Systems and methods for restoring a file
Systems and methods for restoring files and metadata records associated with files are provided herein. Some of the methods include identifying a version of the file, evaluating one or more reverse incremental delta increments, and restoring an arbitrary version of the file based on an arbitrary time reference by assembling the arbitrary version of the file based on the one or more reverse incremental delta increments.
1. A method for restoring a metadata record from differential metadata, the method comprising:
identifying a first metadata snapshot associated with the metadata record, the first metadata snapshot including a plurality of nodes corresponding to metadata to be restored;
establishing a time sequence spanning between an arbitrary time reference and a time reference corresponding to the first metadata snapshot;
locating a plurality of differential metadata records created during the time sequence, the plurality of differential metadata records each including nodes corresponding to changes in metadata relative to the first metadata snapshot and one or more empty nodes corresponding to metadata inherited from temporally adjacent differential metadata records or the first metadata snapshot, wherein a node is representative of blocks of data, the node being defined by an offset and a length;
parsing the first metadata snapshot to determine the nodes and create an index for the metadata record to be restored;
opening the plurality of differential metadata records simultaneously;
iterating through each of the nodes of the plurality of differential metadata records;
deferring iteration when a node to be inherited by a second differential metadata record occurs before the currently inheriting node of a first differential metadata record temporally adjacent to the second differential metadata record, the deferring further including recursively iterating at the currently inheriting node of the first differential metadata record until all nodes of the first differential metadata record have been iterated;
inheriting the nodes of the first metadata snapshot, utilizing the index, in reverse chronological order relative to the nodes of the plurality of opened differential metadata records to determine changes between the first metadata snapshot and the metadata record to be restored; and
restoring the metadata record to the arbitrary time reference utilizing the determined changes.
2. The method according to claim 1 , further comprising creating one or more metadata snapshots of metadata at predetermined time intervals.
3. The method according to claim 1 , further comprising creating differential metadata records that includes changes to the metadata taken at secondary time intervals between metadata snapshots taken at predetermined time intervals.
4. The method according to claim 1 , wherein parsing includes iterating through each of the differential metadata records for each node of the first metadata snapshot, wherein a node currently being iterated is available for inheritance through each of the differential metadata records.
5. The method according to claim 1 , wherein if the metadata record to be restored includes differential metadata, the method includes:
locating a first metadata snapshot created before the arbitrary time reference and a second metadata snapshot created after the arbitrary time reference; and
establishing a time sequence spanning between the creation date of the first metadata snapshot and the creation date of the second metadata snapshot.
6. The method according to claim 5 , wherein when before a node is inherited by a differential metadata record from a metadata snapshot, the method includes synthesizing a null node for the metadata snapshot, the null node corresponding to absent nodes in the located differential metadata records.
7. The method according to claim 6 , wherein synthesizing includes parsing all nodes of the metadata snapshot prior to the differential metadata record inheriting the node to determine whether a node to be inherited is absent in the located differential metadata records.
8. A system for restoring a metadata record from differential metadata, the system comprising:
a network coupled to a server and one or more user devices requesting the restoration of the metadata record;
the server comprising a processor that executes instructions stored in memory, the memory comprising:
a file locator module adapted to:
identify a metadata snapshot associated with the metadata record, the metadata snapshot including a plurality of nodes corresponding to metadata;
establish a time sequence spanning between an arbitrary time reference and a time reference of the metadata snapshot; and
locate a plurality of differential metadata records created during the time sequence, the plurality of differential metadata records each including nodes corresponding to changes in the metadata relative to the first metadata snapshot and one or more empty nodes corresponding to metadata inherited from temporally adjacent differential metadata records or the first metadata snapshot, wherein a node is representative of blocks of data, the node being defined by an offset and a length;
a parsing module adapted to parse the metadata snapshot to determine the nodes and create an index for the metadata record to be restored by:
opening the plurality of differential metadata records simultaneously;
iterating through each of the nodes of the plurality of differential metadata records;
deferring iteration when a node to be inherited by a second differential metadata record occurs before the currently inheriting node of a first differential metadata record temporally adjacent to the second differential metadata record the deferring further including recursively iterating at the currently inheriting node of the first differential metadata record until all nodes of the first differential metadata record have been iterated; and
inheriting the nodes of the first metadata snapshot, utilizing the index, in reverse chronological order relative to the nodes of the plurality of opened differential metadata records to determine changes between the first metadata snapshot and the metadata record to be restored; and
a restoration engine adapted to restore a metadata record to the arbitrary time reference utilizing the determined changes.
9. The system according to claim 8 , wherein the parsing module is adapted to iterate through each of the differential metadata records for each node of the metadata snapshot, wherein a node currently being iterated is available for inheritance through each of the differential metadata record.
10. The system according to claim 8 , wherein if the system is adapted to restore a differential metadata record the file locator module is adapted to:
locate a first metadata snapshot created before the arbitrary time reference and a second metadata snapshot created after the arbitrary time reference; and
establish a time sequence spanning between the creation date of the first metadata snapshot and the creation date of the second metadata snapshot.
11. The system according to claim 8 , wherein when before a node is inherited by a differential metadata record from a metadata snapshot, the parsing module is adapted to synthesize a null node for the metadata snapshot, the null node corresponding to absent nodes in the one or more located differential metadata records.
12. The system according to claim 11 , wherein the parsing module is adapted to synthesize a null node by parsing all nodes of the located differential metadata records prior to the differential metadata record inheriting the node to determine whether a node to be inherited is absent in the located differential metadata records.