async def foo_txt(alice, alice_file_transactions):
local_storage = alice_file_transactions.local_storage
now = datetime(2000, 1, 2)
placeholder = LocalFileManifest.new_placeholder(alice.device_id,
parent=EntryID(),
now=now)
remote_v1 = placeholder.to_remote(author=alice.device_id, timestamp=now)
manifest = LocalFileManifest.from_remote(remote_v1)
async with local_storage.lock_entry_id(manifest.id):
await local_storage.set_manifest(manifest.id, manifest)
return File(local_storage, manifest)
def __init__(self) -> None:
super().__init__()
self.oracle = open(tmpdir / "oracle.txt", "w+b")
self.manifest = LocalFileManifest.new_placeholder(
DeviceID.new(), parent=EntryID(), blocksize=8
)
self.storage = Storage()
def prepare_truncate(
manifest: LocalFileManifest,
size: int) -> Tuple[LocalFileManifest, Set[Union[BlockID, ChunkID]]]:
# Prepare
block, remainder = locate(size, manifest.blocksize)
removed_ids = chunk_id_set(manifest.blocks[block])
# Truncate buffers
blocks = manifest.blocks[:block]
if remainder:
chunks = manifest.blocks[block]
stop_index = index_of_chunk_after_stop(chunks, size)
last_chunk = chunks[stop_index - 1]
chunks = chunks[:stop_index - 1]
chunks += (last_chunk.evolve(stop=size), )
blocks += (chunks, )
removed_ids -= chunk_id_set(chunks)
# Clean up
for chunks in manifest.blocks[block + 1:]:
removed_ids |= chunk_id_set(chunks)
# Craft new manifest
new_manifest = manifest.evolve_and_mark_updated(size=size, blocks=blocks)
# Return truncate result
return new_manifest, removed_ids
def prepare_write(
manifest: LocalFileManifest, size: int, offset: int
) -> Tuple[LocalFileManifest, List[Tuple[Chunk, int]], Set[Union[BlockID,
ChunkID]]]:
# Prepare
padding = 0
removed_ids: Set[Union[BlockID, ChunkID]] = set()
write_operations: List[Tuple[Chunk, int]] = []
# Padding
if offset > manifest.size:
padding = offset - manifest.size
size += padding
offset = manifest.size
# Copy buffers
blocks = list(manifest.blocks)
# Loop over blocks
for block, subsize, start, content_offset in split_write(
size, offset, manifest.blocksize):
# Prepare new chunk
new_chunk = Chunk.new(start, start + subsize)
write_operations.append((new_chunk, content_offset - padding))
# Lazy block write
chunks = manifest.get_chunks(block)
new_chunks, more_removed_ids = block_write(chunks, subsize, start,
new_chunk)
# Update data structures
removed_ids |= more_removed_ids
if len(blocks) == block:
blocks.append(new_chunks)
else:
blocks[block] = new_chunks
# Evolve manifest
new_size = max(manifest.size, offset + size)
new_manifest = manifest.evolve_and_mark_updated(size=new_size,
blocks=tuple(blocks))
# Return write result
return new_manifest, write_operations, removed_ids
def test_merge_file_manifests():
my_device = DeviceID("b@b")
other_device = DeviceID("a@a")
parent = EntryID()
v1 = LocalFileManifest.new_placeholder(
my_device, parent=parent).to_remote(author=other_device)
def evolve(m, n):
chunk = Chunk.new(0, n).evolve_as_block(b"a" * n)
blocks = ((chunk, ), )
return m1.evolve_and_mark_updated(size=n, blocks=blocks)
# Initial base manifest
m1 = LocalFileManifest.from_remote(v1)
assert merge_manifests(my_device, empty_filter, m1) == m1
# Local change
m2 = evolve(m1, 1)
assert merge_manifests(my_device, empty_filter, m2) == m2
