// This example demonstrates creating a new database and inserting the genesis
// block into it.
func ExampleCreateDB() {
// Notice in these example imports that the memdb driver is loaded.
// Ordinarily this would be whatever driver(s) your application
// requires.
// import (
// "github.com/chrjen/btcd/database"
// _ "github.com/chrjen/btcd/database/memdb"
// )
// Create a database and schedule it to be closed on exit. This example
// uses a memory-only database to avoid needing to write anything to
// the disk. Typically, you would specify a persistent database driver
// such as "leveldb" and give it a database name as the second
// parameter.
db, err := database.CreateDB("memdb")
if err != nil {
fmt.Println(err)
return
}
defer db.Close()
// Insert the main network genesis block.
genesis := btcutil.NewBlock(chaincfg.MainNetParams.GenesisBlock)
newHeight, err := db.InsertBlock(genesis)
if err != nil {
fmt.Println(err)
return
}
fmt.Println("New height:", newHeight)
// Output:
// New height: 0
}
// BenchmarkIsCoinBase performs a simple benchmark against the IsCoinBase
// function.
func BenchmarkIsCoinBase(b *testing.B) {
tx, _ := btcutil.NewBlock(&Block100000).Tx(1)
b.ResetTimer()
for i := 0; i < b.N; i++ {
blockchain.IsCoinBase(tx)
}
}
// TestMerkle tests the BuildMerkleTreeStore API.
func TestMerkle(t *testing.T) {
block := btcutil.NewBlock(&Block100000)
merkles := blockchain.BuildMerkleTreeStore(block.Transactions())
calculatedMerkleRoot := merkles[len(merkles)-1]
wantMerkle := &Block100000.Header.MerkleRoot
if !wantMerkle.IsEqual(calculatedMerkleRoot) {
t.Errorf("BuildMerkleTreeStore: merkle root mismatch - "+
"got %v, want %v", calculatedMerkleRoot, wantMerkle)
}
}
// exampleLoadDB is used in the example to elide the setup code.
func exampleLoadDB() (database.Db, error) {
db, err := database.CreateDB("memdb")
if err != nil {
return nil, err
}
// Insert the main network genesis block.
genesis := btcutil.NewBlock(chaincfg.MainNetParams.GenesisBlock)
_, err = db.InsertBlock(genesis)
if err != nil {
return nil, err
}
return db, err
}
// FetchBlockBySha returns a btcutil.Block. The implementation may cache the
// underlying data if desired. This is part of the database.Db interface
// implementation.
//
// This implementation does not use any additional cache since the entire
// database is already in memory.
func (db *MemDb) FetchBlockBySha(sha *wire.ShaHash) (*btcutil.Block, error) {
db.Lock()
defer db.Unlock()
if db.closed {
return nil, ErrDbClosed
}
if blockHeight, exists := db.blocksBySha[*sha]; exists {
block := btcutil.NewBlock(db.blocks[int(blockHeight)])
block.SetHeight(blockHeight)
return block, nil
}
return nil, fmt.Errorf("block %v is not in database", sha)
}
// 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 use memdb
// which is a memory-only database backend, but we create a new db
// here so this is a complete working example.
db, err := database.CreateDB("memdb")
if err != nil {
fmt.Printf("Failed to create database: %v\n", err)
return
}
defer db.Close()
// Insert the main network genesis block. This is part of the initial
// database setup. Like above, this typically would not be needed when
// opening an existing database.
genesisBlock := btcutil.NewBlock(chaincfg.MainNetParams.GenesisBlock)
_, err = db.InsertBlock(genesisBlock)
if err != nil {
fmt.Printf("Failed to insert genesis block: %v\n", err)
return
}
// Create a new BlockChain instance without an initialized signature
// verification cache, using the underlying database for the main
// bitcoin network and ignore notifications.
chain := blockchain.New(db, &chaincfg.MainNetParams, nil, nil)
// Create a new median time source that is required by the upcoming
// call to ProcessBlock. Ordinarily this would also add time values
// obtained from other peers on the network so the local time is
// adjusted to be in agreement with other peers.
timeSource := blockchain.NewMedianTime()
// Process a block. For this example, we are going to intentionally
// cause an error by trying to process the genesis block which already
// exists.
isOrphan, err := chain.ProcessBlock(genesisBlock, timeSource, blockchain.BFNone)
if err != nil {
fmt.Printf("Failed to process block: %v\n", err)
return
}
fmt.Printf("Block accepted. Is it an orphan?: %v", isOrphan)
// Output:
// Failed to process block: already have block 000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f
}
// TestCheckBlockSanity tests the CheckBlockSanity function to ensure it works
// as expected.
func TestCheckBlockSanity(t *testing.T) {
powLimit := chaincfg.MainNetParams.PowLimit
block := btcutil.NewBlock(&Block100000)
timeSource := blockchain.NewMedianTime()
err := blockchain.CheckBlockSanity(block, powLimit, timeSource)
if err != nil {
t.Errorf("CheckBlockSanity: %v", err)
}
// Ensure a block that has a timestamp with a precision higher than one
// second fails.
timestamp := block.MsgBlock().Header.Timestamp
block.MsgBlock().Header.Timestamp = timestamp.Add(time.Nanosecond)
err = blockchain.CheckBlockSanity(block, powLimit, timeSource)
if err == nil {
t.Errorf("CheckBlockSanity: error is nil when it shouldn't be")
}
}
// setupDB is used to create a new db instance with the genesis block already
// inserted. In addition to the new db instance, it returns a teardown function
// the caller should invoke when done testing to clean up.
func setupDB(dbType, dbName string) (database.Db, func(), error) {
db, teardown, err := createDB(dbType, dbName, true)
if err != nil {
return nil, nil, err
}
// Insert the main network genesis block. This is part of the initial
// database setup.
genesisBlock := btcutil.NewBlock(chaincfg.MainNetParams.GenesisBlock)
_, err = db.InsertBlock(genesisBlock)
if err != nil {
teardown()
err := fmt.Errorf("failed to insert genesis block: %v", err)
return nil, nil, err
}
return db, teardown, nil
}
// BenchmarkBlockHeader benchmarks how long it takes to load the mainnet genesis
// block.
func BenchmarkBlock(b *testing.B) {
// Start by creating a new database and populating it with the mainnet
// genesis block.
dbPath := filepath.Join(os.TempDir(), "ffldb-benchblk")
_ = os.RemoveAll(dbPath)
db, err := database.Create("ffldb", dbPath, blockDataNet)
if err != nil {
b.Fatal(err)
}
defer os.RemoveAll(dbPath)
defer db.Close()
err = db.Update(func(tx database.Tx) error {
block := btcutil.NewBlock(chaincfg.MainNetParams.GenesisBlock)
if err := tx.StoreBlock(block); err != nil {
return err
}
return nil
})
if err != nil {
b.Fatal(err)
}
b.ReportAllocs()
b.ResetTimer()
err = db.View(func(tx database.Tx) error {
blockHash := chaincfg.MainNetParams.GenesisHash
for i := 0; i < b.N; i++ {
_, err := tx.FetchBlock(blockHash)
if err != nil {
return err
}
}
return nil
})
if err != nil {
b.Fatal(err)
}
// Don't benchmark teardown.
