lotus/blockstore/blockstore.go
2022-06-14 17:00:51 +02:00

127 lines
3.5 KiB
Go

package blockstore
import (
"context"
cid "github.com/ipfs/go-cid"
ds "github.com/ipfs/go-datastore"
blockstore "github.com/ipfs/go-ipfs-blockstore"
logging "github.com/ipfs/go-log/v2"
)
var log = logging.Logger("blockstore")
var ErrNotFound = blockstore.ErrNotFound
// Blockstore is the blockstore interface used by Lotus. It is the union
// of the basic go-ipfs blockstore, with other capabilities required by Lotus,
// e.g. View or Sync.
type Blockstore interface {
blockstore.Blockstore
blockstore.Viewer
BatchDeleter
}
// BasicBlockstore is an alias to the original IPFS Blockstore.
type BasicBlockstore = blockstore.Blockstore
type Viewer = blockstore.Viewer
type BatchDeleter interface {
DeleteMany(ctx context.Context, cids []cid.Cid) error
}
// BlockstoreIterator is a trait for efficient iteration
type BlockstoreIterator interface {
ForEachKey(func(cid.Cid) error) error
}
// BlockstoreGC is a trait for blockstores that support online garbage collection
type BlockstoreGC interface {
CollectGarbage(options ...BlockstoreGCOption) error
}
// BlockstoreGCOption is a functional interface for controlling blockstore GC options
type BlockstoreGCOption = func(*BlockstoreGCOptions) error
// BlockstoreGCOptions is a struct with GC options
type BlockstoreGCOptions struct {
FullGC bool
}
func WithFullGC(fullgc bool) BlockstoreGCOption {
return func(opts *BlockstoreGCOptions) error {
opts.FullGC = fullgc
return nil
}
}
// BlockstoreSize is a trait for on-disk blockstores that can report their size
type BlockstoreSize interface {
Size() (int64, error)
}
// WrapIDStore wraps the underlying blockstore in an "identity" blockstore.
// The ID store filters out all puts for blocks with CIDs using the "identity"
// hash function. It also extracts inlined blocks from CIDs using the identity
// hash function and returns them on get/has, ignoring the contents of the
// blockstore.
func WrapIDStore(bstore blockstore.Blockstore) Blockstore {
if is, ok := bstore.(*idstore); ok {
// already wrapped
return is
}
if bs, ok := bstore.(Blockstore); ok {
// we need to wrap our own because we don't want to neuter the DeleteMany method
// the underlying blockstore has implemented an (efficient) DeleteMany
return NewIDStore(bs)
}
// The underlying blockstore does not implement DeleteMany, so we need to shim it.
// This is less efficient as it'll iterate and perform single deletes.
return NewIDStore(Adapt(bstore))
}
// FromDatastore creates a new blockstore backed by the given datastore.
func FromDatastore(dstore ds.Batching) Blockstore {
return WrapIDStore(blockstore.NewBlockstore(dstore))
}
type adaptedBlockstore struct {
blockstore.Blockstore
}
var _ Blockstore = (*adaptedBlockstore)(nil)
func (a *adaptedBlockstore) View(ctx context.Context, cid cid.Cid, callback func([]byte) error) error {
blk, err := a.Get(ctx, cid)
if err != nil {
return err
}
return callback(blk.RawData())
}
func (a *adaptedBlockstore) DeleteMany(ctx context.Context, cids []cid.Cid) error {
for _, cid := range cids {
err := a.DeleteBlock(ctx, cid)
if err != nil {
return err
}
}
return nil
}
// Adapt adapts a standard blockstore to a Lotus blockstore by
// enriching it with the extra methods that Lotus requires (e.g. View, Sync).
//
// View proxies over to Get and calls the callback with the value supplied by Get.
// Sync noops.
func Adapt(bs blockstore.Blockstore) Blockstore {
if ret, ok := bs.(Blockstore); ok {
return ret
}
return &adaptedBlockstore{bs}
}