smartfile / python-librsync Goto Github PK

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A ctypes wrapper for librsync. Provides signature(), delta(), and patch() functions.

There are three steps necessary to synchronize a file. Two steps are performed on the source file and one on the destination.

1. Generate a signature for the destination file.
2. Generate a delta for the source file (using the signature).
3. Patch the destination file using the generated delta.

Usually, these steps involve remote systems. Here is an example of synchronizing two local files.

import librsync

# The destination file.
dst = open('Resume-v1.0.pdf', 'rb')

# The source file.
src = open('Resume-v1.2.pdf', 'rb')

# Where we will write the synchronized copy.
synced = open('Resume-latest.pdf', 'wb')

# Step 1: prepare signature of the destination file
signature = librsync.signature(dst)

# Step 2: prepare a delta of the source file
delta = librsync.delta(src, signature)

# Step 3: synchronize the files.
# In many cases, you would overwrite the destination with the result of
# synchronization. However, by default a new file is created.
librsync.patch(dst, delta, synced)

This wrapper only exposes the most common operations that librsync provides. It is not meant to be a full wrapper, but should cover most use-cases. You can easily extend this wrapper. Information about librsync is available in it's manual which is linked below (I wish I had found this BEFORE writing this wrapper!)

http://rproxy.samba.org/doxygen/librsync/refman.pdf