b.StopTimer()
}
// TestCheckConnectBlock tests the CheckConnectBlock function to ensure it
// fails
func TestCheckConnectBlock(t *testing.T) {
// Create a new database and chain instance to run tests against.
chain, teardownFunc, err := chainSetup("checkconnectblock")
if err != nil {
t.Errorf("Failed to setup chain instance: %v", err)
return
}
defer teardownFunc()
err = chain.GenerateInitialIndex()
if err != nil {
t.Errorf("GenerateInitialIndex: %v", err)
}
// The genesis block should fail to connect since it's already
// inserted.
genesisBlock := chaincfg.MainNetParams.GenesisBlock
err = chain.CheckConnectBlock(btcutil.NewBlock(genesisBlock))
if err == nil {
t.Errorf("CheckConnectBlock: Did not received expected error")
}
}
// UpdateExtraNonce updates the extra nonce in the coinbase script of the passed
// block by regenerating the coinbase script with the passed value and block
// height. It also recalculates and updates the new merkle root that results
// from changing the coinbase script.
func UpdateExtraNonce(msgBlock *wire.MsgBlock, blockHeight int32, extraNonce uint64) error {
coinbaseScript, err := standardCoinbaseScript(blockHeight, extraNonce)
if err != nil {
return err
}
if len(coinbaseScript) > blockchain.MaxCoinbaseScriptLen {
return fmt.Errorf("coinbase transaction script length "+
"of %d is out of range (min: %d, max: %d)",
len(coinbaseScript), blockchain.MinCoinbaseScriptLen,
blockchain.MaxCoinbaseScriptLen)
}
msgBlock.Transactions[0].TxIn[0].SignatureScript = coinbaseScript
// TODO(davec): A btcutil.Block should use saved in the state to avoid
// recalculating all of the other transaction hashes.
// block.Transactions[0].InvalidateCache()
// Recalculate the merkle root with the updated extra nonce.
block := btcutil.NewBlock(msgBlock)
merkles := blockchain.BuildMerkleTreeStore(block.Transactions())
msgBlock.Header.MerkleRoot = *merkles[len(merkles)-1]
return nil
}
// NewBlockTemplate returns a new block template that is ready to be solved
// using the transactions from the passed transaction source pool and a coinbase
// that either pays to the passed address if it is not nil, or a coinbase that
// is redeemable by anyone if the passed address is nil. The nil address
// functionality is useful since there are cases such as the getblocktemplate
// RPC where external mining software is responsible for creating their own
// coinbase which will replace the one generated for the block template. Thus
// the need to have configured address can be avoided.
//
// The transactions selected and included are prioritized according to several
// factors. First, each transaction has a priority calculated based on its
// value, age of inputs, and size. Transactions which consist of larger
// amounts, older inputs, and small sizes have the highest priority. Second, a
// fee per kilobyte is calculated for each transaction. Transactions with a
// higher fee per kilobyte are preferred. Finally, the block generation related
// policy settings are all taken into account.
//
// Transactions which only spend outputs from other transactions already in the
// block chain are immediately added to a priority queue which either
// prioritizes based on the priority (then fee per kilobyte) or the fee per
// kilobyte (then priority) depending on whether or not the BlockPrioritySize
// policy setting allots space for high-priority transactions. Transactions
// which spend outputs from other transactions in the source pool are added to a
// dependency map so they can be added to the priority queue once the
// transactions they depend on have been included.
//
// Once the high-priority area (if configured) has been filled with
// transactions, or the priority falls below what is considered high-priority,
// the priority queue is updated to prioritize by fees per kilobyte (then
// priority).
//
// When the fees per kilobyte drop below the TxMinFreeFee policy setting, the
// transaction will be skipped unless the BlockMinSize policy setting is
// nonzero, in which case the block will be filled with the low-fee/free
// transactions until the block size reaches that minimum size.
//
// Any transactions which would cause the block to exceed the BlockMaxSize
// policy setting, exceed the maximum allowed signature operations per block, or
// otherwise cause the block to be invalid are skipped.
//
// Given the above, a block generated by this function is of the following form:
//
// ----------------------------------- -- --
// | Coinbase Transaction | | |
// |-----------------------------------| | |
// | | | | ----- policy.BlockPrioritySize
// | High-priority Transactions | | |
// | | | |
// |-----------------------------------| | --
// | | |
// | | |
// | | |--- policy.BlockMaxSize
// | Transactions prioritized by fee | |
// | until <= policy.TxMinFreeFee | |
// | | |
// | | |
// | | |
// |-----------------------------------| |
// | Low-fee/Non high-priority (free) | |
// | transactions (while block size | |
// | <= policy.BlockMinSize) | |
// ----------------------------------- --
func NewBlockTemplate(policy *mining.Policy, server *server, payToAddress btcutil.Address) (*BlockTemplate, error) {
var txSource mining.TxSource = server.txMemPool
blockManager := server.blockManager
timeSource := server.timeSource
chainState := &blockManager.chainState
// Extend the most recently known best block.
chainState.Lock()
prevHash := chainState.newestHash
nextBlockHeight := chainState.newestHeight + 1
chainState.Unlock()
// Create a standard coinbase transaction paying to the provided
// address. NOTE: The coinbase value will be updated to include the
// fees from the selected transactions later after they have actually
// been selected. It is created here to detect any errors early
// before potentially doing a lot of work below. The extra nonce helps
// ensure the transaction is not a duplicate transaction (paying the
// same value to the same public key address would otherwise be an
// identical transaction for block version 1).
extraNonce := uint64(0)
coinbaseScript, err := standardCoinbaseScript(nextBlockHeight, extraNonce)
if err != nil {
return nil, err
}
coinbaseTx, err := createCoinbaseTx(coinbaseScript, nextBlockHeight,
payToAddress)
if err != nil {
return nil, err
}
numCoinbaseSigOps := int64(blockchain.CountSigOps(coinbaseTx))
// Get the current source transactions and create a priority queue to
// hold the transactions which are ready for inclusion into a block
// along with some priority related and fee metadata. Reserve the same
// number of items that are available for the priority queue. Also,
// choose the initial sort order for the priority queue based on whether
// or not there is an area allocated for high-priority transactions.
sourceTxns := txSource.MiningDescs()
sortedByFee := policy.BlockPrioritySize == 0
priorityQueue := newTxPriorityQueue(len(sourceTxns), sortedByFee)
// Create a slice to hold the transactions to be included in the
// generated block with reserved space. Also create a transaction
// store to house all of the input transactions so multiple lookups
// can be avoided.
blockTxns := make([]*btcutil.Tx, 0, len(sourceTxns))
blockTxns = append(blockTxns, coinbaseTx)
blockTxStore := make(blockchain.TxStore)
// dependers is used to track transactions which depend on another
// transaction in the source pool. This, in conjunction with the
// dependsOn map kept with each dependent transaction helps quickly
// determine which dependent transactions are now eligible for inclusion
// in the block once each transaction has been included.
dependers := make(map[wire.ShaHash]*list.List)
// Create slices to hold the fees and number of signature operations
// for each of the selected transactions and add an entry for the
// coinbase. This allows the code below to simply append details about
// a transaction as it is selected for inclusion in the final block.
