forked from TrueCloudLab/frostfs-node
8cf71b7f1c
In this commit we implement algorithm for CRDT trees from https://martin.klepmann.com/papers/move-op.pdf Each tree is identified by the ID of a container it belongs to and the tree name itself. Essentially, it is a sequence of operations which should be applied in chronological order to get a usual tree representation. There are 2 backends for now: bbolt database and in-memory. In-memory backend is here for debugging and will eventually act as a memory-cache for the on-disk database. Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>
35 lines
1.4 KiB
Go
35 lines
1.4 KiB
Go
package pilorama
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import cidSDK "github.com/nspcc-dev/neofs-sdk-go/container/id"
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// Forest represents CRDT tree.
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type Forest interface {
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// TreeMove moves node in the tree.
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// If the parent of the move operation is TrashID, the node is removed.
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// If the child of the move operation is RootID, new ID is generated and added to a tree.
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TreeMove(cid cidSDK.ID, treeID string, m *Move) (*LogMove, error)
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// TreeAddByPath adds new node in the tree using provided path.
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// The path is constructed by descending from the root using the values of the attr in meta.
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TreeAddByPath(cid cidSDK.ID, treeID string, attr string, path []string, meta []KeyValue) ([]LogMove, error)
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// TreeApply applies replicated operation from another node.
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TreeApply(cid cidSDK.ID, treeID string, m *Move) error
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// TreeGetByPath returns all nodes corresponding to the path.
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// The path is constructed by descending from the root using the values of the
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// AttributeFilename in meta.
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// The last argument determines whether only the node with the latest timestamp is returned.
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TreeGetByPath(cid cidSDK.ID, treeID string, attr string, path []string, latest bool) ([]Node, error)
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// TreeGetMeta returns meta information of the node with the specified ID.
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TreeGetMeta(cid cidSDK.ID, treeID string, nodeID Node) (Meta, error)
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}
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type ForestStorage interface {
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Init() error
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Open() error
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Close() error
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Forest
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}
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const (
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AttributeFilename = "FileName"
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AttributeVersion = "Version"
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)
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