package server import ( "context" "encoding/hex" "encoding/json" "fmt" "math" "net/http" "strconv" "github.com/nspcc-dev/neo-go/config" "github.com/nspcc-dev/neo-go/pkg/core" "github.com/nspcc-dev/neo-go/pkg/core/block" "github.com/nspcc-dev/neo-go/pkg/core/state" "github.com/nspcc-dev/neo-go/pkg/core/transaction" "github.com/nspcc-dev/neo-go/pkg/crypto/hash" "github.com/nspcc-dev/neo-go/pkg/crypto/keys" "github.com/nspcc-dev/neo-go/pkg/encoding/address" "github.com/nspcc-dev/neo-go/pkg/io" "github.com/nspcc-dev/neo-go/pkg/network" "github.com/nspcc-dev/neo-go/pkg/rpc/request" "github.com/nspcc-dev/neo-go/pkg/rpc/response" "github.com/nspcc-dev/neo-go/pkg/rpc/response/result" "github.com/nspcc-dev/neo-go/pkg/smartcontract" "github.com/nspcc-dev/neo-go/pkg/util" "github.com/nspcc-dev/neo-go/pkg/vm/emit" "github.com/pkg/errors" "go.uber.org/zap" ) type ( // Server represents the JSON-RPC 2.0 server. Server struct { *http.Server chain core.Blockchainer config config.RPCConfig coreServer *network.Server log *zap.Logger } ) var invalidBlockHeightError = func(index int, height int) error { return errors.Errorf("Param at index %d should be greater than or equal to 0 and less then or equal to current block height, got: %d", index, height) } // New creates a new Server struct. func New(chain core.Blockchainer, conf config.RPCConfig, coreServer *network.Server, log *zap.Logger) Server { httpServer := &http.Server{ Addr: conf.Address + ":" + strconv.FormatUint(uint64(conf.Port), 10), } return Server{ Server: httpServer, chain: chain, config: conf, coreServer: coreServer, log: log, } } // Start creates a new JSON-RPC server // listening on the configured port. func (s *Server) Start(errChan chan error) { if !s.config.Enabled { s.log.Info("RPC server is not enabled") return } s.Handler = http.HandlerFunc(s.requestHandler) s.log.Info("starting rpc-server", zap.String("endpoint", s.Addr)) errChan <- s.ListenAndServe() } // Shutdown overrides the http.Server Shutdown // method. func (s *Server) Shutdown() error { s.log.Info("shutting down rpc-server", zap.String("endpoint", s.Addr)) return s.Server.Shutdown(context.Background()) } func (s *Server) requestHandler(w http.ResponseWriter, httpRequest *http.Request) { req := request.NewIn() if httpRequest.Method != "POST" { s.WriteErrorResponse( req, w, response.NewInvalidParamsError( fmt.Sprintf("Invalid method '%s', please retry with 'POST'", httpRequest.Method), nil, ), ) return } err := req.DecodeData(httpRequest.Body) if err != nil { s.WriteErrorResponse(req, w, response.NewParseError("Problem parsing JSON-RPC request body", err)) return } reqParams, err := req.Params() if err != nil { s.WriteErrorResponse(req, w, response.NewInvalidParamsError("Problem parsing request parameters", err)) return } s.methodHandler(w, req, *reqParams) } func (s *Server) methodHandler(w http.ResponseWriter, req *request.In, reqParams request.Params) { s.log.Debug("processing rpc request", zap.String("method", req.Method), zap.String("params", fmt.Sprintf("%v", reqParams))) var ( results interface{} resultsErr error ) Methods: switch req.Method { case "getapplicationlog": getapplicationlogCalled.Inc() results, resultsErr = s.getApplicationLog(reqParams) case "getbestblockhash": getbestblockhashCalled.Inc() results = "0x" + s.chain.CurrentBlockHash().StringLE() case "getblock": getbestblockCalled.Inc() var hash util.Uint256 param, ok := reqParams.Value(0) if !ok { resultsErr = response.ErrInvalidParams break Methods } switch param.Type { case request.StringT: var