Implement a command for load testing with predefined JSON-RPC API calls

Author: m-Peter

cmd/load_test/cmd.go

@@ -0,0 +1,271 @@
+package load_test
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"math/big"
+	"math/rand"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/rs/zerolog/log"
+	"github.com/spf13/cobra"
+	"golang.org/x/sync/errgroup"
+)
+
+var Cmd = &cobra.Command{
+	Use:   "load_test",
+	Short: "Simulates API traffic on an EVM Gateway node for load testing purposes",
+	RunE: func(command *cobra.Command, _ []string) error {
+		ctx, cancel := context.WithCancel(command.Context())
+		defer cancel()
+
+		g := errgroup.Group{}
+		for range workers {
+			g.Go(func() error {
+				for ctx.Err() == nil {
+					err := simulateTraffic()
+					if err != nil {
+						fmt.Println("Error: ", err)
+					}
+				}
+
+				return nil
+			})
+		}
+
+		osSig := make(chan os.Signal, 1)
+		signal.Notify(osSig, syscall.SIGINT, syscall.SIGTERM)
+
+		// wait for command to exit or for a shutdown signal
+		<-osSig
+		log.Info().Msg("OS Signal to shutdown received, shutting down")
+		cancel()
+
+		return nil
+	},
+}
+
+func simulateTraffic() error {
+	rpcClient := &RpcClient{url: evmGatewayHost}
+
+	blockNumber, err := rpcClient.EthBlockNumber()
+	if err != nil {
+		return fmt.Errorf("failed to call `eth_blockNumber`: %w", err)
+	}
+	fmt.Println("Block Number: ", blockNumber)
+
+	block, err := rpcClient.EthGetBlockByNumber(blockNumber)
+	if err != nil {
+		return fmt.Errorf("failed to call `eth_getBlockByNumber`: %w", err)
+	}
+	fmt.Println("Block: ", block)
+
+	blockReceipts, err := rpcClient.EthGetBlockReceipts(blockNumber)
+	if err != nil {
+		return fmt.Errorf("failed to call `eth_getBlockReceipts`: %w", err)
+	}
+	fmt.Println("Block Receipts: ", blockReceipts)
+
+	if len(blockReceipts) > 0 {
+		receipt := blockReceipts[rand.Intn(len(blockReceipts))]
+		if val, ok := receipt["transactionHash"]; ok {
+			txHash := val.(string)
+			receipt, err := rpcClient.EthGetReceipt(txHash)
+			if err != nil {
+				return fmt.Errorf("failed to call `eth_getTransactionReceipt`: %w", err)
+			}
+			fmt.Println("Receipt: ", receipt)
+
+			txTrace, err := rpcClient.DebugTraceTransaction(txHash)
+			if err != nil {
+				return fmt.Errorf("failed to call `debug_TraceTransaction`: %w", err)
+			}
+			fmt.Println("Tx Trace: ", txTrace)
+		}
+
+		if val, ok := receipt["from"]; ok {
+			from := val.(string)
+			balance, err := rpcClient.EthGetBalance(from)
+			if err != nil {
+				return fmt.Errorf("failed to call `eth_getBalance`: %w", err)
+			}
+			fmt.Println("Balance: ", balance)
+		}
+	}
+
+	blockTraces, err := rpcClient.DebugTraceBlockByNumber(blockNumber)
+	if err != nil {
+		return fmt.Errorf("failed to call `debug_traceBlockByNumber`: %w", err)
+	}
+	fmt.Println("Block Traces: ", blockTraces)
+
+	callResult, err := rpcClient.EthCall()
+	if err != nil {
+		return fmt.Errorf("failed to call `eth_call`: %w", err)
+	}
+	fmt.Println("Call Result: ", callResult)
+
+	return nil
+}
+
+type RpcResult struct {
+	Result json.RawMessage `json:"result"`
+	Error  any             `json:"error"`
+}
+
+type RpcClient struct {
+	url string
+}
+
+func (r *RpcClient) request(method string, params string) (json.RawMessage, error) {
+	requestURL := fmt.Sprintf(`{"jsonrpc":"2.0","id":0,"method":"%s","params":%s}`, method, params)
+	body := bytes.NewReader([]byte(requestURL))
+	req, err := http.NewRequest(http.MethodPost, r.url, body)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("content-type", "application/json")
+	req.Header.Set("accept-encoding", "identity")
+
+	res, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	content, err := io.ReadAll(res.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	var resp RpcResult
+	err = json.Unmarshal(content, &resp)
+	if err != nil {
+		return nil, err
+	}
+	if resp.Error != nil {
