// newBlockImporter returns a new importer for the provided file reader seeker
// and database.
func newBlockImporter(db database.DB, r io.ReadSeeker) (*blockImporter, error) {
// Create the transaction and address indexes if needed.
//
// CAUTION: the txindex needs to be first in the indexes array because
// the addrindex uses data from the txindex during catchup. If the
// addrindex is run first, it may not have the transactions from the
// current block indexed.
var indexes []indexers.Indexer
if cfg.TxIndex || cfg.AddrIndex {
// Enable transaction index if address index is enabled since it
// requires it.
if !cfg.TxIndex {
log.Infof("Transaction index enabled because it is " +
"required by the address index")
cfg.TxIndex = true
} else {
log.Info("Transaction index is enabled")
}
indexes = append(indexes, indexers.NewTxIndex(db))
}
if cfg.AddrIndex {
log.Info("Address index is enabled")
indexes = append(indexes, indexers.NewAddrIndex(db, activeNetParams))
}
// Create an index manager if any of the optional indexes are enabled.
var indexManager blockchain.IndexManager
if len(indexes) > 0 {
indexManager = indexers.NewManager(db, indexes)
}
chain, err := blockchain.New(&blockchain.Config{
DB: db,
ChainParams: activeNetParams,
TimeSource: blockchain.NewMedianTime(),
IndexManager: indexManager,
})
if err != nil {
return nil, err
}
return &blockImporter{
db: db,
r: r,
processQueue: make(chan []byte, 2),
doneChan: make(chan bool),
errChan: make(chan error),
quit: make(chan struct{}),
chain: chain,
lastLogTime: time.Now(),
}, nil
}
func main() {
// Load configuration and parse command line.
tcfg, _, err := loadConfig()
if err != nil {
return
}
cfg = tcfg
// Load the block database.
db, err := loadBlockDB()
if err != nil {
fmt.Fprintln(os.Stderr, "failed to load database:", err)
return
}
defer db.Close()
// Setup chain. Ignore notifications since they aren't needed for this
// util.
chain, err := blockchain.New(&blockchain.Config{
DB: db,
ChainParams: activeNetParams,
})
if err != nil {
fmt.Fprintf(os.Stderr, "failed to initialize chain: %v\n", err)
return
}
// Get the latest block hash and height from the database and report
// status.
best := chain.BestSnapshot()
fmt.Printf("Block database loaded with block height %d\n", best.Height)
// Find checkpoint candidates.
candidates, err := findCandidates(chain, best.Hash)
if err != nil {
fmt.Fprintln(os.Stderr, "Unable to identify candidates:", err)
return
}
// No candidates.
if len(candidates) == 0 {
fmt.Println("No candidates found.")
return
}
// Show the candidates.
for i, checkpoint := range candidates {
showCandidate(i+1, checkpoint)
}
}
// This example demonstrates how to create a new chain instance and use
// ProcessBlock to attempt to attempt add a block to the chain. As the package
// overview documentation describes, this includes all of the Bitcoin consensus
// rules. This example intentionally attempts to insert a duplicate genesis
// block to illustrate how an invalid block is handled.
func ExampleBlockChain_ProcessBlock() {
// Create a new database to store the accepted blocks into. Typically
// this would be opening an existing database and would not be deleting
// and creating a new database like this, but it is done here so this is
// a complete working example and does not leave temporary files laying
// around.
dbPath := filepath.Join(os.TempDir(), "exampleprocessblock")
_ = os.RemoveAll(dbPath)
db, err := database.Create("ffldb", dbPath, chaincfg.MainNetParams.Net)
if err != nil {
fmt.Printf("Failed to create database: %v\n", err)
return
}
defer os.RemoveAll(dbPath)
defer db.Close()
// Create a new BlockChain instance using the underlying database for
// the main bitcoin network. This example does not demonstrate some
// of the other available configuration options such as specifying a
// notification callback and signature cache. Also, the caller would
// ordinarily keep a reference to the median time source and add time
// values obtained from other peers on the network so the local time is
// adjusted to be in agreement with other peers.
chain, err := blockchain.New(&blockchain.Config{
DB: db,
ChainParams: &chaincfg.MainNetParams,
TimeSource: blockchain.NewMedianTime(),
})
if err != nil {
fmt.Printf("Failed to create chain instance: %v\n", err)
return
}
// Process a block. For this example, we are going to intentionally
// cause an error by trying to process the genesis block which already
// exists.
