go-ethereum/eth/downloader/testchain_test.go

231 lines
7.7 KiB
Go

// 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 downloader
import (
"fmt"
"math/big"
"sync"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/consensus/ethash"
"github.com/ethereum/go-ethereum/core"
"github.com/ethereum/go-ethereum/core/rawdb"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/core/vm"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/params"
)
// Test chain parameters.
var (
testKey, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
testAddress = crypto.PubkeyToAddress(testKey.PublicKey)
testDB = rawdb.NewMemoryDatabase()
testGspec = &core.Genesis{
Config: params.TestChainConfig,
Alloc: core.GenesisAlloc{testAddress: {Balance: big.NewInt(1000000000000000)}},
BaseFee: big.NewInt(params.InitialBaseFee),
}
testGenesis = testGspec.MustCommit(testDB)
)
// The common prefix of all test chains:
var testChainBase *testChain
// Different forks on top of the base chain:
var testChainForkLightA, testChainForkLightB, testChainForkHeavy *testChain
var pregenerated bool
func init() {
// Reduce some of the parameters to make the tester faster
fullMaxForkAncestry = 10000
lightMaxForkAncestry = 10000
blockCacheMaxItems = 1024
fsHeaderSafetyNet = 256
fsHeaderContCheck = 500 * time.Millisecond
testChainBase = newTestChain(blockCacheMaxItems+200, testGenesis)
var forkLen = int(fullMaxForkAncestry + 50)
var wg sync.WaitGroup
// Generate the test chains to seed the peers with
wg.Add(3)
go func() { testChainForkLightA = testChainBase.makeFork(forkLen, false, 1); wg.Done() }()
go func() { testChainForkLightB = testChainBase.makeFork(forkLen, false, 2); wg.Done() }()
go func() { testChainForkHeavy = testChainBase.makeFork(forkLen, true, 3); wg.Done() }()
wg.Wait()
// Generate the test peers used by the tests to avoid overloading during testing.
// These seemingly random chains are used in various downloader tests. We're just
// pre-generating them here.
chains := []*testChain{
testChainBase,
testChainForkLightA,
testChainForkLightB,
testChainForkHeavy,
testChainBase.shorten(1),
testChainBase.shorten(blockCacheMaxItems - 15),
testChainBase.shorten((blockCacheMaxItems - 15) / 2),
testChainBase.shorten(blockCacheMaxItems - 15 - 5),
testChainBase.shorten(MaxHeaderFetch),
testChainBase.shorten(800),
testChainBase.shorten(800 / 2),
testChainBase.shorten(800 / 3),
testChainBase.shorten(800 / 4),
testChainBase.shorten(800 / 5),
testChainBase.shorten(800 / 6),
testChainBase.shorten(800 / 7),
testChainBase.shorten(800 / 8),
testChainBase.shorten(3*fsHeaderSafetyNet + 256 + fsMinFullBlocks),
testChainBase.shorten(fsMinFullBlocks + 256 - 1),
testChainForkLightA.shorten(len(testChainBase.blocks) + 80),
testChainForkLightB.shorten(len(testChainBase.blocks) + 81),
testChainForkLightA.shorten(len(testChainBase.blocks) + MaxHeaderFetch),
testChainForkLightB.shorten(len(testChainBase.blocks) + MaxHeaderFetch),
testChainForkHeavy.shorten(len(testChainBase.blocks) + 79),
}
wg.Add(len(chains))
for _, chain := range chains {
go func(blocks []*types.Block) {
newTestBlockchain(blocks)
wg.Done()
}(chain.blocks[1:])
}
wg.Wait()
// Mark the chains pregenerated. Generating a new one will lead to a panic.
pregenerated = true
}
type testChain struct {
blocks []*types.Block
}
// newTestChain creates a blockchain of the given length.
func newTestChain(length int, genesis *types.Block) *testChain {
tc := &testChain{
blocks: []*types.Block{genesis},
}
tc.generate(length-1, 0, genesis, false)
return tc
}
// makeFork creates a fork on top of the test chain.
func (tc *testChain) makeFork(length int, heavy bool, seed byte) *testChain {
fork := tc.copy(len(tc.blocks) + length)
fork.generate(length, seed, tc.blocks[len(tc.blocks)-1], heavy)
return fork
}
// shorten creates a copy of the chain with the given length. It panics if the
// length is longer than the number of available blocks.
func (tc *testChain) shorten(length int) *testChain {
if length > len(tc.blocks) {
panic(fmt.Errorf("can't shorten test chain to %d blocks, it's only %d blocks long", length, len(tc.blocks)))
}
return tc.copy(length)
}
func (tc *testChain) copy(newlen int) *testChain {
if newlen > len(tc.blocks) {
newlen = len(tc.blocks)
}
cpy := &testChain{
blocks: append([]*types.Block{}, tc.blocks[:newlen]...),
}
return cpy
}
// generate creates a chain of n blocks starting at and including parent.
// the returned hash chain is ordered head->parent. In addition, every 22th block
// contains a transaction and every 5th an uncle to allow testing correct block
// reassembly.
func (tc *testChain) generate(n int, seed byte, parent *types.Block, heavy bool) {
blocks, _ := core.GenerateChain(testGspec.Config, parent, ethash.NewFaker(), testDB, n, func(i int, block *core.BlockGen) {
block.SetCoinbase(common.Address{seed})
// If a heavy chain is requested, delay blocks to raise difficulty
if heavy {
block.OffsetTime(-9)
}
// Include transactions to the miner to make blocks more interesting.
if parent == tc.blocks[0] && i%22 == 0 {
signer := types.MakeSigner(params.TestChainConfig, block.Number(), block.Timestamp())
tx, err := types.SignTx(types.NewTransaction(block.TxNonce(testAddress), common.Address{seed}, big.NewInt(1000), params.TxGas, block.BaseFee(), nil), signer, testKey)
if err != nil {
panic(err)
}
block.AddTx(tx)
}
// if the block number is a multiple of 5, add a bonus uncle to the block
if i > 0 && i%5 == 0 {
block.AddUncle(&types.Header{
ParentHash: block.PrevBlock(i - 2).Hash(),
Number: big.NewInt(block.Number().Int64() - 1),
})
}
})
tc.blocks = append(tc.blocks, blocks...)
}
var (
testBlockchains = make(map[common.Hash]*testBlockchain)
testBlockchainsLock sync.Mutex
)
type testBlockchain struct {
chain *core.BlockChain
gen sync.Once
}
// newTestBlockchain creates a blockchain database built by running the given blocks,
// either actually running them, or reusing a previously created one. The returned
// chains are *shared*, so *do not* mutate them.
func newTestBlockchain(blocks []*types.Block) *core.BlockChain {
// Retrieve an existing database, or create a new one
head := testGenesis.Hash()
if len(blocks) > 0 {
head = blocks[len(blocks)-1].Hash()
}
testBlockchainsLock.Lock()
if _, ok := testBlockchains[head]; !ok {
testBlockchains[head] = new(testBlockchain)
}
tbc := testBlockchains[head]
testBlockchainsLock.Unlock()
// Ensure that the database is generated
tbc.gen.Do(func() {
if pregenerated {
panic("Requested chain generation outside of init")
}
chain, err := core.NewBlockChain(rawdb.NewMemoryDatabase(), nil, testGspec, nil, ethash.NewFaker(), vm.Config{}, nil, nil)
if err != nil {
panic(err)
}
if n, err := chain.InsertChain(blocks); err != nil {
panic(fmt.Sprintf("block %d: %v", n, err))
}
tbc.chain = chain
})
return tbc.chain
}