# Fast-Tx ### Introduction {% hint style="info" %} This method does not provide MEV protection. Transactions sent through this method will be broadcast to the public mempool. {% endhint %} Fast-Tx is used to broadcast a single rawtx or a batch of transactions on the BSC high-performance network. Broadcasting a single rawtx uses the method name `SendTx`, which supports HTTP and gRPC protocols. Broadcasting a batch of rawtxes uses the method name `SendTxs`, which also supports the gRPC protocol. ### Endpoint
RegionAvailability Zone(AWS)Relay Address
Frankfurteuc1-az235.157.64.49:50051
Tokyoapne1-az454.249.93.63:50051
Irelandeuw1-az13.248.65.151:50051
Virginiause1-az452.205.173.134:50051
### Rate Limit | User Type | Limit | Price | | -------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------------ | | New registered users |

SendTx

| Free | | Paid users |

SendTx

SendTxs

| $500 / month | ### SendTx #### Request Parameter
ParametersMandatoryFormatExampleDescription
TransactionMandatoryString"0xf8……8219"signed raw tx
#### Request Example {% tabs %} {% tab title="gRPC" %} ```go package main import ( "context" "encoding/hex" "fmt" "math/big" // directory of the generated code using the provided relay.proto file pb "github.com/BlockRazorinc/relay_example/protobuf" "github.com/ethereum/go-ethereum/common" "github.com/ethereum/go-ethereum/core/types" "github.com/ethereum/go-ethereum/crypto" "github.com/ethereum/go-ethereum/rlp" "google.golang.org/grpc" ) // auth will be used to verify the credential type Authentication struct { apiKey string } func (a *Authentication) GetRequestMetadata(context.Context, ...string) (map[string]string, error) { return map[string]string{"apiKey": a.apiKey}, nil } func (a *Authentication) RequireTransportSecurity() bool { return false } func main() { // BlockRazor relay endpoint address blzrelayEndPoint := "ip:port" // auth will be used to verify the credential auth := Authentication{ "your auth token", } // open gRPC connection to BlockRazor relay var err error conn, err := grpc.Dial(blzrelayEndPoint, grpc.WithInsecure(), grpc.WithPerRPCCredentials(&auth), grpc.WithWriteBufferSize(0), grpc.WithInitialConnWindowSize(128*1024)) if err != nil { fmt.Println("error: ", err) return } // use the Gateway client connection interface. client := pb.NewGatewayClient(conn) // create context ctx := context.Background() // replace with your address from_private_address := "42b565……44d05c" to_public_address := "0x4321……3f1c66" // replace with your transaction data nonce := uint64(1) toAddress := common.HexToAddress(to_public_address) var data []byte gasPrice := big.NewInt(1e9) gasLimit := uint64(22000) value := big.NewInt(0) chainid := types.NewEIP155Signer(big.NewInt(56)) // create new transaction tx := types.NewTransaction(nonce, toAddress, value, gasLimit, gasPrice, data) privateKey, err := crypto.HexToECDSA(from_private_address) if err != nil { fmt.Println("fail to casting private key to ECDSA") return } // sign transaction by private key signedTx, err := types.SignTx(tx, chainid, privateKey) if err != nil { fmt.Println("fail to sign transaction") return } // use rlp to encode your transaction body, _ := rlp.EncodeToBytes([]types.Transaction{*signedTx}) // encode []byte to string encode_tx := hex.EncodeToString(body) // send raw tx by BlockRazor res, err := client.SendTx(ctx, &pb.SendTxRequest{Transaction: encode_tx}) if err != nil { fmt.Println("failed to send raw tx: ", err) return } else { fmt.Println("raw tx sent by BlockRazor, tx hash is ", res.TxHash) } } ``` {% endtab %} {% tab title="HTTP" %} ```bash curl \ -X POST \ -H "Content-Type: application/json" \ -d '{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":["0x02f8……869514"],"id":1}' ``` {% endtab %} {% endtabs %} #### Response Example **Success** ```json { "tx_hash":"0x2944……b2188f" } ``` **Error** ``` rpc error: code = Unknown desc = invalid transaction format ``` ### SendTxs #### Request Parameter
ParametersMandatoryFormatExampleDescription
TransactionsMandatoryArray[String]["0xf8……8219", "0xcb……2ac0"]signed raw txs