// However, since the total fees aren't known yet, use a dummy value for
// the coinbase fee which will be updated later.
txFees := make([]int64, 0, len(sourceTxns))
txSigOpCounts := make([]int64, 0, len(sourceTxns))
txFees = append(txFees, -1) // Updated once known
txSigOpCounts = append(txSigOpCounts, numCoinbaseSigOps)
minrLog.Debugf("Considering %d transactions for inclusion to new block",
len(sourceTxns))
mempoolLoop:
for _, txDesc := range sourceTxns {
// A block can't have more than one coinbase or contain
// non-finalized transactions.
tx := txDesc.Tx
if blockchain.IsCoinBase(tx) {
minrLog.Tracef("Skipping coinbase tx %s", tx.Sha())
continue
}
if !blockchain.IsFinalizedTransaction(tx, nextBlockHeight,
timeSource.AdjustedTime()) {
minrLog.Tracef("Skipping non-finalized tx %s", tx.Sha())
continue
}
// Fetch all of the transactions referenced by the inputs to
// this transaction. NOTE: This intentionally does not fetch
// inputs from the mempool since a transaction which depends on
// other transactions in the mempool must come after those
// dependencies in the final generated block.
txStore, err := blockManager.FetchTransactionStore(tx)
if err != nil {
minrLog.Warnf("Unable to fetch transaction store for "+
"tx %s: %v", tx.Sha(), err)
continue
}
// Setup dependencies for any transactions which reference
// other transactions in the mempool so they can be properly
// ordered below.
prioItem := &txPrioItem{tx: tx}
for _, txIn := range tx.MsgTx().TxIn {
originHash := &txIn.PreviousOutPoint.Hash
originIndex := txIn.PreviousOutPoint.Index
txData, exists := txStore[*originHash]
if !exists || txData.Err != nil || txData.Tx == nil {
if !txSource.HaveTransaction(originHash) {
minrLog.Tracef("Skipping tx %s because "+
"it references tx %s which is "+
"not available", tx.Sha,
originHash)
continue mempoolLoop
}
// The transaction is referencing another
// transaction in the source pool, so setup an
// ordering dependency.
depList, exists := dependers[*originHash]
if !exists {
depList = list.New()
dependers[*originHash] = depList
}
depList.PushBack(prioItem)
if prioItem.dependsOn == nil {
prioItem.dependsOn = make(
map[wire.ShaHash]struct{})
}
prioItem.dependsOn[*originHash] = struct{}{}
// Skip the check below. We already know the
// referenced transaction is available.
continue
}
// Ensure the output index in the referenced transaction
// is available.
msgTx := txData.Tx.MsgTx()
if originIndex > uint32(len(msgTx.TxOut)) {
minrLog.Tracef("Skipping tx %s because "+
"it references output %d of tx %s "+
"which is out of bounds", tx.Sha,
originIndex, originHash)
continue mempoolLoop
}
}
// Calculate the final transaction priority using the input
// value age sum as well as the adjusted transaction size. The
// formula is: sum(inputValue * inputAge) / adjustedTxSize
prioItem.priority = calcPriority(tx.MsgTx(), txStore, nextBlockHeight)
// Calculate the fee in Satoshi/kB.
txSize := tx.MsgTx().SerializeSize()
prioItem.feePerKB = (txDesc.Fee * 1000) / int64(txSize)
prioItem.fee = txDesc.Fee
// Add the transaction to the priority queue to mark it ready
// for inclusion in the block unless it has dependencies.
if prioItem.dependsOn == nil {
heap.Push(priorityQueue, prioItem)
}
// Merge the store which contains all of the input transactions
// for this transaction into the input transaction store. This
// allows the code below to avoid a second lookup.
mergeTxStore(blockTxStore, txStore)
}
minrLog.Tracef("Priority queue len %d, dependers len %d",
priorityQueue.Len(), len(dependers))
// The starting block size is the size of the block header plus the max
// possible transaction count size, plus the size of the coinbase
// transaction.
blockSize := blockHeaderOverhead + uint32(coinbaseTx.MsgTx().SerializeSize())
blockSigOps := numCoinbaseSigOps
totalFees := int64(0)
// Choose which transactions make it into the block.
for priorityQueue.Len() > 0 {
// Grab the highest priority (or highest fee per kilobyte
// depending on the sort order) transaction.
prioItem := heap.Pop(priorityQueue).(*txPrioItem)
tx := prioItem.tx
// Grab the list of transactions which depend on this one (if
// any) and remove the entry for this transaction as it will
// either be included or skipped, but in either case the deps
// are no longer needed.
deps := dependers[*tx.Sha()]
delete(dependers, *tx.Sha())
// Enforce maximum block size. Also check for overflow.
txSize := uint32(tx.MsgTx().SerializeSize())
blockPlusTxSize := blockSize + txSize
if blockPlusTxSize < blockSize || blockPlusTxSize >= policy.BlockMaxSize {
minrLog.Tracef("Skipping tx %s because it would exceed "+
"the max block size", tx.Sha())
logSkippedDeps(tx, deps)
continue
}
// Enforce maximum signature operations per block. Also check
// for overflow.
numSigOps := int64(blockchain.CountSigOps(tx))
if blockSigOps+numSigOps < blockSigOps ||
blockSigOps+numSigOps > blockchain.MaxSigOpsPerBlock {
minrLog.Tracef("Skipping tx %s because it would "+
"exceed the maximum sigops per block", tx.Sha())
logSkippedDeps(tx, deps)
continue
}
numP2SHSigOps, err := blockchain.CountP2SHSigOps(tx, false,
blockTxStore)
if err != nil {
minrLog.Tracef("Skipping tx %s due to error in "+
"CountP2SHSigOps: %v", tx.Sha(), err)
logSkippedDeps(tx, deps)
continue
}
numSigOps += int64(numP2SHSigOps)
if blockSigOps+numSigOps < blockSigOps ||
blockSigOps+numSigOps > blockchain.MaxSigOpsPerBlock {
minrLog.Tracef("Skipping tx %s because it would "+
"exceed the maximum sigops per block (p2sh)",
tx.Sha())
logSkippedDeps(tx, deps)
continue
}
// Skip free transactions once the block is larger than the
// minimum block size.
if sortedByFee &&
prioItem.feePerKB < int64(policy.TxMinFreeFee) &&
blockPlusTxSize >= policy.BlockMinSize {
minrLog.Tracef("Skipping tx %s with feePerKB %.2f "+
"< TxMinFreeFee %d and block size %d >= "+
"minBlockSize %d", tx.Sha(), prioItem.feePerKB,
policy.TxMinFreeFee, blockPlusTxSize,
policy.BlockMinSize)
logSkippedDeps(tx, deps)
continue
}
// Prioritize by fee per kilobyte once the block is larger than
// the priority size or there are no more high-priority
// transactions.
if !sortedByFee && (blockPlusTxSize >= policy.BlockPrioritySize ||
prioItem.priority <= minHighPriority) {
minrLog.Tracef("Switching to sort by fees per "+
"kilobyte blockSize %d >= BlockPrioritySize "+
"%d || priority %.2f <= minHighPriority %.2f",
blockPlusTxSize, policy.BlockPrioritySize,
prioItem.priority, minHighPriority)
sortedByFee = true
priorityQueue.SetLessFunc(txPQByFee)
// Put the transaction back into the priority queue and
// skip it so it is re-priortized by fees if it won't
// fit into the high-priority section or the priority is
// too low. Otherwise this transaction will be the
// final one in the high-priority section, so just fall
// though to the code below so it is added now.
if blockPlusTxSize > policy.BlockPrioritySize ||
prioItem.priority < minHighPriority {
heap.Push(priorityQueue, prioItem)
continue
}
}
// Ensure the transaction inputs pass all of the necessary
// preconditions before allowing it to be added to the block.