genesisBlock := btcutil.NewBlock(chaincfg.MainNetParams.GenesisBlock)
isMainChain, isOrphan, err := chain.ProcessBlock(genesisBlock,
blockchain.BFNone)
if err != nil {
fmt.Printf("Failed to process block: %v\n", err)
return
}
fmt.Printf("Block accepted. Is it on the main chain?: %v", isMainChain)
fmt.Printf("Block accepted. Is it an orphan?: %v", isOrphan)
// Output:
// Failed to process block: already have block 000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f
}
// newBlockManager returns a new bitcoin block manager.
// Use Start to begin processing asynchronous block and inv updates.
func newBlockManager(s *server, indexManager blockchain.IndexManager) (*blockManager, error) {
bm := blockManager{
server: s,
rejectedTxns: make(map[chainhash.Hash]struct{}),
requestedTxns: make(map[chainhash.Hash]struct{}),
requestedBlocks: make(map[chainhash.Hash]struct{}),
progressLogger: newBlockProgressLogger("Processed", bmgrLog),
msgChan: make(chan interface{}, cfg.MaxPeers*3),
headerList: list.New(),
quit: make(chan struct{}),
}
// Create a new block chain instance with the appropriate configuration.
var err error
bm.chain, err = blockchain.New(&blockchain.Config{
DB: s.db,
ChainParams: s.chainParams,
TimeSource: s.timeSource,
Notifications: bm.handleNotifyMsg,
SigCache: s.sigCache,
IndexManager: indexManager,
HashCache: s.hashCache,
})
if err != nil {
return nil, err
}
best := bm.chain.BestSnapshot()
bm.chain.DisableCheckpoints(cfg.DisableCheckpoints)
if !cfg.DisableCheckpoints {
// Initialize the next checkpoint based on the current height.
bm.nextCheckpoint = bm.findNextHeaderCheckpoint(best.Height)
if bm.nextCheckpoint != nil {
bm.resetHeaderState(best.Hash, best.Height)
}
} else {
bmgrLog.Info("Checkpoints are disabled")
}
return &bm, nil
}
// chainSetup is used to create a new db and chain instance with the genesis
// block already inserted. In addition to the new chain instance, it returns
// a teardown function the caller should invoke when done testing to clean up.
func chainSetup(dbName string, params *chaincfg.Params) (*blockchain.BlockChain, func(), error) {
if !isSupportedDbType(testDbType) {
return nil, nil, fmt.Errorf("unsupported db type %v", testDbType)
}
// Handle memory database specially since it doesn't need the disk
// specific handling.
var db database.DB
var teardown func()
if testDbType == "memdb" {
ndb, err := database.Create(testDbType)
if err != nil {
return nil, nil, fmt.Errorf("error creating db: %v", err)
}
db = ndb
// Setup a teardown function for cleaning up. This function is
// returned to the caller to be invoked when it is done testing.
teardown = func() {
db.Close()
}
} else {
// Create the root directory for test databases.
if !fileExists(testDbRoot) {
if err := os.MkdirAll(testDbRoot, 0700); err != nil {
err := fmt.Errorf("unable to create test db "+
"root: %v", err)
return nil, nil, err
}
}
// Create a new database to store the accepted blocks into.
dbPath := filepath.Join(testDbRoot, dbName)
_ = os.RemoveAll(dbPath)
ndb, err := database.Create(testDbType, dbPath, blockDataNet)
if err != nil {
return nil, nil, fmt.Errorf("error creating db: %v", err)
}
db = ndb
// Setup a teardown function for cleaning up. This function is
// returned to the caller to be invoked when it is done testing.
teardown = func() {
db.Close()
os.RemoveAll(dbPath)
os.RemoveAll(testDbRoot)
}
}
// Copy the chain params to ensure any modifications the tests do to
// the chain parameters do not affect the global instance.
paramsCopy := *params
// Create the main chain instance.
chain, err := blockchain.New(&blockchain.Config{
DB: db,
ChainParams: ¶msCopy,
TimeSource: blockchain.NewMedianTime(),
SigCache: txscript.NewSigCache(1000),
})
if err != nil {
teardown()
err := fmt.Errorf("failed to create chain instance: %v", err)
return nil, nil, err
}
return chain, teardown, nil
}