# Successful upload
v2 = m2.to_remote(author=my_device)
m3 = merge_manifests(my_device, empty_filter, m2, v2)
assert m3 == LocalFileManifest.from_remote(v2)
# Two local changes
m4 = evolve(m3, 2)
assert merge_manifests(my_device, empty_filter, m4) == m4
m5 = evolve(m4, 3)
assert merge_manifests(my_device, empty_filter, m4) == m4
# M4 has been successfully uploaded
v3 = m4.to_remote(author=my_device)
m6 = merge_manifests(my_device, empty_filter, m5, v3)
assert m6 == m5.evolve(base=v3)
# The remote has changed
v4 = v3.evolve(version=4, size=0, author=other_device)
with pytest.raises(FSFileConflictError):
merge_manifests(my_device, empty_filter, m6, v4)
def prepare_read(manifest: LocalFileManifest, size: int,
offset: int) -> Chunks:
# Prepare
chunks: List[Chunk] = []
offset = min(offset, manifest.size)
size = min(size, manifest.size - offset)
# Loop over blocks
for block, length, start in split_read(size, offset, manifest.blocksize):
# Loop over chunks
block_chunks = manifest.get_chunks(block)
chunks += block_read(block_chunks, length, start)
# Return read result
return tuple(chunks)
async def init(self):
nonlocal tentative
tentative += 1
await reset_testbed()
self.device = alice
await self.start_transactions()
self.file_transactions = self.transactions_controller.file_transactions
self.local_storage = self.file_transactions.local_storage
self.fresh_manifest = LocalFileManifest.new_placeholder(
alice.device_id, parent=EntryID())
self.entry_id = self.fresh_manifest.id
async with self.local_storage.lock_entry_id(self.entry_id):
await self.local_storage.set_manifest(self.entry_id,
self.fresh_manifest)
self.fd = self.local_storage.create_file_descriptor(
self.fresh_manifest)
self.file_oracle_path = tmpdir / f"oracle-test-{tentative}.txt"
self.file_oracle_fd = os.open(self.file_oracle_path,
os.O_RDWR | os.O_CREAT)
async def file_create(
self,
path: FsPath,
open=True) -> Tuple[EntryID, Optional[FileDescriptor]]:
# Check write rights
self.check_write_rights(path)
# Lock parent in write mode
async with self._lock_parent_manifest_from_path(path) as (parent,
child):
# Destination already exists
if child is not None:
raise FSFileExistsError(filename=path)
# Create file
child = LocalFileManifest.new_placeholder(self.local_author,
parent=parent.id)
# New parent manifest
new_parent = parent.evolve_children_and_mark_updated(
{path.name: child.id},
pattern_filter=self.local_storage.get_pattern_filter())
# ~ Atomic change
await self.local_storage.set_manifest(child.id,
child,
check_lock_status=False)
await self.local_storage.set_manifest(parent.id, new_parent)
fd = self.local_storage.create_file_descriptor(
child) if open else None
# Send events
self._send_event(ClientEvent.FS_ENTRY_UPDATED, id=parent.id)
self._send_event(ClientEvent.FS_ENTRY_UPDATED, id=child.id)
# Return the entry id of the created file and the file descriptor
return child.id, fd
def update_manifest(block: int, manifest: LocalFileManifest,
new_chunk: Chunk) -> LocalFileManifest:
blocks = list(manifest.blocks)
blocks[block] = (new_chunk, )
return manifest.evolve(blocks=tuple(blocks))
async def file_conflict(
self,
entry_id: EntryID,
local_manifest: Union[LocalFolderManifest, LocalFileManifest],
remote_manifest: BaseRemoteManifest,
) -> None:
