[FEATURE] support BackupEngine

[raphaelauv]

would be great to be able to create a backup from python code

WDYT ?

[mahnerak]

aimrocks implements BackupEngine, however, the feature is not tested well.

Consider you have db instance of aimrocks.DB.

To backup:

backup = rocksdb.BackupEngine("test.db/backups")
backup.create_backup(db, flush_before_backup=True)

To restore:

backup = rocksdb.BackupEngine("test.db/backups")
backup.restore_latest_backup("test.db", "test.db")  # the second one is wal directory

You can browse the code for the details: https://github.com/aimhubio/aimrocks/blob/db068474a693a90f209a81d97337864b5a6e1513/src/aimrocks/lib_rocksdb.pyx#L2454-L2465

[raphaelauv]

thank for your answer

I just tried and restore_backup do not return anything

import aimrocks

rocks_db = aimrocks.DB("/tmp/example_db", aimrocks.Options())
rocks_db.put(b'1', b"toto", disable_wal=True)


backup = aimrocks.BackupEngine("test.db/backups")
backup.create_backup(rocks_db, flush_before_backup=True)

del rocks_db

backup = aimrocks.BackupEngine("test.db/backups")
rocks_db = backup.restore_latest_backup("test.db", "test.db")

print(rocks_db.get(b'1'))

give

AttributeError: 'NoneType' object has no attribute 'get'