client, err := ethclient.Dial("infura url")
if err != nil {
log.Fatal(err)
}
log.Println(client)
privateKey, err := crypto.HexToECDSA("private key")
if err != nil {
log.Fatal(err)
}
log.Println("privatekey", privateKey)
//
publicKey := privateKey.Public()
publicKeyECDSA, ok := publicKey.(*ecdsa.PublicKey)
if !ok {
log.Fatal("error casting public key to ECDSA")
}
log.Println("publicKeyECDSA ", publicKeyECDSA)
fromAddress := crypto.PubkeyToAddress(*publicKeyECDSA)
nonce, err := client.PendingNonceAt(context.Background(), fromAddress)
if err != nil {
log.Fatal(err)
}
log.Println("fromaddress ", fromAddress)
log.Println("nonce", nonce)
//
value := big.NewInt(0) // in wei (0 eth)
gasPrice, err := client.SuggestGasPrice(context.Background())
if err != nil {
log.Fatal(err)
}
//
toAddress := common.HexToAddress("to address")
tokenAddress := common.HexToAddress("contract address")
//
transferFnSignature := []byte("transfer(address,uint256)")
hash := sha3.NewKeccak256()
hash.Write(transferFnSignature)
methodID := hash.Sum(nil)[:4]
fmt.Printf("Method ID: %s\n", hexutil.Encode(methodID))
//
paddedAddress := common.LeftPadBytes(toAddress.Bytes(), 32)
fmt.Printf("To address: %s\n", hexutil.Encode(paddedAddress))
//
amount := new(big.Int)
amount.SetString("10000000", 10) // 1000 tokens
paddedAmount := common.LeftPadBytes(amount.Bytes(), 32)
fmt.Printf("Token amount: %s", hexutil.Encode(paddedAmount))
//
var data []byte
data = append(data, methodID...)
data = append(data, paddedAddress...)
data = append(data, paddedAmount...)
//
gasLimit, err := client.EstimateGas(context.Background(), ethereum.CallMsg{
To: &toAddress,
Data: data,
})
if err != nil {
log.Fatal(err)
}
fmt.Printf("Gas limit: %d", gasLimit)
tx := types.NewTransaction(nonce, tokenAddress, value, gasLimit*2, gasPrice, data)
signedTx, err := types.SignTx(tx, types.HomesteadSigner{}, privateKey)
if err != nil {
log.Fatal(err)
}
err = client.SendTransaction(context.Background(), signedTx)
if err != nil {
log.Fatal(err)
}
fmt.Printf("Tokens sent at TX: %s", signedTx.Hash().Hex())
}
- 使用infura作为以太坊节点
- gaslimit太小容易out of gas
- etherscan上查看transaction