_, err = blockchain.CheckTransactionInputs(tx, nextBlockHeight,
blockTxStore)
if err != nil {
minrLog.Tracef("Skipping tx %s due to error in "+
"CheckTransactionInputs: %v", tx.Sha(), err)
logSkippedDeps(tx, deps)
continue
}
err = blockchain.ValidateTransactionScripts(tx, blockTxStore,
txscript.StandardVerifyFlags, server.sigCache)
if err != nil {
minrLog.Tracef("Skipping tx %s due to error in "+
"ValidateTransactionScripts: %v", tx.Sha(), err)
logSkippedDeps(tx, deps)
continue
}
// Spend the transaction inputs in the block transaction store
// and add an entry for it to ensure any transactions which
// reference this one have it available as an input and can
// ensure they aren't double spending.
spendTransaction(blockTxStore, tx, nextBlockHeight)
// Add the transaction to the block, increment counters, and
// save the fees and signature operation counts to the block
// template.
blockTxns = append(blockTxns, tx)
blockSize += txSize
blockSigOps += numSigOps
totalFees += prioItem.fee
txFees = append(txFees, prioItem.fee)
txSigOpCounts = append(txSigOpCounts, numSigOps)
minrLog.Tracef("Adding tx %s (priority %.2f, feePerKB %.2f)",
prioItem.tx.Sha(), prioItem.priority, prioItem.feePerKB)
// Add transactions which depend on this one (and also do not
// have any other unsatisified dependencies) to the priority
// queue.
if deps != nil {
for e := deps.Front(); e != nil; e = e.Next() {
// Add the transaction to the priority queue if
// there are no more dependencies after this
// one.
item := e.Value.(*txPrioItem)
delete(item.dependsOn, *tx.Sha())
if len(item.dependsOn) == 0 {
heap.Push(priorityQueue, item)
}
}
}
}
// Now that the actual transactions have been selected, update the
// block size for the real transaction count and coinbase value with
// the total fees accordingly.
blockSize -= wire.MaxVarIntPayload -
uint32(wire.VarIntSerializeSize(uint64(len(blockTxns))))
coinbaseTx.MsgTx().TxOut[0].Value += totalFees
txFees[0] = -totalFees
// Calculate the required difficulty for the block. The timestamp
// is potentially adjusted to ensure it comes after the median time of
// the last several blocks per the chain consensus rules.
ts, err := medianAdjustedTime(chainState, timeSource)
if err != nil {
return nil, err
}
requiredDifficulty, err := blockManager.CalcNextRequiredDifficulty(ts)
if err != nil {
return nil, err
}
// Create a new block ready to be solved.
merkles := blockchain.BuildMerkleTreeStore(blockTxns)
var msgBlock wire.MsgBlock
msgBlock.Header = wire.BlockHeader{
Version: generatedBlockVersion,
PrevBlock: *prevHash,
MerkleRoot: *merkles[len(merkles)-1],
Timestamp: ts,
Bits: requiredDifficulty,
}
for _, tx := range blockTxns {
if err := msgBlock.AddTransaction(tx.MsgTx()); err != nil {
return nil, err
}
}
// Finally, perform a full check on the created block against the chain
// consensus rules to ensure it properly connects to the current best
// chain with no issues.
block := btcutil.NewBlock(&msgBlock)
block.SetHeight(nextBlockHeight)
if err := blockManager.CheckConnectBlock(block); err != nil {
return nil, err
}
minrLog.Debugf("Created new block template (%d transactions, %d in "+
"fees, %d signature operations, %d bytes, target difficulty "+
"%064x)", len(msgBlock.Transactions), totalFees, blockSigOps,
blockSize, blockchain.CompactToBig(msgBlock.Header.Bits))
return &BlockTemplate{
block: &msgBlock,
fees: txFees,
sigOpCounts: txSigOpCounts,
height: nextBlockHeight,
validPayAddress: payToAddress != nil,
}, nil
}
func TestLimitAndSkipFetchTxsForAddr(t *testing.T) {
testDb, err := setUpTestDb(t, "tstdbtxaddr")
if err != nil {
t.Errorf("Failed to open test database %v", err)
return
}
defer testDb.cleanUpFunc()
// Insert a block with some fake test transactions. The block will have
// 10 copies of a fake transaction involving same address.
addrString := "1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa"
targetAddr, err := btcutil.DecodeAddress(addrString, &chaincfg.MainNetParams)
if err != nil {
t.Fatalf("Unable to decode test address: %v", err)
}
outputScript, err := txscript.PayToAddrScript(targetAddr)
if err != nil {
t.Fatalf("Unable make test pkScript %v", err)
}
fakeTxOut := wire.NewTxOut(10, outputScript)
var emptyHash wire.ShaHash
fakeHeader := wire.NewBlockHeader(&emptyHash, &emptyHash, 1, 1)
msgBlock := wire.NewMsgBlock(fakeHeader)
for i := 0; i < 10; i++ {
mtx := wire.NewMsgTx()
mtx.AddTxOut(fakeTxOut)
msgBlock.AddTransaction(mtx)
}
// Insert the test block into the DB.
testBlock := btcutil.NewBlock(msgBlock)
newheight, err := testDb.db.InsertBlock(testBlock)
if err != nil {
t.Fatalf("Unable to insert block into db: %v", err)
}
// Create and insert an address index for out test addr.
txLoc, _ := testBlock.TxLoc()
index := make(database.BlockAddrIndex)
for i := range testBlock.Transactions() {
var hash160 [ripemd160.Size]byte
scriptAddr := targetAddr.ScriptAddress()
copy(hash160[:], scriptAddr[:])
index[hash160] = append(index[hash160], &txLoc[i])
}
blkSha := testBlock.Sha()
err = testDb.db.UpdateAddrIndexForBlock(blkSha, newheight, index)
if err != nil {
t.Fatalf("UpdateAddrIndexForBlock: failed to index"+
" addrs for block #%d (%s) "+
"err %v", newheight, blkSha, err)
return
}
// Try skipping the first 4 results, should get 6 in return.
