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>
48 lines
810 B
Go
48 lines
810 B
Go
package pilorama
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import "github.com/nspcc-dev/neo-go/pkg/io"
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func (x *Meta) FromBytes(data []byte) error {
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if len(data) == 0 {
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x.Items = nil
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x.Time = 0
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return nil
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}
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r := io.NewBinReaderFromBuf(data)
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ts := r.ReadVarUint()
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size := r.ReadVarUint()
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m := make([]KeyValue, size)
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for i := range m {
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m[i].Key = r.ReadString()
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m[i].Value = r.ReadVarBytes()
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}
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if r.Err != nil {
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return r.Err
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}
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x.Time = ts
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x.Items = m
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return nil
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}
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func (x Meta) Bytes() []byte {
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w := io.NewBufBinWriter()
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w.WriteVarUint(x.Time)
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w.WriteVarUint(uint64(len(x.Items)))
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for _, e := range x.Items {
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w.WriteString(e.Key)
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w.WriteVarBytes(e.Value)
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}
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return w.Bytes()
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}
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func (x Meta) GetAttr(name string) []byte {
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for _, kv := range x.Items {
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if kv.Key == name {
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return kv.Value
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}
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}
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return nil
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}
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