lotus/lib/blockstore/memstore.go

91 lines
2.0 KiB
Go

package blockstore
import (
"context"
blocks "github.com/ipfs/go-block-format"
"github.com/ipfs/go-cid"
)
// MemStore is a terminal blockstore that keeps blocks in memory.
type MemStore map[cid.Cid]blocks.Block
func (m MemStore) DeleteBlock(k cid.Cid) error {
delete(m, k)
return nil
}
func (m MemStore) Has(k cid.Cid) (bool, error) {
_, ok := m[k]
return ok, nil
}
func (m MemStore) View(k cid.Cid, callback func([]byte) error) error {
b, ok := m[k]
if !ok {
return ErrNotFound
}
return callback(b.RawData())
}
func (m MemStore) Get(k cid.Cid) (blocks.Block, error) {
b, ok := m[k]
if !ok {
return nil, ErrNotFound
}
return b, nil
}
// GetSize returns the CIDs mapped BlockSize
func (m MemStore) GetSize(k cid.Cid) (int, error) {
b, ok := m[k]
if !ok {
return 0, ErrNotFound
}
return len(b.RawData()), nil
}
// Put puts a given block to the underlying datastore
func (m MemStore) Put(b blocks.Block) error {
// Convert to a basic block for safety, but try to reuse the existing
// block if it's already a basic block.
k := b.Cid()
if _, ok := b.(*blocks.BasicBlock); !ok {
// If we already have the block, abort.
if _, ok := m[k]; ok {
return nil
}
// the error is only for debugging.
b, _ = blocks.NewBlockWithCid(b.RawData(), b.Cid())
}
m[b.Cid()] = b
return nil
}
// PutMany puts a slice of blocks at the same time using batching
// capabilities of the underlying datastore whenever possible.
func (m MemStore) PutMany(bs []blocks.Block) error {
for _, b := range bs {
_ = m.Put(b) // can't fail
}
return nil
}
// AllKeysChan returns a channel from which
// the CIDs in the Blockstore can be read. It should respect
// the given context, closing the channel if it becomes Done.
func (m MemStore) AllKeysChan(ctx context.Context) (<-chan cid.Cid, error) {
ch := make(chan cid.Cid, len(m))
for k := range m {
ch <- k
}
close(ch)
return ch, nil
}
// HashOnRead specifies if every read block should be
// rehashed to make sure it matches its CID.
func (m MemStore) HashOnRead(enabled bool) {
// no-op
}