txReply, txSkipped, err := testDb.db.FetchTxsForAddr(targetAddr, 4, 100000, false)
if err != nil {
t.Fatalf("Unable to fetch transactions for address: %v", err)
}
if txSkipped != 4 {
t.Fatalf("Did not correctly return skipped amount"+
" got %v txs, expected %v", txSkipped, 4)
}
if len(txReply) != 6 {
t.Fatalf("Did not correctly skip forward in txs for address reply"+
" got %v txs, expected %v", len(txReply), 6)
}
// Limit the number of results to 3.
txReply, txSkipped, err = testDb.db.FetchTxsForAddr(targetAddr, 0, 3, false)
if err != nil {
t.Fatalf("Unable to fetch transactions for address: %v", err)
}
if txSkipped != 0 {
t.Fatalf("Did not correctly return skipped amount"+
" got %v txs, expected %v", txSkipped, 0)
}
if len(txReply) != 3 {
t.Fatalf("Did not correctly limit in txs for address reply"+
" got %v txs, expected %v", len(txReply), 3)
}
// Skip 1, limit 5.
txReply, txSkipped, err = testDb.db.FetchTxsForAddr(targetAddr, 1, 5, false)
if err != nil {
t.Fatalf("Unable to fetch transactions for address: %v", err)
}
if txSkipped != 1 {
t.Fatalf("Did not correctly return skipped amount"+
" got %v txs, expected %v", txSkipped, 1)
}
if len(txReply) != 5 {
t.Fatalf("Did not correctly limit in txs for address reply"+
" got %v txs, expected %v", len(txReply), 5)
}
}
// TestHaveBlock tests the HaveBlock API to ensure proper functionality.
func TestHaveBlock(t *testing.T) {
// Load up blocks such that there is a side chain.
// (genesis block) -> 1 -> 2 -> 3 -> 4
// \-> 3a
testFiles := []string{
"blk_0_to_4.dat.bz2",
"blk_3A.dat.bz2",
}
var blocks []*btcutil.Block
for _, file := range testFiles {
blockTmp, err := loadBlocks(file)
if err != nil {
t.Errorf("Error loading file: %v\n", err)
return
}
for _, block := range blockTmp {
blocks = append(blocks, block)
}
}
// Create a new database and chain instance to run tests against.
chain, teardownFunc, err := chainSetup("haveblock")
if err != nil {
t.Errorf("Failed to setup chain instance: %v", err)
return
}
defer teardownFunc()
// Since we're not dealing with the real block chain, disable
// checkpoints and set the coinbase maturity to 1.
chain.DisableCheckpoints(true)
blockchain.TstSetCoinbaseMaturity(1)
timeSource := blockchain.NewMedianTime()
for i := 1; i < len(blocks); i++ {
isOrphan, err := chain.ProcessBlock(blocks[i], timeSource,
blockchain.BFNone)
if err != nil {
t.Errorf("ProcessBlock fail on block %v: %v\n", i, err)
return
}
if isOrphan {
t.Errorf("ProcessBlock incorrectly returned block %v "+
"is an orphan\n", i)
return
}
}
// Insert an orphan block.
isOrphan, err := chain.ProcessBlock(btcutil.NewBlock(&Block100000),
timeSource, blockchain.BFNone)
if err != nil {
t.Errorf("Unable to process block: %v", err)
return
}
if !isOrphan {
t.Errorf("ProcessBlock indicated block is an not orphan when " +
"it should be\n")
return
}
tests := []struct {
hash string
want bool
}{
// Genesis block should be present (in the main chain).
{hash: chaincfg.MainNetParams.GenesisHash.String(), want: true},
// Block 3a should be present (on a side chain).
{hash: "00000000474284d20067a4d33f6a02284e6ef70764a3a26d6a5b9df52ef663dd", want: true},
// Block 100000 should be present (as an orphan).
{hash: "000000000003ba27aa200b1cecaad478d2b00432346c3f1f3986da1afd33e506", want: true},
// Random hashes should not be availble.
{hash: "123", want: false},
}
for i, test := range tests {
hash, err := wire.NewShaHashFromStr(test.hash)
if err != nil {
t.Errorf("NewShaHashFromStr: %v", err)
continue
}
result, err := chain.HaveBlock(hash)
if err != nil {
t.Errorf("HaveBlock #%d unexpected error: %v", i, err)
return
}
if result != test.want {
t.Errorf("HaveBlock #%d got %v want %v", i, result,
test.want)
continue
}
}
}
// GenerateNBlocks generates the requested number of blocks. It is self
// contained in that it creates block templates and attempts to solve them while
// detecting when it is performing stale work and reacting accordingly by
// generating a new block template. When a block is solved, it is submitted.
// The function returns a list of the hashes of generated blocks.
func (m *CPUMiner) GenerateNBlocks(n uint32) ([]*wire.ShaHash, error) {
m.Lock()
// Respond with an error if there's virtually 0 chance of CPU-mining a block.
if !m.server.chainParams.GenerateSupported {
m.Unlock()
return nil, errors.New("No support for `generate` on the current " +
"network, " + m.server.chainParams.Net.String() +
", as it's unlikely to be possible to CPU-mine a block.")
}
// Respond with an error if server is already mining.
if m.started || m.discreteMining {
m.Unlock()
return nil, errors.New("Server is already CPU mining. Please call " +
"`setgenerate 0` before calling discrete `generate` commands.")
}
m.started = true
m.discreteMining = true
m.speedMonitorQuit = make(chan struct{})
m.wg.Add(1)
go m.speedMonitor()
m.Unlock()
minrLog.Tracef("Generating %d blocks", n)
i := uint32(0)
blockHashes := make([]*wire.ShaHash, n, n)
// Start a ticker which is used to signal checks for stale work and
// updates to the speed monitor.
ticker := time.NewTicker(time.Second * hashUpdateSecs)
defer ticker.Stop()
for {
// Read updateNumWorkers in case someone tries a `setgenerate` while
// we're generating. We can ignore it as the `generate` RPC call only
// uses 1 worker.
select {
case <-m.updateNumWorkers:
default:
}
// Grab the lock used for block submission, since the current block will
// be changing and this would otherwise end up building a new block
// template on a block that is in the process of becoming stale.
m.submitBlockLock.Lock()
_, curHeight := m.server.blockManager.chainState.Best()
// Choose a payment address at random.
rand.Seed(time.Now().UnixNano())
payToAddr := cfg.miningAddrs[rand.Intn(len(cfg.miningAddrs))]
// Create a new block template using the available transactions
// in the memory pool as a source of transactions to potentially
// include in the block.
template, err := NewBlockTemplate(m.policy, m.server, payToAddr)
m.submitBlockLock.Unlock()
if err != nil {
errStr := fmt.Sprintf("Failed to create new block "+
"template: %v", err)
minrLog.Errorf(errStr)
continue
}
// Attempt to solve the block. The function will exit early
// with false when conditions that trigger a stale block, so
// a new block template can be generated. When the return is
// true a solution was found, so submit the solved block.
if m.solveBlock(template.block, curHeight+1, ticker, nil) {
block := btcutil.NewBlock(template.block)
m.submitBlock(block)
blockHashes[i] = block.Sha()
i++
if i == n {
minrLog.Tracef("Generated %d blocks", i)
m.Lock()
close(m.speedMonitorQuit)
m.wg.Wait()
m.started = false
m.discreteMining = false
m.Unlock()
return blockHashes, nil
}
}
}
}
// generateBlocks is a worker that is controlled by the miningWorkerController.