#### Request Example ```go package main import ( "context" "encoding/hex" "fmt" "math/big" // directory of the generated code using the provided relay.proto file pb "github.com/BlockRazorinc/relay_example/protobuf" "github.com/ethereum/go-ethereum/common" "github.com/ethereum/go-ethereum/core/types" "github.com/ethereum/go-ethereum/crypto" "github.com/ethereum/go-ethereum/rlp" "google.golang.org/grpc" ) // auth will be used to verify the credential type Authentication struct { apiKey string } func (a *Authentication) GetRequestMetadata(context.Context, ...string) (map[string]string, error) { return map[string]string{"apiKey": a.apiKey}, nil } func (a *Authentication) RequireTransportSecurity() bool { return false } func main() { // BlockRazor relay endpoint address blzrelayEndPoint := "ip:port" // auth will be used to verify the credential auth := Authentication{ "your auth token", } // open gRPC connection to BlockRazor relay var err error conn, err := grpc.Dial(blzrelayEndPoint, grpc.WithInsecure(), grpc.WithPerRPCCredentials(&auth), grpc.WithWriteBufferSize(0), grpc.WithInitialConnWindowSize(128*1024)) if err != nil { fmt.Println("error: ", err) return } // use the Gateway client connection interface client := pb.NewGatewayClient(conn) // create context ctx := context.Background() // replace with your address from_private_address1 := "6c0456……8b8003" from_private_address2 := "42b565……44d05c" to_public_address := "0x4321……3f1c66" // replace with your transaction data nonce1 := uint64(1) nonce2 := uint64(1) toAddress := common.HexToAddress(to_public_address) var data []byte gasPrice := big.NewInt(1e9) gasLimit := uint64(22000) value := big.NewInt(0) chainid := types.NewEIP155Signer(big.NewInt(56)) // create new transaction tx1 := types.NewTransaction(nonce1, toAddress, value, gasLimit, gasPrice, data) tx2 := types.NewTransaction(nonce2, toAddress, value, gasLimit, gasPrice, data) privateKey1, err := crypto.HexToECDSA(from_private_address1) if err != nil { fmt.Println("fail to casting private key to ECDSA") return } privateKey2, err := crypto.HexToECDSA(from_private_address2) if err != nil { fmt.Println("fail to casting private key to ECDSA") return } // sign transaction by private key signedTx1, err := types.SignTx(tx1, chainid, privateKey1) if err != nil { fmt.Println("fail to sign transaction") return } signedTx2, err := types.SignTx(tx2, chainid, privateKey2) if err != nil { fmt.Println("fail to sign transaction") return } // use rlp to encode your transaction body, _ := rlp.EncodeToBytes([]types.Transaction{*signedTx1, *signedTx2}) // encode []byte to string encode_txs := hex.EncodeToString(body) // send raw tx batch by BlockRazor res, err := client.SendTxs(ctx, &pb.SendTxsRequest{Transactions: encode_txs}) if err != nil { fmt.Println("failed to send raw tx batch: ", err) return } else { fmt.Println("raw tx batch sent by BlockRazor, tx hashes are ", res.TxHashs) } } ``` #### Response Example **Success** ```json { "tx_hash":["0xdb95……584813", "0x887d……7aba19"] } ``` **Error** ``` rpc error: code = Unknown desc = invalid transaction format ``` ### **Proto** The code of `relay.proto` is as follows: ``` syntax = "proto3"; package blockchain; option go_package = "/Users/code/relay/grpcServer"; service Gateway { rpc SendTx (SendTxRequest) returns (SendTxReply) {} rpc SendTxs (SendTxsRequest) returns (SendTxsReply) {} rpc NewTxs (TxsRequest) returns (stream TxsReply){} rpc NewBlocks (BlocksRequest) returns (stream BlocksReply){} } message TxsRequest{ bool node_validation = 1; } message Tx{ bytes from = 1; int64 timestamp = 2; bytes raw_tx = 3; } message TxsReply{ Tx tx = 1; } message BlocksRequest{ bool node_validation = 1; } message BlockHeader{ string parent_hash = 1; string sha3_uncles = 2; string miner = 3; string state_root = 4; string transactions_root = 5; string receipts_root = 6; string logs_bloom = 7; string difficulty = 8; string number = 9; uint64 gas_limit = 10; uint64 gas_used = 11; uint64 timestamp = 12; bytes extra_data = 13; string mix_hash = 14; uint64 nonce = 15; uint64 base_fee_per_gas = 16; string withdrawals_root = 17; uint64 blob_gas_used = 18; uint64 excess_blob_gas = 19; string parent_beacon_block_root = 20; } message NextValidator{ string block_height = 1; string coinbase = 2; } message BlocksReply{ string hash = 1; BlockHeader header = 2; repeated NextValidator nextValidator = 3; repeated Tx txs = 4; } message Transaction { string content = 1; } message Transactions { repeated Transaction transactions = 1; } message SendTxRequest { string transaction = 1; } message SendTxsRequest { string transactions = 1; } message SendTxReply { string tx_hash = 1; } message SendTxsReply { repeated string tx_hashs = 1; } ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.blockrazor.io/transaction-submission/fast/bsc/fast-tx.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.