Go

This page describes how to build and send Solana transactions using Go

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Solana's transaction sending service is no longer bound to the subscription plan. API key could be required from Authentication. If you need to increase the TPS limit, please contactarrow-up-right us and we will handle it as soon as possible.

HTTP

package main

import (
	"bytes"
	"context"
	"encoding/json"
	"fmt"
	"io"
	"math/rand"
	"net/http"
	"time"

	"github.com/gagliardetto/solana-go"
	"github.com/gagliardetto/solana-go/programs/system"
	"github.com/gagliardetto/solana-go/rpc"
)

const (
	httpEndpoint     = "http://frankfurt.solana.blockrazor.xyz:443/sendTransaction"
	healthEndpoint   = "http://frankfurt.solana.blockrazor.xyz:443/health"
	mainNetRPC       = ""
	authKey          = ""
	privateKey       = ""
	publicKey        = ""
	amount           = 200_000
	tipAmount        = 1_000_000
	mode             = "fast"
	safeWindow       = 5
	revertProtection = false
)

var tipAccounts = []string{
	"Gywj98ophM7GmkDdaWs4isqZnDdFCW7B46TXmKfvyqSm",
	"FjmZZrFvhnqqb9ThCuMVnENaM3JGVuGWNyCAxRJcFpg9",
	"6No2i3aawzHsjtThw81iq1EXPJN6rh8eSJCLaYZfKDTG",
	"A9cWowVAiHe9pJfKAj3TJiN9VpbzMUq6E4kEvf5mUT22",
	"68Pwb4jS7eZATjDfhmTXgRJjCiZmw1L7Huy4HNpnxJ3o",
	"4ABhJh5rZPjv63RBJBuyWzBK3g9gWMUQdTZP2kiW31V9",
	"B2M4NG5eyZp5SBQrSdtemzk5TqVuaWGQnowGaCBt8GyM",
	"5jA59cXMKQqZAVdtopv8q3yyw9SYfiE3vUCbt7p8MfVf",
	"5YktoWygr1Bp9wiS1xtMtUki1PeYuuzuCF98tqwYxf61",
	"295Avbam4qGShBYK7E9H5Ldew4B3WyJGmgmXfiWdeeyV",
	"EDi4rSy2LZgKJX74mbLTFk4mxoTgT6F7HxxzG2HBAFyK",
	"BnGKHAC386n4Qmv9xtpBVbRaUTKixjBe3oagkPFKtoy6",
	"Dd7K2Fp7AtoN8xCghKDRmyqr5U169t48Tw5fEd3wT9mq",
	"AP6qExwrbRgBAVaehg4b5xHENX815sMabtBzUzVB4v8S",
}

var httpClient = &http.Client{
	Timeout: 10 * time.Second,
}

type SendRequest struct {
	Transaction      string `json:"transaction"`
	Mode             string `json:"mode"`
	SafeWindow       int    `json:"safeWindow"`
	RevertProtection bool   `json:"revertProtection"`
}

type SendResponse struct {
	Signature string `json:"signature"`
}
type HealthResponse struct {
	Result string `json:"result"`
}

func main() {
	// Pre-warm: perform an initial health check to establish the HTTP connection
	err := pingHealth()
	if err != nil {
		fmt.Printf("health check failed: %v\n", err)
	}
	// Start a background goroutine to periodically send /health requests
	// For low-frequency users, this keeps the HTTP connection alive (warm)
	go func() {
		for {
			err := pingHealth()
			if err != nil {
				fmt.Printf("health check failed: %v\n", err)
			}
			time.Sleep(30 * time.Second)
		}
	}()
	// send transactions
	if err := sendTx(); err != nil {
		fmt.Printf("send tx failed: %v\n", err)
	}
}

func pingHealth() error {
	req, err := http.NewRequest("GET", healthEndpoint, nil)
	if err != nil {
		return err
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("apikey", authKey)
	resp, err := httpClient.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	// ⚠️ Important Note:
	// According to the Go net/http documentation, in order for the underlying TCP connection
	// to be reused (i.e. kept alive), the response body must be fully read and closed.
	// Otherwise, the Transport may not reuse the connection for future requests.
	// Reference: https://pkg.go.dev/net/http#Response
	// > "The default HTTP client's Transport may not reuse HTTP/1.x 'keep-alive' TCP connections
	//    if the Body is not read to completion and closed."

	// Read the full response body to enable connection reuse
	bodyBytes, _ := io.ReadAll(resp.Body)
	var healthRes HealthResponse
	if err := json.Unmarshal(bodyBytes, &healthRes); err != nil {
		return fmt.Errorf("decode error: %v", err)
	}

	return nil
}

func sendTx() error {
	account, err := solana.WalletFromPrivateKeyBase58(privateKey)
	if err != nil {
		return err
	}
	receivePub := solana.MustPublicKeyFromBase58(publicKey)
	tipPub := solana.MustPublicKeyFromBase58(tipAccounts[rand.Intn(len(tipAccounts))])

	rpcClient := rpc.New(mainNetRPC)
	blockhash, err := rpcClient.GetLatestBlockhash(context.TODO(), rpc.CommitmentFinalized)
	if err != nil {
		return fmt.Errorf("[get blockhash] %v", err)
	}

	transferIx := system.NewTransferInstruction(amount, account.PublicKey(), receivePub).Build()
	tipIx := system.NewTransferInstruction(tipAmount, account.PublicKey(), tipPub).Build()

	tx, err := solana.NewTransaction(
		[]solana.Instruction{tipIx, transferIx},
		blockhash.Value.Blockhash,
		solana.TransactionPayer(account.PublicKey()),
	)
	if err != nil {
		return fmt.Errorf("build tx error: %v", err)
	}

	_, err = tx.Sign(func(key solana.PublicKey) *solana.PrivateKey {
		if account.PublicKey().Equals(key) {
			return &account.PrivateKey
		}
		return nil
	})
	if err != nil {
		return fmt.Errorf("sign tx error: %v", err)
	}

	txBase64, err := tx.ToBase64()
	if err != nil {
		return err
	}

	reqBody := SendRequest{
		Transaction:      txBase64,
		Mode:             mode,
		SafeWindow:       safeWindow,
		RevertProtection: revertProtection,
	}
	jsonBody, _ := json.Marshal(reqBody)

	httpReq, err := http.NewRequest("POST", httpEndpoint, bytes.NewBuffer(jsonBody))
	if err != nil {
		return err
	}
	httpReq.Header.Set("Content-Type", "application/json")
	httpReq.Header.Set("apikey", authKey)
	resp, err := httpClient.Do(httpReq)
	if err != nil {
		return fmt.Errorf("send http error: %v", err)
	}
	defer resp.Body.Close()

	bodyBytes, _ := io.ReadAll(resp.Body)
	var sendRes SendResponse
	if err := json.Unmarshal(bodyBytes, &sendRes); err != nil {
		return fmt.Errorf("decode error: %v", err)
	}
	fmt.Printf("[send tx] response: %+v\n", sendRes)
	return nil
}

Response Example

Success

Error

gRPC

Proto

Response Example

Success

Error

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