# This is the only transaction that affects more than one manifests
# That's because the local version of the file has to be registered in the
# parent as a new child while the remote version has to be set as the actual
# version. In practice, this should not be an issue.
# Lock parent then child
parent_id = local_manifest.parent
async with self.local_storage.lock_manifest(
parent_id) as parent_manifest:
async with self.local_storage.lock_manifest(
entry_id) as current_manifest:
# Make sure the file still exists
filename = get_filename(parent_manifest, entry_id)
if filename is None:
return
# Copy blocks
new_blocks = []
for chunks in current_manifest.blocks:
new_chunks = []
for chunk in chunks:
data = await self.local_storage.get_chunk(chunk.id)
new_chunk = Chunk.new(chunk.start, chunk.stop)
await self.local_storage.set_chunk(new_chunk.id, data)
if len(chunks) == 1:
new_chunk = new_chunk.evolve_as_block(data)
new_chunks.append(chunk)
new_blocks.append(tuple(new_chunks))
new_blocks: Tuple[Tuple[Any, ...], ...] = tuple(new_blocks)
# Prepare
new_name = get_conflict_filename(
filename, list(parent_manifest.children),
remote_manifest.author)
new_manifest = LocalFileManifest.new_placeholder(
self.local_author,
parent=parent_id).evolve(size=current_manifest.size,
blocks=new_blocks)
new_parent_manifest = parent_manifest.evolve_children_and_mark_updated(
{new_name: new_manifest.id},
pattern_filter=self.local_storage.get_pattern_filter(),
)
other_manifest = BaseLocalManifest.from_remote(remote_manifest)
# Set manifests
await self.local_storage.set_manifest(new_manifest.id,
new_manifest,
check_lock_status=False)
await self.local_storage.set_manifest(parent_id,
new_parent_manifest)
await self.local_storage.set_manifest(entry_id, other_manifest)
self._send_event(ClientEvent.FS_ENTRY_UPDATED,
id=new_manifest.id)
self._send_event(ClientEvent.FS_ENTRY_UPDATED, id=parent_id)
self._send_event(
ClientEvent.FS_ENTRY_FILE_CONFLICT_RESOLVED,
id=entry_id,
backup_id=new_manifest.id,
)
def test_complete_scenario():
storage = Storage()
with freeze_time("2000-01-01"):
base = manifest = LocalFileManifest.new_placeholder(
DeviceID.new(), parent=EntryID(), blocksize=16
)
assert manifest == base.evolve(size=0)
with freeze_time("2000-01-02") as t2:
manifest = storage.write(manifest, b"Hello ", 0)
assert storage.read(manifest, 6, 0) == b"Hello "
((chunk0,),) = manifest.blocks
assert manifest == base.evolve(size=6, blocks=((chunk0,),), updated=t2)
assert chunk0 == Chunk(id=chunk0.id, start=0, stop=6, raw_offset=0, raw_size=6, access=None)
assert storage[chunk0.id] == b"Hello "
with freeze_time("2000-01-03") as t3:
manifest = storage.write(manifest, b"world !", 6)
assert storage.read(manifest, 13, 0) == b"Hello world !"
((_, chunk1),) = manifest.blocks
assert manifest == base.evolve(size=13, blocks=((chunk0, chunk1),), updated=t3)
assert chunk1 == Chunk(id=chunk1.id, start=6, stop=13, raw_offset=6, raw_size=7, access=None)
assert storage[chunk1.id] == b"world !"
with freeze_time("2000-01-04") as t4:
manifest = storage.write(manifest, b"\n More kontent", 13)
assert storage.read(manifest, 27, 0) == b"Hello world !\n More kontent"
(_, _, chunk2), (chunk3,) = manifest.blocks
assert storage[chunk2.id] == b"\n M"
assert storage[chunk3.id] == b"ore kontent"
assert manifest == base.evolve(
size=27, blocks=((chunk0, chunk1, chunk2), (chunk3,)), updated=t4
)
with freeze_time("2000-01-05") as t5:
manifest = storage.write(manifest, b"c", 20)
assert storage.read(manifest, 27, 0) == b"Hello world !\n More content"
chunk4, chunk5, chunk6 = manifest.blocks[1]
assert chunk3.id == chunk4.id == chunk6.id
assert storage[chunk5.id] == b"c"
assert manifest == base.evolve(
size=27, blocks=((chunk0, chunk1, chunk2), (chunk4, chunk5, chunk6)), updated=t5
)
with freeze_time("2000-01-06") as t6:
manifest = storage.resize(manifest, 40)
expected = b"Hello world !\n More content" + b"\x00" * 13
assert storage.read(manifest, 40, 0) == expected
(_, _, _, chunk7), (chunk8,) = manifest.blocks[1:]
assert storage[chunk7.id] == b"\x00" * 5
assert storage[chunk8.id] == b"\x00" * 8
assert manifest == base.evolve(
size=40,
blocks=((chunk0, chunk1, chunk2), (chunk4, chunk5, chunk6, chunk7), (chunk8,)),
updated=t6,
)
with freeze_time("2000-01-07") as t7:
manifest = storage.resize(manifest, 25)
expected = b"Hello world !\n More conte"
assert storage.read(manifest, 25, 0) == expected
((_, _, chunk9),) = manifest.blocks[1:]
assert chunk9.id == chunk6.id
assert manifest == base.evolve(
size=25, blocks=((chunk0, chunk1, chunk2), (chunk4, chunk5, chunk9)), updated=t7
)
with freeze_time("2000-01-08"):
assert not manifest.is_reshaped()
manifest = storage.reshape(manifest)
expected = b"Hello world !\n More conte"
assert storage.read(manifest, 25, 0) == expected
assert manifest.is_reshaped()
(chunk10,), (chunk11,) = manifest.blocks
assert storage[chunk10.id] == b"Hello world !\n M"
assert storage[chunk11.id] == b"ore conte"
assert manifest == base.evolve(size=25, blocks=((chunk10,), (chunk11,)), updated=t7)