core, event/filter, xeth: refactored filter system
Moved the filtering system from `event` to `eth/filters` package and removed the `core.Filter` object. The `filters.Filter` object now requires a `common.Database` rather than a `eth.Backend` and invokes the `core.GetBlockByX` directly rather than thru a "manager".
This commit is contained in:
Jeffrey Wilcke
211
eth/filters/filter.go
Normal file
211
eth/filters/filter.go
Normal file
@@ -0,0 +1,211 @@
|
||||
// Copyright 2014 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 filters
|
||||
|
||||
import (
|
||||
"math"
|
||||
|
||||
"github.com/ethereum/go-ethereum/common"
|
||||
"github.com/ethereum/go-ethereum/core"
|
||||
"github.com/ethereum/go-ethereum/core/state"
|
||||
"github.com/ethereum/go-ethereum/core/types"
|
||||
)
|
||||
|
||||
type AccountChange struct {
|
||||
Address, StateAddress []byte
|
||||
}
|
||||
|
||||
// Filtering interface
|
||||
type Filter struct {
|
||||
db common.Database
|
||||
earliest int64
|
||||
latest int64
|
||||
skip int
|
||||
address []common.Address
|
||||
max int
|
||||
topics [][]common.Hash
|
||||
|
||||
BlockCallback func(*types.Block, state.Logs)
|
||||
TransactionCallback func(*types.Transaction)
|
||||
LogsCallback func(state.Logs)
|
||||
}
|
||||
|
||||
// Create a new filter which uses a bloom filter on blocks to figure out whether a particular block
|
||||
// is interesting or not.
|
||||
func New(db common.Database) *Filter {
|
||||
return &Filter{db: db}
|
||||
}
|
||||
|
||||
// Set the earliest and latest block for filtering.
|
||||
// -1 = latest block (i.e., the current block)
|
||||
// hash = particular hash from-to
|
||||
func (self *Filter) SetEarliestBlock(earliest int64) {
|
||||
self.earliest = earliest
|
||||
}
|
||||
|
||||
func (self *Filter) SetLatestBlock(latest int64) {
|
||||
self.latest = latest
|
||||
}
|
||||
|
||||
func (self *Filter) SetAddress(addr []common.Address) {
|
||||
self.address = addr
|
||||
}
|
||||
|
||||
func (self *Filter) SetTopics(topics [][]common.Hash) {
|
||||
self.topics = topics
|
||||
}
|
||||
|
||||
func (self *Filter) SetMax(max int) {
|
||||
self.max = max
|
||||
}
|
||||
|
||||
func (self *Filter) SetSkip(skip int) {
|
||||
self.skip = skip
|
||||
}
|
||||
|
||||
// Run filters logs with the current parameters set
|
||||
func (self *Filter) Find() state.Logs {
|
||||
earliestBlock := core.GetCurrentBlock(self.db)
|
||||
var earliestBlockNo uint64 = uint64(self.earliest)
|
||||
if self.earliest == -1 {
|
||||
earliestBlockNo = earliestBlock.NumberU64()
|
||||
}
|
||||
var latestBlockNo uint64 = uint64(self.latest)
|
||||
if self.latest == -1 {
|
||||
latestBlockNo = earliestBlock.NumberU64()
|
||||
}
|
||||
|
||||
var (
|
||||
logs state.Logs
|
||||
block = core.GetBlockByNumber(self.db, latestBlockNo)
|
||||
)
|
||||
|
||||
done:
|
||||
for i := 0; block != nil; i++ {
|
||||
// Quit on latest
|
||||
switch {
|
||||
case block.NumberU64() == 0:
|
||||
break done
|
||||
case block.NumberU64() < earliestBlockNo:
|
||||
break done
|
||||
case self.max <= len(logs):
|
||||
break done
|
||||
}
|
||||
|
||||
// Use bloom filtering to see if this block is interesting given the
|
||||
// current parameters
|
||||
if self.bloomFilter(block) {
|
||||
// Get the logs of the block
|
||||
var (
|
||||
receipts = core.GetBlockReceipts(self.db, block.Hash())
|
||||
unfiltered state.Logs
|
||||
)
|
||||
for _, receipt := range receipts {
|
||||
unfiltered = append(unfiltered, receipt.Logs()...)
|
||||
}
|
||||
logs = append(logs, self.FilterLogs(unfiltered)...)
|
||||
}
|
||||
|
||||
block = core.GetBlockByHash(self.db, block.ParentHash())
|
||||
}
|
||||
|
||||
skip := int(math.Min(float64(len(logs)), float64(self.skip)))
|
||||
|
||||
return logs[skip:]
|
||||
}
|
||||
|
||||
func includes(addresses []common.Address, a common.Address) bool {
|
||||
for _, addr := range addresses {
|
||||
if addr == a {
|
||||
return true
|
||||
}
|
||||
}
|
||||
|
||||
return false
|
||||
}
|
||||
|
||||
func (self *Filter) FilterLogs(logs state.Logs) state.Logs {
|
||||
var ret state.Logs
|
||||
|
||||
// Filter the logs for interesting stuff
|
||||
Logs:
|
||||
for _, log := range logs {
|
||||
if len(self.address) > 0 && !includes(self.address, log.Address) {
|
||||
continue
|
||||
}
|
||||
|
||||
logTopics := make([]common.Hash, len(self.topics))
|
||||
copy(logTopics, log.Topics)
|
||||
|
||||
// If the to filtered topics is greater than the amount of topics in
|
||||
// logs, skip.