// It is self contained in that it creates block templates and attempts to solve
// them while detecting when it is performing stale work and reacting
// accordingly by generating a new block template. When a block is solved, it
// is submitted.
//
// It must be run as a goroutine.
func (m *CPUMiner) generateBlocks(quit chan struct{}) {
minrLog.Tracef("Starting generate blocks worker")
// Start a ticker which is used to signal checks for stale work and
// updates to the speed monitor.
ticker := time.NewTicker(time.Second * hashUpdateSecs)
defer ticker.Stop()
out:
for {
// Quit when the miner is stopped.
select {
case <-quit:
break out
default:
// Non-blocking select to fall through
}
// Wait until there is a connection to at least one other peer
// since there is no way to relay a found block or receive
// transactions to work on when there are no connected peers.
if m.server.ConnectedCount() == 0 {
time.Sleep(time.Second)
continue
}
// No point in searching for a solution before the chain is
// synced. Also, grab the same lock as used for block
// submission, since the current block will be changing and
// this would otherwise end up building a new block template on
// a block that is in the process of becoming stale.
m.submitBlockLock.Lock()
_, curHeight := m.server.blockManager.chainState.Best()
if curHeight != 0 && !m.server.blockManager.IsCurrent() {
m.submitBlockLock.Unlock()
time.Sleep(time.Second)
continue
}
// Choose a payment address at random.
rand.Seed(time.Now().UnixNano())
payToAddr := cfg.miningAddrs[rand.Intn(len(cfg.miningAddrs))]
// Create a new block template using the available transactions
// in the memory pool as a source of transactions to potentially
// include in the block.
template, err := NewBlockTemplate(m.policy, m.server, payToAddr)
m.submitBlockLock.Unlock()
if err != nil {
errStr := fmt.Sprintf("Failed to create new block "+
"template: %v", err)
minrLog.Errorf(errStr)
continue
}
// Attempt to solve the block. The function will exit early
// with false when conditions that trigger a stale block, so
// a new block template can be generated. When the return is
// true a solution was found, so submit the solved block.
if m.solveBlock(template.block, curHeight+1, ticker, quit) {
block := btcutil.NewBlock(template.block)
m.submitBlock(block)
}
}
m.workerWg.Done()
minrLog.Tracef("Generate blocks worker done")
}
// TestPersistence ensures that values stored are still valid after closing and
// reopening the database.
func TestPersistence(t *testing.T) {
t.Parallel()
// Create a new database to run tests against.
dbPath := filepath.Join(os.TempDir(), "ffldb-persistencetest")
_ = os.RemoveAll(dbPath)
db, err := database.Create(dbType, dbPath, blockDataNet)
if err != nil {
t.Errorf("Failed to create test database (%s) %v", dbType, err)
return
}
defer os.RemoveAll(dbPath)
defer db.Close()
// Create a bucket, put some values into it, and store a block so they
// can be tested for existence on re-open.
bucket1Key := []byte("bucket1")
storeValues := map[string]string{
"b1key1": "foo1",
"b1key2": "foo2",
"b1key3": "foo3",
}
genesisBlock := btcutil.NewBlock(chaincfg.MainNetParams.GenesisBlock)
genesisHash := chaincfg.MainNetParams.GenesisHash
err = db.Update(func(tx database.Tx) error {
metadataBucket := tx.Metadata()
if metadataBucket == nil {
return fmt.Errorf("Metadata: unexpected nil bucket")
}
bucket1, err := metadataBucket.CreateBucket(bucket1Key)
if err != nil {
return fmt.Errorf("CreateBucket: unexpected error: %v",
err)
}
for k, v := range storeValues {
err := bucket1.Put([]byte(k), []byte(v))
if err != nil {
return fmt.Errorf("Put: unexpected error: %v",
err)
}
}
if err := tx.StoreBlock(genesisBlock); err != nil {
return fmt.Errorf("StoreBlock: unexpected error: %v",
err)
}
return nil
})
if err != nil {
t.Errorf("Update: unexpected error: %v", err)
return
}
// Close and reopen the database to ensure the values persist.
db.Close()
db, err = database.Open(dbType, dbPath, blockDataNet)
if err != nil {
t.Errorf("Failed to open test database (%s) %v", dbType, err)
return
}
defer db.Close()
// Ensure the values previously stored in the 3rd namespace still exist
// and are correct.
err = db.View(func(tx database.Tx) error {
metadataBucket := tx.Metadata()
if metadataBucket == nil {
return fmt.Errorf("Metadata: unexpected nil bucket")
}
bucket1 := metadataBucket.Bucket(bucket1Key)
if bucket1 == nil {
return fmt.Errorf("Bucket1: unexpected nil bucket")
}
for k, v := range storeValues {
gotVal := bucket1.Get([]byte(k))
if !reflect.DeepEqual(gotVal, []byte(v)) {
return fmt.Errorf("Get: key '%s' does not "+
"match expected value - got %s, want %s",
k, gotVal, v)
}
}
genesisBlockBytes, _ := genesisBlock.Bytes()
gotBytes, err := tx.FetchBlock(genesisHash)
if err != nil {
return fmt.Errorf("FetchBlock: unexpected error: %v",
err)
}
if !reflect.DeepEqual(gotBytes, genesisBlockBytes) {
return fmt.Errorf("FetchBlock: stored block mismatch")
}
return nil
})
if err != nil {
t.Errorf("View: unexpected error: %v", err)
return
}
}
func Test_dupTx(t *testing.T) {
// Ignore db remove errors since it means we didn't have an old one.