+		return nil, fmt.Errorf("%s", resp.Error)
+	}
+
+	return resp.Result, nil
+}
+
+func (r *RpcClient) EthBlockNumber() (string, error) {
+	rpcRes, err := r.request("eth_blockNumber", "[]")
+	if err != nil {
+		return "", err
+	}
+
+	var blockNumber string
+	err = json.Unmarshal(rpcRes, &blockNumber)
+	if err != nil {
+		return "", err
+	}
+
+	return blockNumber, nil
+}
+
+func (r *RpcClient) EthGetBlockByNumber(blockNumber string) (string, error) {
+	rpcRes, err := r.request("eth_getBlockByNumber", fmt.Sprintf(`["%s",true]`, blockNumber))
+	if err != nil {
+		return "", err
+	}
+
+	return string(rpcRes), nil
+}
+
+func (r *RpcClient) EthGetBlockReceipts(blockNumber string) ([]map[string]any, error) {
+	rpcRes, err := r.request("eth_getBlockReceipts", fmt.Sprintf(`["%s"]`, blockNumber))
+	if err != nil {
+		return nil, err
+	}
+
+	var blockReceipts []map[string]any
+	err = json.Unmarshal(rpcRes, &blockReceipts)
+	if err != nil {
+		return nil, err
+	}
+
+	return blockReceipts, nil
+}
+
+func (r *RpcClient) DebugTraceBlockByNumber(blockNumber string) (string, error) {
+	tracerConfig := `{"tracer":"callTracer","tracerConfig":{"withLog":true,"onlyTopCall":false}}`
+	rpcRes, err := r.request("debug_traceBlockByNumber", fmt.Sprintf(`["%s",%s]`, blockNumber, tracerConfig))
+	if err != nil {
+		return "", err
+	}
+
+	return string(rpcRes), nil
+}
+
+func (r *RpcClient) DebugTraceTransaction(txHash string) (string, error) {
+	tracerConfig := `{"tracer":"callTracer","tracerConfig":{"withLog":true,"onlyTopCall":false}}`
+	rpcRes, err := r.request("debug_traceTransaction", fmt.Sprintf(`["%s",%s]`, txHash, tracerConfig))
+	if err != nil {
+		return "", err
+	}
+
+	return string(rpcRes), nil
+}
+
+func (r *RpcClient) EthGetBalance(address string) (*big.Int, error) {
+	balanceRes, err := r.request("eth_getBalance", fmt.Sprintf(`["%s", "latest"]`, address))
+	if err != nil {
+		return nil, err
+	}
+
+	var balance hexutil.Big
+	err = json.Unmarshal(balanceRes, &balance)
+	if err != nil {
+		return nil, err
+	}
+
+	return balance.ToInt(), nil
+}
+
+func (r *RpcClient) EthGetReceipt(hash string) (*types.Receipt, error) {
+	rpcRes, err := r.request("eth_getTransactionReceipt", fmt.Sprintf(`["%s"]`, hash))
+	if err != nil {
+		return nil, err
+	}
+
+	var rcp types.Receipt
+	err = json.Unmarshal(rpcRes, &rcp)
+	if err != nil {
+		return nil, err
+	}
+
+	return &rcp, nil
+}
+
+func (r *RpcClient) EthCall() (string, error) {
+	callParams := `{"from":"0x980DbdE8EC2cFebFA46660778afC1cc182EaEADa","to":"0xf19fD4347CafAdd409a9fA090b3AD068272035a1","gas":"0x3CFA39","value":"0x0","input":"0x5148e0ba00000000000000000000000000000000000000000000006c6b935b8bbd400000000000000000000000000000000000000000000000000000000000000000037800000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000000"}`
+	rpcRes, err := r.request("eth_call", fmt.Sprintf(`[%s,"latest"]`, callParams))
+	if err != nil {
+		return "", err
+	}
+
+	return string(rpcRes), nil
+}
+
+var (
+	evmGatewayHost string
+	workers        int
+)
+
+func init() {
+	Cmd.Flags().StringVar(&evmGatewayHost, "evm-gw-host", "http://127.0.0.1:8545", "EVM Gateway host against which to run the load test")
+	Cmd.Flags().IntVar(&workers, "workers", 10, "Number of workers to use for concurrent JSON-RPC requests")
+
+	if err := Cmd.MarkFlagRequired("evm-gw-host"); err != nil {
+		panic(err)
+	}
+}

cmd/main.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/onflow/flow-evm-gateway/cmd/blocks"
 	"github.com/onflow/flow-evm-gateway/cmd/export"
+	"github.com/onflow/flow-evm-gateway/cmd/load_test"
 	"github.com/onflow/flow-evm-gateway/cmd/run"
 	"github.com/onflow/flow-evm-gateway/cmd/version"
 	"github.com/rs/zerolog/log"
@@ -28,6 +29,7 @@ func main() {
 	rootCmd.AddCommand(export.Cmd)
 	rootCmd.AddCommand(blocks.Cmd)
 	rootCmd.AddCommand(run.Cmd)
+	rootCmd.AddCommand(load_test.Cmd)
 
 	Execute()
 }