Merge pull request #14785 from Arachnid/downloaddb

cmd: Added support for downloading to another DB instance

4 files changed, 243 insertions, 8 deletions

diff --git a/cmd/geth/chaincmd.go b/cmd/geth/chaincmd.go
index 12bc1d7c6..4a9a7b11b 100644
--- a/cmd/geth/chaincmd.go
+++ b/cmd/geth/chaincmd.go
@@ -31,7 +31,9 @@ import (
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/eth/downloader"
 	"github.com/ethereum/go-ethereum/ethdb"
+	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/trie"
 	"github.com/syndtr/goleveldb/leveldb/util"
@@ -71,7 +73,7 @@ It expects the genesis file as argument.`,
 The import command imports blocks from an RLP-encoded form. The form can be one file
 with several RLP-encoded blocks, or several files can be used.
 
-If only one file is used, import error will result in failure. If several files are used, 
+If only one file is used, import error will result in failure. If several files are used,
 processing will proceed even if an individual RLP-file import failure occurs.`,
 	}
 	exportCommand = cli.Command{
@@ -91,6 +93,23 @@ Optional second and third arguments control the first and
 last block to write. In this mode, the file will be appended
 if already existing.`,
 	}
+	copydbCommand = cli.Command{
+		Action:    utils.MigrateFlags(copyDb),
+		Name:      "copydb",
+		Usage:     "Create a local chain from a target chaindata folder",
+		ArgsUsage: "<sourceChaindataDir>",
+		Flags: []cli.Flag{
+			utils.DataDirFlag,
+			utils.CacheFlag,
+			utils.SyncModeFlag,
+			utils.FakePoWFlag,
+			utils.TestnetFlag,
+			utils.RinkebyFlag,
+		},
+		Category: "BLOCKCHAIN COMMANDS",
+		Description: `
+The first argument must be the directory containing the blockchain to download from`,
+	}
 	removedbCommand = cli.Command{
 		Action:    utils.MigrateFlags(removeDB),
 		Name:      "removedb",
@@ -268,6 +287,54 @@ func exportChain(ctx *cli.Context) error {
 	return nil
 }
 
+func copyDb(ctx *cli.Context) error {
+	// Ensure we have a source chain directory to copy
+	if len(ctx.Args()) != 1 {
+		utils.Fatalf("Source chaindata directory path argument missing")
+	}
+	// Initialize a new chain for the running node to sync into
+	stack := makeFullNode(ctx)
+	chain, chainDb := utils.MakeChain(ctx, stack)
+
+	syncmode := *utils.GlobalTextMarshaler(ctx, utils.SyncModeFlag.Name).(*downloader.SyncMode)
+	dl := downloader.New(syncmode, chainDb, new(event.TypeMux), chain, nil, nil)
+
+	// Create a source peer to satisfy downloader requests from
+	db, err := ethdb.NewLDBDatabase(ctx.Args().First(), ctx.GlobalInt(utils.CacheFlag.Name), 256)
+	if err != nil {
+		return err
+	}
+	hc, err := core.NewHeaderChain(db, chain.Config(), chain.Engine(), func() bool { return false })
+	if err != nil {
+		return err
+	}
+	peer := downloader.NewFakePeer("local", db, hc, dl)
+	if err = dl.RegisterPeer("local", 63, peer); err != nil {
+		return err
+	}
+	// Synchronise with the simulated peer
+	start := time.Now()
+
+	currentHeader := hc.CurrentHeader()
+	if err = dl.Synchronise("local", currentHeader.Hash(), hc.GetTd(currentHeader.Hash(), currentHeader.Number.Uint64()), syncmode); err != nil {
+		return err
+	}
+	for dl.Synchronising() {
+		time.Sleep(10 * time.Millisecond)
+	}
+	fmt.Printf("Database copy done in %v\n", time.Since(start))
+
+	// Compact the entire database to remove any sync overhead
+	start = time.Now()
+	fmt.Println("Compacting entire database...")
+	if err = chainDb.(*ethdb.LDBDatabase).LDB().CompactRange(util.Range{}); err != nil {
+		utils.Fatalf("Compaction failed: %v", err)
+	}
+	fmt.Printf("Compaction done in %v.\n\n", time.Since(start))
+
+	return nil
+}
+
 func removeDB(ctx *cli.Context) error {
 	stack, _ := makeConfigNode(ctx)
 
