buf = "" filestream = [] for segment in self._segments: loc = segment.locator if self.parent._my_block_manager().is_bufferblock(loc): if only_committed: continue loc = self.parent._my_block_manager().get_bufferblock(loc).locator() if portable_locators: loc = KeepLocator(loc).stripped() filestream.append(LocatorAndRange(loc, KeepLocator(loc).size, segment.segment_offset, segment.range_size)) buf += ' '.join(normalize_stream(stream_name, {self.name: filestream})) buf += "\n" return buf @must_be_writable @synchronized def _reparent(self, newparent, newname): self.set_committed(False) self.flush(sync=True) self.parent.remove(self.name) self.parent = newparent self.name = newname self.lock = self.parent.root_collection().lock class ArvadosFileReader(ArvadosFileReaderBase): """Wraps ArvadosFile in a file-like object supporting reading only. Be aware that this class is NOT thread safe as there is no locking around updating file pointer. """ def __init__(self, arvadosfile, mode="r", num_retries=None): super(ArvadosFileReader, self).__init__(arvadosfile.name, mode=mode, num_retries=num_retries) self.arvadosfile = arvadosfile def size(self): return self.arvadosfile.size() def stream_name(self): return self.arvadosfile.parent.stream_name() def readinto(self, b): data = self.read(len(b)) b[:len(data)] = data return len(data) @_FileLikeObjectBase._before_close @retry_method def read(self, size=None, num_retries=None): """Read up to `size` bytes from the file and return the result. Starts at the current file position. If `size` is None, read the entire remainder of the file. """ if size is None: data = [] rd = self.arvadosfile.readfrom(self._filepos, config.KEEP_BLOCK_SIZE, num_retries) while rd: data.append(rd) self._filepos += len(rd) rd = self.arvadosfile.readfrom(self._filepos, config.KEEP_BLOCK_SIZE, num_retries) return b''.join(data) else: data = self.arvadosfile.readfrom(self._filepos, size, num_retries, exact=True) self._filepos += len(data) return data @_FileLikeObjectBase._before_close @retry_method def readfrom(self, offset, size, num_retries=None): """Read up to `size` bytes from the stream, starting at the specified file offset. This method does not change the file position. """ return self.arvadosfile.readfrom(offset, size, num_retries) def flush(self): pass class ArvadosFileWriter(ArvadosFileReader): """Wraps ArvadosFile in a file-like object supporting both reading and writing. Be aware that this class is NOT thread safe as there is no locking around updating file pointer. """ def __init__(self, arvadosfile, mode, num_retries=None): super(ArvadosFileWriter, self).__init__(arvadosfile, mode=mode, num_retries=num_retries) self.arvadosfile.add_writer(self) def writable(self): return True @_FileLikeObjectBase._before_close @retry_method def write(self, data, num_retries=None): if self.mode[0] == "a": self._filepos = self.size() self.arvadosfile.writeto(self._filepos, data, num_retries) self._filepos += len(data) return len(data) @_FileLikeObjectBase._before_close @retry_method def writelines(self, seq, num_retries=None): for s in seq: self.write(s, num_retries=num_retries) @_FileLikeObjectBase._before_close def truncate(self, size=None): if size is None: size = self._filepos self.arvadosfile.truncate(size) @_FileLikeObjectBase._before_close def flush(self): self.arvadosfile.flush() def close(self, flush=True): if not self.closed: self.arvadosfile.remove_writer(self, flush) super(ArvadosFileWriter, self).close() class WrappableFile(object): """An interface to an Arvados file that's compatible with io wrappers. """ def __init__(self, f): self.f = f self.closed = False def close(self): self.closed = True return self.f.close() def flush(self): return self.f.flush() def read(self, *args, **kwargs): return self.f.read(*args, **kwargs) def readable(self): return self.f.readable() def readinto(self, *args, **kwargs): return self.f.readinto(*args, **kwargs) def seek(self, *args, **kwargs): return self.f.seek(*args, **kwargs) def seekable(self): return self.f.seekable() def tell(self): return self.f.tell() def writable(self): return self.f.writable() def write(self, *args, **kwargs): return self.f.write(*args, **kwargs)