|
||||
if len(self.topics) > len(log.Topics) {
|
||||
continue Logs
|
||||
}
|
||||
|
||||
for i, topics := range self.topics {
|
||||
var match bool
|
||||
for _, topic := range topics {
|
||||
// common.Hash{} is a match all (wildcard)
|
||||
if (topic == common.Hash{}) || log.Topics[i] == topic {
|
||||
match = true
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
if !match {
|
||||
continue Logs
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
ret = append(ret, log)
|
||||
}
|
||||
|
||||
return ret
|
||||
}
|
||||
|
||||
func (self *Filter) bloomFilter(block *types.Block) bool {
|
||||
if len(self.address) > 0 {
|
||||
var included bool
|
||||
for _, addr := range self.address {
|
||||
if types.BloomLookup(block.Bloom(), addr) {
|
||||
included = true
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
if !included {
|
||||
return false
|
||||
}
|
||||
}
|
||||
|
||||
for _, sub := range self.topics {
|
||||
var included bool
|
||||
for _, topic := range sub {
|
||||
if (topic == common.Hash{}) || types.BloomLookup(block.Bloom(), topic) {
|
||||
included = true
|
||||
break
|
||||
}
|
||||
}
|
||||
if !included {
|
||||
return false
|
||||
}
|
||||
}
|
||||
|
||||
return true
|
||||
}
|
||||
133
eth/filters/filter_system.go
Normal file
133
eth/filters/filter_system.go
Normal file
@@ -0,0 +1,133 @@
|
||||
// Copyright 2014 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 filters implements an ethereum filtering system for block,
|
||||
// transactions and log events.
|
||||
package filters
|
||||
|
||||
import (
|
||||
"sync"
|
||||
|
||||
"github.com/ethereum/go-ethereum/core"
|
||||
"github.com/ethereum/go-ethereum/core/state"
|
||||
"github.com/ethereum/go-ethereum/event"
|
||||
)
|
||||
|
||||
// FilterSystem manages filters that filter specific events such as
|
||||
// block, transaction and log events. The Filtering system can be used to listen
|
||||
// for specific LOG events fires by the EVM (Ethereum Virtual Machine).
|
||||
type FilterSystem struct {
|
||||
eventMux *event.TypeMux
|
||||
|
||||
filterMu sync.RWMutex
|
||||
filterId int
|
||||
filters map[int]*Filter
|
||||
|
||||
quit chan struct{}
|
||||
}
|
||||
|
||||
// NewFilterSystem returns a newly allocated filter manager
|
||||
func NewFilterSystem(mux *event.TypeMux) *FilterSystem {
|
||||
fs := &FilterSystem{
|
||||
eventMux: mux,
|
||||
filters: make(map[int]*Filter),
|
||||
}
|
||||
go fs.filterLoop()
|
||||
return fs
|
||||
}
|
||||
|
||||
// Stop quits the filter loop required for polling events
|
||||
func (fs *FilterSystem) Stop() {
|
||||
close(fs.quit)
|
||||
}
|
||||
|
||||
// Add adds a filter to the filter manager
|
||||
func (fs *FilterSystem) Add(filter *Filter) (id int) {
|
||||
fs.filterMu.Lock()
|
||||
defer fs.filterMu.Unlock()
|
||||
id = fs.filterId
|
||||
fs.filters[id] = filter
|
||||
fs.filterId++
|
||||
|
||||
return id
|
||||
}
|
||||
|
||||
// Remove removes a filter by filter id
|
||||
func (fs *FilterSystem) Remove(id int) {
|
||||
fs.filterMu.Lock()
|
||||
defer fs.filterMu.Unlock()
|
||||
if _, ok := fs.filters[id]; ok {
|
||||
delete(fs.filters, id)
|
||||
}
|
||||
}
|
||||
|
||||
// Get retrieves a filter installed using Add The filter may not be modified.
|
||||
func (fs *FilterSystem) Get(id int) *Filter {
|
||||
fs.filterMu.RLock()
|
||||
defer fs.filterMu.RUnlock()
|
||||
return fs.filters[id]
|
||||
}
|
||||
|
||||
// filterLoop waits for specific events from ethereum and fires their handlers
|
||||
// when the filter matches the requirements.
|
||||
func (fs *FilterSystem) filterLoop() {
|
||||
// Subscribe to events
|
||||
events := fs.eventMux.Subscribe(
|
||||
//core.PendingBlockEvent{},
|
||||
core.ChainEvent{},
|
||||
core.TxPreEvent{},
|
||||
state.Logs(nil))
|
||||
|
||||
out:
|
||||
for {
|
||||
select {
|
||||
case <-fs.quit:
|
||||
break out
|
||||
case event := <-events.Chan():
|
||||
switch event := event.(type) {
|
||||
case core.ChainEvent:
|
||||
fs.filterMu.RLock()
|
||||
for _, filter := range fs.filters {
|
||||
if filter.BlockCallback != nil {
|
||||
filter.BlockCallback(event.Block, event.Logs)
|
||||
}
|
||||
}
|
||||
fs.filterMu.RUnlock()
|
||||
|
||||
case core.TxPreEvent:
|
||||
fs.filterMu.RLock()
|
||||
for _, filter := range fs.filters {
|
||||
if filter.TransactionCallback != nil {
|
||||
filter.TransactionCallback(event.Tx)
|
||||
}
|
||||
}
|
||||
fs.filterMu.RUnlock()
|
||||
|
||||
case state.Logs:
|
||||
fs.filterMu.RLock()
|
||||
for _, filter := range fs.filters {
|
||||
if filter.LogsCallback != nil {
|
||||
msgs := filter.FilterLogs(event)
|
||||
if len(msgs) > 0 {
|
||||
filter.LogsCallback(msgs)
|
||||
}
|
||||
}
|
||||
}
|
||||
fs.filterMu.RUnlock()
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user