diff --git a/cmd/geth/main.go b/cmd/geth/main.go
index 8166c9ce8..88f3528f3 100644
--- a/cmd/geth/main.go
+++ b/cmd/geth/main.go
@@ -146,6 +146,7 @@ func init() {
 		initCommand,
 		importCommand,
 		exportCommand,
+		copydbCommand,
 		removedbCommand,
 		dumpCommand,
 		// See monitorcmd.go:
diff --git a/cmd/utils/flags.go b/cmd/utils/flags.go
index a62b4940b..bfef619f6 100644
--- a/cmd/utils/flags.go
+++ b/cmd/utils/flags.go
@@ -31,6 +31,8 @@ import (
 	"github.com/ethereum/go-ethereum/accounts"
 	"github.com/ethereum/go-ethereum/accounts/keystore"
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/consensus"
+	"github.com/ethereum/go-ethereum/consensus/clique"
 	"github.com/ethereum/go-ethereum/consensus/ethash"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/state"
@@ -1086,17 +1088,22 @@ func MakeChain(ctx *cli.Context, stack *node.Node) (chain *core.BlockChain, chai
 	var err error
 	chainDb = MakeChainDatabase(ctx, stack)
 
-	engine := ethash.NewFaker()
-	if !ctx.GlobalBool(FakePoWFlag.Name) {
-		engine = ethash.New(
-			stack.ResolvePath(eth.DefaultConfig.EthashCacheDir), eth.DefaultConfig.EthashCachesInMem, eth.DefaultConfig.EthashCachesOnDisk,
-			stack.ResolvePath(eth.DefaultConfig.EthashDatasetDir), eth.DefaultConfig.EthashDatasetsInMem, eth.DefaultConfig.EthashDatasetsOnDisk,
-		)
-	}
 	config, _, err := core.SetupGenesisBlock(chainDb, MakeGenesis(ctx))
 	if err != nil {
 		Fatalf("%v", err)
 	}
+	var engine consensus.Engine
+	if config.Clique != nil {
+		engine = clique.New(config.Clique, chainDb)
+	} else {
+		engine = ethash.NewFaker()
+		if !ctx.GlobalBool(FakePoWFlag.Name) {
+			engine = ethash.New(
+				stack.ResolvePath(eth.DefaultConfig.EthashCacheDir), eth.DefaultConfig.EthashCachesInMem, eth.DefaultConfig.EthashCachesOnDisk,
+				stack.ResolvePath(eth.DefaultConfig.EthashDatasetDir), eth.DefaultConfig.EthashDatasetsInMem, eth.DefaultConfig.EthashDatasetsOnDisk,
+			)
+		}
+	}
 	vmcfg := vm.Config{EnablePreimageRecording: ctx.GlobalBool(VMEnableDebugFlag.Name)}
 	chain, err = core.NewBlockChain(chainDb, config, engine, vmcfg)
 	if err != nil {
diff --git a/eth/downloader/fakepeer.go b/eth/downloader/fakepeer.go
new file mode 100644
index 000000000..ebdb9c334
--- /dev/null
+++ b/eth/downloader/fakepeer.go
@@ -0,0 +1,160 @@
+// Copyright 2017 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 downloader
+
+import (
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/ethdb"
+)
+
+// FakePeer is a mock downloader peer that operates on a local database instance
+// instead of being an actual live node. It's useful for testing and to implement
+// sync commands from an xisting local database.
+type FakePeer struct {
+	id string
+	db ethdb.Database
+	hc *core.HeaderChain
+	dl *Downloader
+}
+
+// NewFakePeer creates a new mock downloader peer with the given data sources.
+func NewFakePeer(id string, db ethdb.Database, hc *core.HeaderChain, dl *Downloader) *FakePeer {
+	return &FakePeer{id: id, db: db, hc: hc, dl: dl}
+}
+
+// Head implements downloader.Peer, returning the current head hash and number
+// of the best known header.
+func (p *FakePeer) Head() (common.Hash, *big.Int) {
+	header := p.hc.CurrentHeader()