dbname := fmt.Sprintf("tstdbdup0")
dbnamever := dbname + ".ver"
_ = os.RemoveAll(dbname)
_ = os.RemoveAll(dbnamever)
db, err := database.CreateDB("leveldb", dbname)
if err != nil {
t.Errorf("Failed to open test database %v", err)
return
}
defer os.RemoveAll(dbname)
defer os.RemoveAll(dbnamever)
defer func() {
if err := db.Close(); err != nil {
t.Errorf("Close: unexpected error: %v", err)
}
}()
testdatafile := filepath.Join("testdata", "blocks1-256.bz2")
blocks, err := loadBlocks(t, testdatafile)
if err != nil {
t.Errorf("Unable to load blocks from test data for: %v",
err)
return
}
var lastSha *wire.ShaHash
// Populate with the fisrt 256 blocks, so we have blocks to 'mess with'
err = nil
out:
for height := int32(0); height < int32(len(blocks)); height++ {
block := blocks[height]
// except for NoVerify which does not allow lookups check inputs
mblock := block.MsgBlock()
var txneededList []*wire.ShaHash
for _, tx := range mblock.Transactions {
for _, txin := range tx.TxIn {
if txin.PreviousOutPoint.Index == uint32(4294967295) {
continue
}
origintxsha := &txin.PreviousOutPoint.Hash
txneededList = append(txneededList, origintxsha)
exists, err := db.ExistsTxSha(origintxsha)
if err != nil {
t.Errorf("ExistsTxSha: unexpected error %v ", err)
}
if !exists {
t.Errorf("referenced tx not found %v ", origintxsha)
}
_, err = db.FetchTxBySha(origintxsha)
if err != nil {
t.Errorf("referenced tx not found %v err %v ", origintxsha, err)
}
}
}
txlist := db.FetchUnSpentTxByShaList(txneededList)
for _, txe := range txlist {
if txe.Err != nil {
t.Errorf("tx list fetch failed %v err %v ", txe.Sha, txe.Err)
break out
}
}
newheight, err := db.InsertBlock(block)
if err != nil {
t.Errorf("failed to insert block %v err %v", height, err)
break out
}
if newheight != height {
t.Errorf("height mismatch expect %v returned %v", height, newheight)
break out
}
newSha, blkid, err := db.NewestSha()
if err != nil {
t.Errorf("failed to obtain latest sha %v %v", height, err)
}
if blkid != height {
t.Errorf("height doe not match latest block height %v %v %v", blkid, height, err)
}
blkSha := block.Sha()
if *newSha != *blkSha {
t.Errorf("Newest block sha does not match freshly inserted one %v %v %v ", newSha, blkSha, err)
}
lastSha = blkSha
}
// generate a new block based on the last sha
// these block are not verified, so there are a bunch of garbage fields
// in the 'generated' block.
var bh wire.BlockHeader
bh.Version = 2
bh.PrevBlock = *lastSha
// Bits, Nonce are not filled in
mblk := wire.NewMsgBlock(&bh)
hash, _ := wire.NewShaHashFromStr("df2b060fa2e5e9c8ed5eaf6a45c13753ec8c63282b2688322eba40cd98ea067a")
po := wire.NewOutPoint(hash, 0)
txI := wire.NewTxIn(po, []byte("garbage"))
txO := wire.NewTxOut(50000000, []byte("garbageout"))
var tx wire.MsgTx
tx.AddTxIn(txI)
tx.AddTxOut(txO)
mblk.AddTransaction(&tx)
blk := btcutil.NewBlock(mblk)
fetchList := []*wire.ShaHash{hash}
listReply := db.FetchUnSpentTxByShaList(fetchList)
for _, lr := range listReply {
if lr.Err != nil {
t.Errorf("sha %v spent %v err %v\n", lr.Sha,
lr.TxSpent, lr.Err)
}
}
_, err = db.InsertBlock(blk)
if err != nil {
t.Errorf("failed to insert phony block %v", err)
}
// ok, did it 'spend' the tx ?
listReply = db.FetchUnSpentTxByShaList(fetchList)
for _, lr := range listReply {
if lr.Err != database.ErrTxShaMissing {
t.Errorf("sha %v spent %v err %v\n", lr.Sha,
lr.TxSpent, lr.Err)
}
}
txlist := blk.Transactions()
for _, tx := range txlist {
txsha := tx.Sha()
txReply, err := db.FetchTxBySha(txsha)
if err != nil {
t.Errorf("fully spent lookup %v err %v\n", hash, err)
} else {
for _, lr := range txReply {
if lr.Err != nil {
t.Errorf("stx %v spent %v err %v\n", lr.Sha,
lr.TxSpent, lr.Err)
}
}
}
}
t.Logf("Dropping block")
err = db.DropAfterBlockBySha(lastSha)
if err != nil {
t.Errorf("failed to drop spending block %v", err)
}
}
// loadBlocks loads the blocks contained in the testdata directory and returns
// a slice of them.
func loadBlocks(t *testing.T, dataFile string, network wire.BitcoinNet) ([]*btcutil.Block, error) {
// Open the file that contains the blocks for reading.
fi, err := os.Open(dataFile)
if err != nil {
t.Errorf("failed to open file %v, err %v", dataFile, err)
return nil, err
}
defer func() {
if err := fi.Close(); err != nil {
t.Errorf("failed to close file %v %v", dataFile,
err)
}
}()
dr := bzip2.NewReader(fi)
// Set the first block as the genesis block.
blocks := make([]*btcutil.Block, 0, 256)
genesis := btcutil.NewBlock(chaincfg.MainNetParams.GenesisBlock)
blocks = append(blocks, genesis)
// Load the remaining blocks.
for height := 1; ; height++ {
var net uint32
err := binary.Read(dr, binary.LittleEndian, &net)
if err == io.EOF {
// Hit end of file at the expected offset. No error.
break
}
if err != nil {
t.Errorf("Failed to load network type for block %d: %v",
height, err)
return nil, err
}
if net != uint32(network) {
t.Errorf("Block doesn't match network: %v expects %v",
net, network)
return nil, err
}
var blockLen uint32
err = binary.Read(dr, binary.LittleEndian, &blockLen)
if err != nil {
t.Errorf("Failed to load block size for block %d: %v",
height, err)
return nil, err
}
// Read the block.
blockBytes := make([]byte, blockLen)
_, err = io.ReadFull(dr, blockBytes)
if err != nil {
t.Errorf("Failed to load block %d: %v", height, err)
return nil, err
}
// Deserialize and store the block.
block, err := btcutil.NewBlockFromBytes(blockBytes)
if err != nil {
t.Errorf("Failed to parse block %v: %v", height, err)
return nil, err
}
blocks = append(blocks, block)
}
return blocks, nil
}
// chainSetup is used to create a new db and chain instance with the genesis
// block already inserted. In addition to the new chain instnce, it returns
// a teardown function the caller should invoke when done testing to clean up.
func chainSetup(dbName string) (*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.CreateDB(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.CreateDB(testDbType, dbPath)
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() {
dbVersionPath := filepath.Join(testDbRoot, dbName+".ver")
db.Sync()
db.Close()
os.RemoveAll(dbPath)
os.Remove(dbVersionPath)
os.RemoveAll(testDbRoot)
}
}
// Insert the main network genesis block. This is part of the initial
// database setup.
genesisBlock := btcutil.NewBlock(chaincfg.MainNetParams.GenesisBlock)
_, err := db.InsertBlock(genesisBlock)
if err != nil {
teardown()
err := fmt.Errorf("failed to insert genesis block: %v", err)
return nil, nil, err
}
chain := blockchain.New(db, &chaincfg.MainNetParams, nil, nil)
return chain, teardown, nil
}
// This example demonstrates creating a new database, using a managed read-write
// transaction to store a block, and using a managed read-only transaction to
// fetch the block.
func Example_blockStorageAndRetrieval() {
// This example assumes the ffldb driver is imported.
//
// import (
// "github.com/chrjen/btcd/database"
// _ "github.com/chrjen/btcd/database/ffldb"
// )
// Create a database and schedule it to be closed and removed on exit.
