github.com/hasnat/dolt/go@v0.0.0-20210628190320-9eb5d843fbb7/libraries/doltcore/remotestorage/chunk_cache.go (about)

     1  // Copyright 2019 Dolthub, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package remotestorage
    16  
    17  import (
    18  	"github.com/dolthub/dolt/go/store/hash"
    19  	"github.com/dolthub/dolt/go/store/nbs"
    20  )
    21  
    22  // ChunkCache is an interface used for caching chunks
    23  type ChunkCache interface {
    24  	// Put puts a slice of chunks into the cache.
    25  	Put(c []nbs.CompressedChunk)
    26  
    27  	// Get gets a map of hash to chunk for a set of hashes.  In the event that a chunk is not in the cache, chunks.Empty.
    28  	// is put in it's place
    29  	Get(h hash.HashSet) map[hash.Hash]nbs.CompressedChunk
    30  
    31  	// Has takes a set of hashes and returns the set of hashes that the cache currently does not have in it.
    32  	Has(h hash.HashSet) (absent hash.HashSet)
    33  
    34  	// PutChunk puts a single chunk in the cache.  true returns in the event that the chunk was cached successfully
    35  	// and false is returned if that chunk is already is the cache.
    36  	PutChunk(chunk nbs.CompressedChunk) bool
    37  
    38  	// GetAndClearChunksToFlush gets a map of hash to chunk which includes all the chunks that were put in the cache
    39  	// between the last time GetAndClearChunksToFlush was called and now.
    40  	GetAndClearChunksToFlush() map[hash.Hash]nbs.CompressedChunk
    41  }