// AbsorbTx absorbs money into wallet from a tx
func (t *TxStore) AbsorbTx(tx *wire.MsgTx) error {
if tx == nil {
return fmt.Errorf("Tried to add nil tx")
}
var hits uint32
var acq int64
// check if any of the tx's outputs match my adrs
for i, out := range tx.TxOut { // in each output of tx
for _, a := range t.Adrs { // compare to each adr we have
// more correct would be to check for full script
// contains could have false positive? (p2sh/p2pkh same hash ..?)
if bytes.Contains(out.PkScript, a.ScriptAddress()) { // hit
hits++
acq += out.Value
var newu Utxo
newu.KeyIdx = a.KeyIdx
newu.Txo = *out
var newop wire.OutPoint
newop.Hash = tx.TxSha()
newop.Index = uint32(i)
newu.Op = newop
t.Utxos = append(t.Utxos, newu)
break
}
}
}
log.Printf("%d hits, acquired %d", hits, acq)
t.Sum += acq
return nil
}
// Ingest puts a tx into the DB atomically. This can result in a
// gain, a loss, or no result. Gain or loss in satoshis is returned.
func (ts *TxStore) Ingest(tx *wire.MsgTx, height int32) (uint32, error) {
var hits uint32
var err error
var spentOPs [][]byte
var nUtxoBytes [][]byte
// tx has been OK'd by SPV; check tx sanity
utilTx := btcutil.NewTx(tx) // convert for validation
// checks basic stuff like there are inputs and ouputs
err = blockchain.CheckTransactionSanity(utilTx)
if err != nil {
return hits, err
}
// note that you can't check signatures; this is SPV.
// 0 conf SPV means pretty much nothing. Anyone can say anything.
// before entering into db, serialize all inputs of the ingested tx
for _, txin := range tx.TxIn {
nOP, err := outPointToBytes(&txin.PreviousOutPoint)
if err != nil {
return hits, err
}
spentOPs = append(spentOPs, nOP)
}
// also generate PKscripts for all addresses (maybe keep storing these?)
for _, adr := range ts.Adrs {
// iterate through all our addresses
aPKscript, err := txscript.PayToAddrScript(adr.PkhAdr)
if err != nil {
return hits, err
}
// iterate through all outputs of this tx
for i, out := range tx.TxOut {
if bytes.Equal(out.PkScript, aPKscript) { // new utxo for us
var newu Utxo
newu.AtHeight = height
newu.KeyIdx = adr.KeyIdx
newu.Value = out.Value
var newop wire.OutPoint
newop.Hash = tx.TxSha()
newop.Index = uint32(i)
newu.Op = newop
b, err := newu.ToBytes()
if err != nil {
return hits, err
}
nUtxoBytes = append(nUtxoBytes, b)
hits++
break // only one match
}
}
}
err = ts.StateDB.Update(func(btx *bolt.Tx) error {
// get all 4 buckets
duf := btx.Bucket(BKTUtxos)
// sta := btx.Bucket(BKTState)
old := btx.Bucket(BKTStxos)
txns := btx.Bucket(BKTTxns)
if duf == nil || old == nil || txns == nil {
return fmt.Errorf("error: db not initialized")
}
// first see if we lose utxos
// iterate through duffel bag and look for matches
// this makes us lose money, which is regrettable, but we need to know.
for _, nOP := range spentOPs {
duf.ForEach(func(k, v []byte) error {
if bytes.Equal(k, nOP) { // matched, we lost utxo
// do all this just to figure out value we lost
x := make([]byte, len(k)+len(v))
copy(x, k)
copy(x[len(k):], v)
lostTxo, err := UtxoFromBytes(x)
if err != nil {
return err
}
hits++
// then delete the utxo from duf, save to old
err = duf.Delete(k)
if err != nil {
return err
}
// after deletion, save stxo to old bucket
var st Stxo // generate spent txo
st.Utxo = lostTxo // assign outpoint
st.SpendHeight = height // spent at height
st.SpendTxid = tx.TxSha() // spent by txid
stxb, err := st.ToBytes() // serialize
if err != nil {
return err
}
err = old.Put(k, stxb) // write k:v outpoint:stxo bytes
if err != nil {
return err
}
// store this relevant tx
sha := tx.TxSha()
var buf bytes.Buffer
tx.Serialize(&buf)
err = txns.Put(sha.Bytes(), buf.Bytes())
if err != nil {
return err
}
return nil // matched utxo k, won't match another
}
return nil // no match
})
} // done losing utxos, next gain utxos
// next add all new utxos to db, this is quick as the work is above
for _, ub := range nUtxoBytes {
err = duf.Put(ub[:36], ub[36:])
if err != nil {
return err
}
}
return nil
})
return hits, err
}