Avoid logging debug info for invalid JSON-RPC methods

api/api.go

@@ -32,6 +32,67 @@ import (
 
 const maxFeeHistoryBlockCount = 1024
 
+// A map containing all the valid method names that are found
+// in the Ethereum JSON-RPC API specification.
+// Update accordingly if any new methods are added/removed.
+var validMethods = map[string]struct{}{
+	// eth namespace
+	"eth_blockNumber":                         {},
+	"eth_syncing":                             {},
+	"eth_sendRawTransaction":                  {},
+	"eth_getBalance":                          {},
+	"eth_getTransactionByHash":                {},
+	"eth_getTransactionByBlockHashAndIndex":   {},
+	"eth_getTransactionByBlockNumberAndIndex": {},
+	"eth_getTransactionReceipt":               {},
+	"eth_getBlockByHash":                      {},
+	"eth_getBlockByNumber":                    {},
+	"eth_getBlockReceipts":                    {},
+	"eth_getBlockTransactionCountByHash":      {},
+	"eth_getBlockTransactionCountByNumber":    {},
+	"eth_call":                                {},
+	"eth_getLogs":                             {},
+	"eth_getTransactionCount":                 {},
+	"eth_estimateGas":                         {},
+	"eth_getCode":                             {},
+	"eth_feeHistory":                          {},
+	"eth_getStorageAt":                        {},
+	"eth_chainId":                             {},
+	"eth_coinbase":                            {},
+	"eth_gasPrice":                            {},
+	"eth_getUncleCountByBlockHash":            {},
+	"eth_getUncleCountByBlockNumber":          {},
+	"eth_getUncleByBlockHashAndIndex":         {},
+	"eth_getUncleByBlockNumberAndIndex":       {},
+	"eth_maxPriorityFeePerGas":                {},
+	"eth_mining":                              {},
+	"eth_hashrate":                            {},
+	"eth_getProof":                            {},
+	"eth_createAccessList":                    {},
+
+	// web3 namespace
+	"web3_clientVersion": {},
+	"web3_sha3":          {},
+
+	// net namespace
+	"net_listening": {},
+	"net_peerCount": {},
+	"net_version":   {},
+
+	// txpool namespace
+	"txpool_content":     {},
+	"txpool_contentFrom": {},
+	"txpool_status":      {},
+	"txpool_inspect":     {},
+}
+
+// Returns whether the given method name is a valid method from
+// the Ethereum JSON-RPC API specification.
+func IsValidMethod(methodName string) bool {
+	_, ok := validMethods[methodName]
+	return ok
+}
+
 var latestBlockNumberOrHash = rpc.BlockNumberOrHashWithNumber(rpc.LatestBlockNumber)
 
 func SupportedAPIs(

api/server.go

@@ -246,16 +246,22 @@ func (h *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 
 	requestBody := make(map[string]any)
-	// Check if WebSocket request and serve if JSON-RPC over WebSocket is enabled
 	if b, err := io.ReadAll(r.Body); err == nil {
 		_ = json.Unmarshal(b, &requestBody)
 
-		h.logger.Debug().
-			Str("IP", r.RemoteAddr).
-			Str("url", r.URL.String()).
-			Fields(requestBody).
-			Bool("is-ws", isWebSocket(r)).
-			Msg("API request")
+		// Do not log any debug info for methods that are not valid
+		// JSON-RPC methods.
+		if methodValue, ok := requestBody["method"]; ok {
+			if methodStr, ok := methodValue.(string); ok && IsValidMethod(methodStr) {
+				h.logger.Debug().
+					Str("IP", r.RemoteAddr).
+					Str("url", r.URL.String()).
+					Fields(requestBody).
+					Bool("is-ws", isWebSocket(r)).
+					Msg("API request")
+
+			}
+		}
 
 		r.Body = io.NopCloser(bytes.NewBuffer(b))
 		r.Body.Close()
@@ -270,6 +276,7 @@ func (h *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 
 	ws := h.wsHandler
+	// Check if WebSocket request and serve if JSON-RPC over WebSocket is enabled
 	if ws != nil && isWebSocket(r) {
 		ws.ServeHTTP(w, r)
 		return
@@ -480,7 +487,10 @@ func (w *responseHandler) Write(data []byte) (int, error) {
 	if message.Error == nil {
 		r, _ := message.Result.MarshalJSON()
 		log.RawJSON("result", r).Msg("API response")
-	} else { // still debug output all errors even known ones
+	}
+
+	// still debug output all errors even known ones
+	if message.Error != nil && message.Error.Code != errMethodNotFound {
 		l.Debug().
 			Str("error", message.Error.Message).
 			Int("code", message.Error.Code).