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1 files changed, 90 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/fsspec/transaction.py b/.venv/lib/python3.12/site-packages/fsspec/transaction.py
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+++ b/.venv/lib/python3.12/site-packages/fsspec/transaction.py
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+from collections import deque
+
+
+class Transaction:
+ """Filesystem transaction write context
+
+ Gathers files for deferred commit or discard, so that several write
+ operations can be finalized semi-atomically. This works by having this
+ instance as the ``.transaction`` attribute of the given filesystem
+ """
+
+ def __init__(self, fs, **kwargs):
+ """
+ Parameters
+ ----------
+ fs: FileSystem instance
+ """
+ self.fs = fs
+ self.files = deque()
+
+ def __enter__(self):
+ self.start()
+ return self
+
+ def __exit__(self, exc_type, exc_val, exc_tb):
+ """End transaction and commit, if exit is not due to exception"""
+ # only commit if there was no exception
+ self.complete(commit=exc_type is None)
+ if self.fs:
+ self.fs._intrans = False
+ self.fs._transaction = None
+ self.fs = None
+
+ def start(self):
+ """Start a transaction on this FileSystem"""
+ self.files = deque() # clean up after previous failed completions
+ self.fs._intrans = True
+
+ def complete(self, commit=True):
+ """Finish transaction: commit or discard all deferred files"""
+ while self.files:
+ f = self.files.popleft()
+ if commit:
+ f.commit()
+ else:
+ f.discard()
+ self.fs._intrans = False
+ self.fs._transaction = None
+ self.fs = None
+
+
+class FileActor:
+ def __init__(self):
+ self.files = []
+
+ def commit(self):
+ for f in self.files:
+ f.commit()
+ self.files.clear()
+
+ def discard(self):
+ for f in self.files:
+ f.discard()
+ self.files.clear()
+
+ def append(self, f):
+ self.files.append(f)
+
+
+class DaskTransaction(Transaction):
+ def __init__(self, fs):
+ """
+ Parameters
+ ----------
+ fs: FileSystem instance
+ """
+ import distributed
+
+ super().__init__(fs)
+ client = distributed.default_client()
+ self.files = client.submit(FileActor, actor=True).result()
+
+ def complete(self, commit=True):
+ """Finish transaction: commit or discard all deferred files"""
+ if commit:
+ self.files.commit().result()
+ else:
+ self.files.discard().result()
+ self.fs._intrans = False
+ self.fs = None