+	return header.Hash(), header.Number
+}
+
+// RequestHeadersByHash implements downloader.Peer, returning a batch of headers
+// defined by the origin hash and the associaed query parameters.
+func (p *FakePeer) RequestHeadersByHash(hash common.Hash, amount int, skip int, reverse bool) error {
+	var (
+		headers []*types.Header
+		unknown bool
+	)
+	for !unknown && len(headers) < amount {
+		origin := p.hc.GetHeaderByHash(hash)
+		if origin == nil {
+			break
+		}
+		number := origin.Number.Uint64()
+		headers = append(headers, origin)
+		if reverse {
+			for i := 0; i < int(skip)+1; i++ {
+				if header := p.hc.GetHeader(hash, number); header != nil {
+					hash = header.ParentHash
+					number--
+				} else {
+					unknown = true
+					break
+				}
+			}
+		} else {
+			var (
+				current = origin.Number.Uint64()
+				next    = current + uint64(skip) + 1
+			)
+			if header := p.hc.GetHeaderByNumber(next); header != nil {
+				if p.hc.GetBlockHashesFromHash(header.Hash(), uint64(skip+1))[skip] == hash {
+					hash = header.Hash()
+				} else {
+					unknown = true
+				}
+			} else {
+				unknown = true
+			}
+		}
+	}
+	p.dl.DeliverHeaders(p.id, headers)
+	return nil
+}
+
+// RequestHeadersByNumber implements downloader.Peer, returning a batch of headers
+// defined by the origin number and the associaed query parameters.
+func (p *FakePeer) RequestHeadersByNumber(number uint64, amount int, skip int, reverse bool) error {
+	var (
+		headers []*types.Header
+		unknown bool
+	)
+	for !unknown && len(headers) < amount {
+		origin := p.hc.GetHeaderByNumber(number)
+		if origin == nil {
+			break
+		}
+		if reverse {
+			if number >= uint64(skip+1) {
+				number -= uint64(skip + 1)
+			} else {
+				unknown = true
+			}
+		} else {
+			number += uint64(skip + 1)
+		}
+		headers = append(headers, origin)
+	}
+	p.dl.DeliverHeaders(p.id, headers)
+	return nil
+}
+
+// RequestBodies implements downloader.Peer, returning a batch of block bodies
+// corresponding to the specified block hashes.
+func (p *FakePeer) RequestBodies(hashes []common.Hash) error {
+	var (
+		txs    [][]*types.Transaction
+		uncles [][]*types.Header
+	)
+	for _, hash := range hashes {
+		block := core.GetBlock(p.db, hash, p.hc.GetBlockNumber(hash))
+
+		txs = append(txs, block.Transactions())
+		uncles = append(uncles, block.Uncles())
+	}
+	p.dl.DeliverBodies(p.id, txs, uncles)
+	return nil
+}
+
+// RequestReceipts implements downloader.Peer, returning a batch of transaction
+// receipts corresponding to the specified block hashes.
+func (p *FakePeer) RequestReceipts(hashes []common.Hash) error {
+	var receipts [][]*types.Receipt
+	for _, hash := range hashes {
+		receipts = append(receipts, core.GetBlockReceipts(p.db, hash, p.hc.GetBlockNumber(hash)))
+	}
+	p.dl.DeliverReceipts(p.id, receipts)
+	return nil
+}
+
+// RequestNodeData implements downloader.Peer, returning a batch of state trie
+// nodes corresponding to the specified trie hashes.
+func (p *FakePeer) RequestNodeData(hashes []common.Hash) error {
+	var data [][]byte
+	for _, hash := range hashes {
+		if entry, err := p.db.Get(hash.Bytes()); err == nil {
+			data = append(data, entry)
+		}
+	}
+	p.dl.DeliverNodeData(p.id, data)
+	return nil
+}