func GetTx(txid *btc.Uint256, vout int) bool { r, er := http.Get("http://blockexplorer.com/rawtx/" + txid.String()) if er == nil && r.StatusCode == 200 { defer r.Body.Close() c, _ := ioutil.ReadAll(r.Body) var txx onetx er = json.Unmarshal(c[:], &txx) if er == nil { tx := new(btc.Tx) tx.Version = txx.Ver tx.TxIn = make([]*btc.TxIn, len(txx.In)) for i := range txx.In { tx.TxIn[i] = new(btc.TxIn) tx.TxIn[i].Input.Hash = btc.NewUint256FromString(txx.In[i].Prev_out.Hash).Hash tx.TxIn[i].Input.Vout = txx.In[i].Prev_out.N tx.TxIn[i].ScriptSig, _ = btc.DecodeScript(txx.In[i].ScriptSig) tx.TxIn[i].Sequence = 0xffffffff } tx.TxOut = make([]*btc.TxOut, len(txx.Out)) for i := range txx.Out { tx.TxOut[i] = new(btc.TxOut) tx.TxOut[i].Value = btc.ParseValue(txx.Out[i].Value) tx.TxOut[i].Pk_script, _ = btc.DecodeScript(txx.Out[i].ScriptPubKey) } tx.Lock_time = txx.Lock_time rawtx := tx.Serialize() curid := btc.NewSha2Hash(rawtx) if !curid.Equal(txid) { fmt.Println("The downloaded transaction does not match its ID.") return false } ioutil.WriteFile("balance/"+curid.String()+".tx", rawtx, 0666) return true } else { fmt.Println("json.Unmarshal:", er.Error()) } } else { if er != nil { fmt.Println("http.Get:", er.Error()) } else { fmt.Println("StatusCode=", r.StatusCode) } } return false }
// Download (and re-assemble) raw transaction from blockexplorer.com func GetTxFromExplorer(txid *btc.Uint256) ([]byte, []byte) { url := "http://blockexplorer.com/rawtx/" + txid.String() r, er := http.Get(url) if er == nil && r.StatusCode == 200 { defer r.Body.Close() c, _ := ioutil.ReadAll(r.Body) var txx onetx er = json.Unmarshal(c[:], &txx) if er == nil { // This part looks weird, but this is how I solved seq=FFFFFFFF, if the field not present: for i := range txx.In { txx.In[i].Sequence = 0xffffffff } json.Unmarshal(c[:], &txx) // ... end of the weird solution tx := new(btc.Tx) tx.Version = txx.Ver tx.TxIn = make([]*btc.TxIn, len(txx.In)) for i := range txx.In { tx.TxIn[i] = new(btc.TxIn) tx.TxIn[i].Input.Hash = btc.NewUint256FromString(txx.In[i].Prev_out.Hash).Hash tx.TxIn[i].Input.Vout = txx.In[i].Prev_out.N if txx.In[i].Prev_out.N == 0xffffffff && txx.In[i].Prev_out.Hash == "0000000000000000000000000000000000000000000000000000000000000000" { tx.TxIn[i].ScriptSig, _ = hex.DecodeString(txx.In[i].Coinbase) } else { tx.TxIn[i].ScriptSig, _ = btc.DecodeScript(txx.In[i].ScriptSig) } tx.TxIn[i].Sequence = txx.In[i].Sequence } tx.TxOut = make([]*btc.TxOut, len(txx.Out)) for i := range txx.Out { am, er := btc.StringToSatoshis(txx.Out[i].Value) if er != nil { fmt.Println("Incorrect BTC amount", txx.Out[i].Value, er.Error()) return nil, nil } tx.TxOut[i] = new(btc.TxOut) tx.TxOut[i].Value = am tx.TxOut[i].Pk_script, _ = btc.DecodeScript(txx.Out[i].ScriptPubKey) } tx.Lock_time = txx.Lock_time rawtx := tx.Serialize() if txx.Size != uint(len(rawtx)) { fmt.Printf("Transaction size mismatch: %d expexted, %d decoded\n", txx.Size, len(rawtx)) return nil, rawtx } curid := btc.NewSha2Hash(rawtx) if !curid.Equal(txid) { fmt.Println("The downloaded transaction does not match its ID.", txid.String()) return nil, rawtx } return rawtx, rawtx } else { fmt.Println("json.Unmarshal:", er.Error()) } } else { if er != nil { fmt.Println("http.Get:", er.Error()) } else { fmt.Println("StatusCode=", r.StatusCode) } } return nil, nil }