swarm/storage/localstore: new localstore package (#19015)

swarm/storage/localstore/mode_put.go

@@ -0,0 +1,160 @@
+// Copyright 2018 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package localstore
+
+import (
+	"github.com/ethereum/go-ethereum/swarm/shed"
+	"github.com/ethereum/go-ethereum/swarm/storage"
+	"github.com/syndtr/goleveldb/leveldb"
+)
+
+// ModePut enumerates different Putter modes.
+type ModePut int
+
+// Putter modes.
+const (
+	// ModePutRequest: when a chunk is received as a result of retrieve request and delivery
+	ModePutRequest ModePut = iota
+	// ModePutSync: when a chunk is received via syncing
+	ModePutSync
+	// ModePutUpload: when a chunk is created by local upload
+	ModePutUpload
+)
+
+// Putter provides Put method to store Chunks
+// to database.
+type Putter struct {
+	db   *DB
+	mode ModePut
+}
+
+// NewPutter returns a new Putter on database
+// with a specific Mode.
+func (db *DB) NewPutter(mode ModePut) *Putter {
+	return &Putter{
+		mode: mode,
+		db:   db,
+	}
+}
+
+// Put stores the Chunk to database and depending
+// on the Putter mode, it updates required indexes.
+func (p *Putter) Put(ch storage.Chunk) (err error) {
+	return p.db.put(p.mode, chunkToItem(ch))
+}
+
+// put stores Item to database and updates other
+// indexes. It acquires lockAddr to protect two calls
+// of this function for the same address in parallel.
+// Item fields Address and Data must not be
+// with their nil values.
+func (db *DB) put(mode ModePut, item shed.Item) (err error) {
+	// protect parallel updates
+	unlock, err := db.lockAddr(item.Address)
+	if err != nil {
+		return err
+	}
+	defer unlock()
+
+	batch := new(leveldb.Batch)
+
+	// variables that provide information for operations
+	// to be done after write batch function successfully executes
+	var gcSizeChange int64   // number to add or subtract from gcSize
+	var triggerPullFeed bool // signal pull feed subscriptions to iterate
+	var triggerPushFeed bool // signal push feed subscriptions to iterate
+
+	switch mode {
+	case ModePutRequest:
+		// put to indexes: retrieve, gc; it does not enter the syncpool
+
+		// check if the chunk already is in the database
+		// as gc index is updated
+		i, err := db.retrievalAccessIndex.Get(item)
+		switch err {
+		case nil:
+			item.AccessTimestamp = i.AccessTimestamp
+		case leveldb.ErrNotFound:
+			// no chunk accesses
+		default:
+			return err
+		}
+		i, err = db.retrievalDataIndex.Get(item)
+		switch err {
+		case nil:
+			item.StoreTimestamp = i.StoreTimestamp
+		case leveldb.ErrNotFound:
+			// no chunk accesses
+		default:
+			return err
+		}
+		if item.AccessTimestamp != 0 {
+			// delete current entry from the gc index
+			db.gcIndex.DeleteInBatch(batch, item)
+			gcSizeChange--
+		}
+		if item.StoreTimestamp == 0 {
+			item.StoreTimestamp = now()
+		}
+		// update access timestamp
+		item.AccessTimestamp = now()
+		// update retrieve access index
+		db.retrievalAccessIndex.PutInBatch(batch, item)
+		// add new entry to gc index
+		db.gcIndex.PutInBatch(batch, item)
+		db.gcUncountedHashesIndex.PutInBatch(batch, item)
+		gcSizeChange++
+
+		db.retrievalDataIndex.PutInBatch(batch, item)
+
+	case ModePutUpload:
+		// put to indexes: retrieve, push, pull
+
+		item.StoreTimestamp = now()
+		db.retrievalDataIndex.PutInBatch(batch, item)
+		db.pullIndex.PutInBatch(batch, item)
+		triggerPullFeed = true
+		db.pushIndex.PutInBatch(batch, item)
+		triggerPushFeed = true
+
+	case ModePutSync:
+		// put to indexes: retrieve, pull
+
+		item.StoreTimestamp = now()
+		db.retrievalDataIndex.PutInBatch(batch, item)
+		db.pullIndex.PutInBatch(batch, item)
+		triggerPullFeed = true
+
+	default:
+		return ErrInvalidMode
+	}
+
+	err = db.shed.WriteBatch(batch)
+	if err != nil {
+		return err
+	}
+	if gcSizeChange != 0 {
+		db.incGCSize(gcSizeChange)
+	}
+	if triggerPullFeed {
+		db.triggerPullSubscriptions(db.po(item.Address))
+	}
+	if triggerPushFeed {
+		db.triggerPushSubscriptions()
+	}
+	return nil
+}