// Typically you wouldn't want to remove the database right away like
// this, nor put it in the temp directory, but it's done here to ensure
// the example cleans up after itself.
dbPath := filepath.Join(os.TempDir(), "exampleblkstorage")
db, err := database.Create("ffldb", dbPath, wire.MainNet)
if err != nil {
fmt.Println(err)
return
}
defer os.RemoveAll(dbPath)
defer db.Close()
// Use the Update function of the database to perform a managed
// read-write transaction and store a genesis block in the database as
// and example.
err = db.Update(func(tx database.Tx) error {
genesisBlock := chaincfg.MainNetParams.GenesisBlock
return tx.StoreBlock(btcutil.NewBlock(genesisBlock))
})
if err != nil {
fmt.Println(err)
return
}
// Use the View function of the database to perform a managed read-only
// transaction and fetch the block stored above.
var loadedBlockBytes []byte
err = db.Update(func(tx database.Tx) error {
genesisHash := chaincfg.MainNetParams.GenesisHash
blockBytes, err := tx.FetchBlock(genesisHash)
if err != nil {
return err
}
// As documented, all data fetched from the database is only
// valid during a database transaction in order to support
// zero-copy backends. Thus, make a copy of the data so it
// can be used outside of the transaction.
loadedBlockBytes = make([]byte, len(blockBytes))
copy(loadedBlockBytes, blockBytes)
return nil
})
if err != nil {
fmt.Println(err)
return
}
// Typically at this point, the block could be deserialized via the
// wire.MsgBlock.Deserialize function or used in its serialized form
// depending on need. However, for this example, just display the
// number of serialized bytes to show it was loaded as expected.
fmt.Printf("Serialized block size: %d bytes\n", len(loadedBlockBytes))
// Output:
// Serialized block size: 285 bytes
}
// loadBlocks loads the blocks contained in the testdata directory and returns
// a slice of them.
func loadBlocks(t *testing.T) ([]*btcutil.Block, error) {
if len(savedBlocks) != 0 {
return savedBlocks, nil
}
var dr io.Reader
fi, err := os.Open(blockDataFile)
if err != nil {
t.Errorf("failed to open file %v, err %v", blockDataFile, err)
return nil, err
}
if strings.HasSuffix(blockDataFile, ".bz2") {
z := bzip2.NewReader(fi)
dr = z
} else {
dr = fi
}
defer func() {
if err := fi.Close(); err != nil {
t.Errorf("failed to close file %v %v", blockDataFile, err)
}
}()
// Set the first block as the genesis block.
blocks := make([]*btcutil.Block, 0, 256)
genesis := btcutil.NewBlock(chaincfg.MainNetParams.GenesisBlock)
blocks = append(blocks, genesis)
for height := int64(1); err == nil; height++ {
var rintbuf uint32
err := binary.Read(dr, binary.LittleEndian, &rintbuf)
if err == io.EOF {
// hit end of file at expected offset: no warning
height--
err = nil
break
}
if err != nil {
t.Errorf("failed to load network type, err %v", err)
break
}
if rintbuf != uint32(network) {
t.Errorf("Block doesn't match network: %v expects %v",
rintbuf, network)
break
}
err = binary.Read(dr, binary.LittleEndian, &rintbuf)
blocklen := rintbuf
rbytes := make([]byte, blocklen)
// read block
dr.Read(rbytes)
block, err := btcutil.NewBlockFromBytes(rbytes)
if err != nil {
t.Errorf("failed to parse block %v", height)
return nil, err
}
blocks = append(blocks, block)
}
savedBlocks = blocks
return blocks, nil
}
// TestClosed ensure calling the interface functions on a closed database
// returns appropriate errors for the interface functions that return errors
// and does not panic or otherwise misbehave for functions which do not return
// errors.
func TestClosed(t *testing.T) {
db, err := database.CreateDB("memdb")
if err != nil {
t.Errorf("Failed to open test database %v", err)
return
}
_, err = db.InsertBlock(btcutil.NewBlock(chaincfg.MainNetParams.GenesisBlock))
if err != nil {
t.Errorf("InsertBlock: %v", err)
}
if err := db.Close(); err != nil {
t.Errorf("Close: unexpected error %v", err)
}
genesisHash := chaincfg.MainNetParams.GenesisHash
if err := db.DropAfterBlockBySha(genesisHash); err != memdb.ErrDbClosed {
t.Errorf("DropAfterBlockBySha: unexpected error %v", err)
}
if _, err := db.ExistsSha(genesisHash); err != memdb.ErrDbClosed {
t.Errorf("ExistsSha: Unexpected error: %v", err)
}
if _, err := db.FetchBlockBySha(genesisHash); err != memdb.ErrDbClosed {
t.Errorf("FetchBlockBySha: unexpected error %v", err)
}
if _, err := db.FetchBlockShaByHeight(0); err != memdb.ErrDbClosed {
t.Errorf("FetchBlockShaByHeight: unexpected error %v", err)
}
if _, err := db.FetchHeightRange(0, 1); err != memdb.ErrDbClosed {
t.Errorf("FetchHeightRange: unexpected error %v", err)
}
genesisCoinbaseTx := chaincfg.MainNetParams.GenesisBlock.Transactions[0]
coinbaseHash := genesisCoinbaseTx.TxSha()
if _, err := db.ExistsTxSha(&coinbaseHash); err != memdb.ErrDbClosed {
t.Errorf("ExistsTxSha: unexpected error %v", err)
}
if _, err := db.FetchTxBySha(genesisHash); err != memdb.ErrDbClosed {
t.Errorf("FetchTxBySha: unexpected error %v", err)
}
requestHashes := []*wire.ShaHash{genesisHash}
reply := db.FetchTxByShaList(requestHashes)
if len(reply) != len(requestHashes) {
t.Errorf("FetchUnSpentTxByShaList unexpected number of replies "+
"got: %d, want: %d", len(reply), len(requestHashes))
}
for i, txLR := range reply {
wantReply := &database.TxListReply{
Sha: requestHashes[i],
Err: memdb.ErrDbClosed,
}
if !reflect.DeepEqual(wantReply, txLR) {
t.Errorf("FetchTxByShaList unexpected reply\ngot: %v\n"+
"want: %v", txLR, wantReply)
}
}
reply = db.FetchUnSpentTxByShaList(requestHashes)
if len(reply) != len(requestHashes) {
t.Errorf("FetchUnSpentTxByShaList unexpected number of replies "+
"got: %d, want: %d", len(reply), len(requestHashes))
}
for i, txLR := range reply {
wantReply := &database.TxListReply{
Sha: requestHashes[i],
Err: memdb.ErrDbClosed,
}
if !reflect.DeepEqual(wantReply, txLR) {
t.Errorf("FetchUnSpentTxByShaList unexpected reply\n"+
"got: %v\nwant: %v", txLR, wantReply)
}
}
if _, _, err := db.NewestSha(); err != memdb.ErrDbClosed {
t.Errorf("NewestSha: unexpected error %v", err)
}
if err := db.Sync(); err != memdb.ErrDbClosed {
t.Errorf("Sync: unexpected error %v", err)
}
if err := db.RollbackClose(); err != memdb.ErrDbClosed {
t.Errorf("RollbackClose: unexpected error %v", err)
}
if err := db.Close(); err != memdb.ErrDbClosed {
t.Errorf("Close: unexpected error %v", err)
}
}