Writing to Contracts

To calling writing method of the contract, you need to provide the account private key for authentication.

package main
import (
	store "...The path of the store.go file..."
	"context"
	"crypto/ecdsa"
	"fmt"
	"log"
	"math/big"
	"github.com/PhoenixGlobal/Phoenix-Chain-SDK/ethereum/accounts/abi/bind"
	"github.com/PhoenixGlobal/Phoenix-Chain-SDK/ethereum/ethclient"
	"github.com/PhoenixGlobal/Phoenix-Chain-SDK/libs/common"
	"github.com/PhoenixGlobal/Phoenix-Chain-SDK/libs/crypto"
)
func main() {
	client, err := ethclient.Dial("https://dataseed1.phoenix.global/rpc")
	if err != nil {
		log.Fatal(err)
	}
	privateKey, err := crypto.HexToECDSA("your private key")
	if err != nil {
		log.Fatal(err)
	}
	publicKey := privateKey.Public()
	publicKeyECDSA, ok := publicKey.(*ecdsa.PublicKey)
	if !ok {
		log.Fatal("cannot assert type: publicKey is not of type *ecdsa.PublicKey")
	}
	fromAddress := crypto.PubkeyToAddress(*publicKeyECDSA)
	nonce, err := client.PendingNonceAt(context.Background(), fromAddress)
	if err != nil {
		log.Fatal(err)
	}
	gasPrice, err := client.SuggestGasPrice(context.Background())
	if err != nil {
		log.Fatal(err)
	}
	auth := bind.NewKeyedTransactor(privateKey)
	auth.Nonce = big.NewInt(int64(nonce))
	auth.Value = big.NewInt(0)
	auth.GasLimit = uint64(300000)
	auth.GasPrice = gasPrice
	contractAddress := common.HexToAddress("0x9aC8B849A8b6Fc14F8dEcfa6A22dB41671B38eFB")
	instance, err := store.NewStore(contractAddress, client)
	if err != nil {
		log.Fatal(err)
	}
	key := [32]byte{}
	value := [32]byte{}
	copy(key[:], []byte("storeKey"))
	copy(value[:], []byte("storeValue"))
	// calling the writing method
	tx, err := instance.SetItem(auth, key, value)
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println("transaction hash:", tx.Hash().Hex())
	result, err := instance.Items(nil, key)
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(string(result[:])) // "storeValue"
}