quorum/ethchain/filter.go

147 lines
3.2 KiB
Go

package ethchain
import (
"bytes"
"fmt"
"github.com/ethereum/eth-go/ethstate"
"github.com/ethereum/eth-go/ethutil"
)
// Filtering interface
type Filter struct {
eth EthManager
earliest []byte
latest []byte
skip int
from, to []byte
max int
}
// Create a new filter which uses a bloom filter on blocks to figure out whether a particular block
// is interesting or not.
func NewFilter(eth EthManager) *Filter {
return &Filter{eth: eth}
}
// 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 interface{}) {
e := ethutil.NewValue(earliest)
// Check for -1 (latest) otherwise assume bytes
if e.Int() == -1 {
self.earliest = self.eth.BlockChain().CurrentBlock.Hash()
} else if e.Len() > 0 {
self.earliest = e.Bytes()
} else {
panic(fmt.Sprintf("earliest has to be either -1 or a valid hash: %v (%T)", e, e.Val))
}
}
func (self *Filter) SetLatestBlock(latest interface{}) {
l := ethutil.NewValue(latest)
// Check for -1 (latest) otherwise assume bytes
if l.Int() == -1 {
self.latest = self.eth.BlockChain().CurrentBlock.Hash()
} else if l.Len() > 0 {
self.latest = l.Bytes()
} else {
panic(fmt.Sprintf("latest has to be either -1 or a valid hash: %v", l))
}
}
func (self *Filter) SetFrom(addr []byte) {
self.from = addr
}
func (self *Filter) SetTo(addr []byte) {
self.to = addr
}
func (self *Filter) SetMax(max int) {
self.max = max
}
func (self *Filter) SetSkip(skip int) {
self.skip = skip
}
// Run filters messages with the current parameters set
func (self *Filter) Find() []*ethstate.Message {
var messages []*ethstate.Message
block := self.eth.BlockChain().GetBlock(self.latest)
// skip N blocks (useful for pagination)
if self.skip > 0 {
for i := 0; i < i; i++ {
block = self.eth.BlockChain().GetBlock(block.PrevHash)
}
}
// Start block filtering
quit := false
for i := 1; !quit && block != nil; i++ {
// Mark last check
if self.max == i || (len(self.earliest) > 0 && bytes.Compare(block.Hash(), self.earliest) == 0) {
quit = true
}
// Use bloom filtering to see if this block is interesting given the
// current parameters
if self.bloomFilter(block) {
// Get the messages of the block
msgs, err := self.eth.StateManager().GetMessages(block)
if err != nil {
chainlogger.Warnln("err: filter get messages ", err)
break
}
// Filter the messages for interesting stuff
for _, message := range msgs {
if len(self.to) > 0 && bytes.Compare(message.To, self.to) != 0 {
continue
}
if len(self.from) > 0 && bytes.Compare(message.From, self.from) != 0 {
continue
}
messages = append(messages, message)
}
}
block = self.eth.BlockChain().GetBlock(block.PrevHash)
}
return messages
}
func (self *Filter) bloomFilter(block *Block) bool {
fk := append([]byte("bloom"), block.Hash()...)
bin, err := self.eth.Db().Get(fk)
if err != nil {
panic(err)
}
bloom := NewBloomFilter(bin)
if len(self.from) > 0 {
if !bloom.Search(self.from) {
return false
}
}
if len(self.to) > 0 {
if !bloom.Search(self.to) {
return false
}
}
return true
}