err error hash, err = param.GetUint256() if err != nil { resultsErr = response.ErrInvalidParams break Methods } case request.NumberT: num, err := s.blockHeightFromParam(param) if err != nil { resultsErr = response.ErrInvalidParams break Methods } hash = s.chain.GetHeaderHash(num) default: resultsErr = response.ErrInvalidParams break Methods } block, err := s.chain.GetBlock(hash) if err != nil { resultsErr = response.NewInternalServerError(fmt.Sprintf("Problem locating block with hash: %s", hash), err) break } if len(reqParams) == 2 && reqParams[1].Value == 1 { results = result.NewBlock(block, s.chain) } else { writer := io.NewBufBinWriter() block.EncodeBinary(writer.BinWriter) results = hex.EncodeToString(writer.Bytes()) } case "getblockcount": getblockcountCalled.Inc() results = s.chain.BlockHeight() + 1 case "getblockhash": getblockHashCalled.Inc() param, ok := reqParams.ValueWithType(0, request.NumberT) if !ok { resultsErr = response.ErrInvalidParams break Methods } num, err := s.blockHeightFromParam(param) if err != nil { resultsErr = response.ErrInvalidParams break Methods } results = s.chain.GetHeaderHash(num) case "getblockheader": getblockheaderCalled.Inc() results, resultsErr = s.getBlockHeader(reqParams) case "getblocksysfee": getblocksysfeeCalled.Inc() results, resultsErr = s.getBlockSysFee(reqParams) case "getclaimable": getclaimableCalled.Inc() results, resultsErr = s.getClaimable(reqParams) case "getconnectioncount": getconnectioncountCalled.Inc() results = s.coreServer.PeerCount() case "getnep5balances": getnep5balancesCalled.Inc() results, resultsErr = s.getNEP5Balances(reqParams) case "getnep5transfers": getnep5transfersCalled.Inc() results, resultsErr = s.getNEP5Transfers(reqParams) case "getvalidators": getvalidatorsCalled.Inc() results, resultsErr = s.getValidators() case "getversion": getversionCalled.Inc() results = result.Version{ Port: s.coreServer.Port, Nonce: s.coreServer.ID(), UserAgent: s.coreServer.UserAgent, } case "getpeers": getpeersCalled.Inc() peers := result.NewGetPeers() peers.AddUnconnected(s.coreServer.UnconnectedPeers()) peers.AddConnected(s.coreServer.ConnectedPeers()) peers.AddBad(s.coreServer.BadPeers()) results = peers case "getrawmempool": getrawmempoolCalled.Inc() mp := s.chain.GetMemPool() hashList := make([]util.Uint256, 0) for _, item := range mp.GetVerifiedTransactions() { hashList = append(hashList, item.Tx.Hash()) } results = hashList case "getstorage": getstorageCalled.Inc() results, resultsErr = s.getStorage(reqParams) case "validateaddress": validateaddressCalled.Inc() param, ok := reqParams.Value(0) if !ok { resultsErr = response.ErrInvalidParams break Methods } results = validateAddress(param.Value) case "getassetstate": getassetstateCalled.Inc() param, ok := reqParams.ValueWithType(0, request.StringT) if !ok { resultsErr = response.ErrInvalidParams break Methods } paramAssetID, err := param.GetUint256() if err != nil { resultsErr = response.ErrInvalidParams break } as := s.chain.GetAssetState(paramAssetID) if as != nil { results = result.NewAssetState(as) } else { resultsErr = response.NewRPCError("Unknown asset", "", nil) } case "getaccountstate": getaccountstateCalled.Inc() results, resultsErr = s.getAccountState(reqParams, false) case "getcontractstate": getcontractstateCalled.Inc() results, resultsErr = s.getContractState(reqParams) case "getrawtransaction": getrawtransactionCalled.Inc() results, resultsErr = s.getrawtransaction(reqParams) case "gettransactionheight": gettransactionheightCalled.Inc() results, resultsErr = s.getTransactionHeight(reqParams) case "gettxout": gettxoutCalled.Inc() results, resultsErr = s.getTxOut(reqParams) case "getunclaimed": getunclaimedCalled.Inc() results, resultsErr = s.getUnclaimed(reqParams) case "getunspents": getunspentsCalled.Inc() results, resultsErr = s.getAccountState(reqParams, true) case "invoke": results, resultsErr = s.invoke(reqParams) case "invokefunction": results, resultsErr = s.invokeFunction(reqParams) case "invokescript": results, resultsErr = s.invokescript(reqParams) case "submitblock": submitblockCalled.Inc() results, resultsErr = s.submitBlock(reqParams) case "sendrawtransaction": sendrawtransactionCalled.Inc() results, resultsErr = s.sendrawtransaction(reqParams) default: resultsErr = response.NewMethodNotFoundError(fmt.Sprintf("Method '%s' not supported", req.Method), nil) } if resultsErr != nil { s.WriteErrorResponse(req, w, resultsErr) return } s.WriteResponse(req, w, results) } // getApplicationLog returns the contract log based on the specified txid. func (s *Server) getApplicationLog(reqParams request.Params) (interface{}, error) { param, ok := reqParams.Value(0) if !ok { return nil, response.ErrInvalidParams } txHash, err := param.GetUint256() if err != nil { return nil, response.ErrInvalidParams } appExecResult, err := s.chain.GetAppExecResult(txHash) if err != nil { return nil, response.NewRPCError("Unknown transaction", "", nil) } tx, _, err := s.chain.GetTransaction(txHash) if err != nil { return nil, response.NewRPCError("Error while getting transaction", "", nil) } var scriptHash util.Uint160 switch t := tx.Data.(type) { case *transaction.InvocationTX: scriptHash = hash.Hash160(t.Script) default: return nil, response.NewRPCError("Invalid transaction type", "", nil) } return result.NewApplicationLog(appExecResult, scriptHash), nil } func (s *Server) getClaimable(ps request.Params) (interface{}, error) { p, ok := ps.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } u, err := p.GetUint160FromAddress() if err != nil { return nil, response.ErrInvalidParams } var unclaimed []state.UnclaimedBalance if acc := s.chain.GetAccountState(u); acc != nil { err := acc.Unclaimed.ForEach(func(b *state.UnclaimedBalance) error { unclaimed = append(unclaimed, *b) return nil }) if err != nil { return nil, err } } var sum util.Fixed8 claimable := make([]result.Claimable, 0, len(unclaimed)) for _, ub := range unclaimed { gen, sys, err := s.chain.CalculateClaimable(ub.Value, ub.Start, ub.End) if err != nil { s.log.Info("error while calculating claim bonus", zap.Error(err)) continue } uc := gen.Add(sys) sum += uc claimable = append(claimable, result.Claimable{ Tx: ub.Tx, N: int(ub.Index), Value: ub.Value, StartHeight: ub.Start, EndHeight: ub.End, Generated: gen, SysFee: sys, Unclaimed: uc, }) } return result.ClaimableInfo{ Spents: claimable, Address: p.String(), Unclaimed: sum, }, nil } func (s *Server) getNEP5Balances(ps request.Params) (interface{}, error) { p, ok := ps.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } u, err := p.GetUint160FromHex() if err != nil { return nil, response.ErrInvalidParams } as := s.chain.GetNEP5Balances(u) bs := &result.NEP5Balances{ Address: address.Uint160ToString(u), Balances: []result.NEP5Balance{}, } if as != nil { cache := make(map[util.Uint160]int64) for h, bal := range as.Trackers { dec, err := s.getDecimals(h, cache) if err != nil { continue } amount := amountToString(bal.Balance, dec) bs.Balances = append(bs.Balances, result.NEP5Balance{ Asset: h, Amount: amount, LastUpdated: bal.LastUpdatedBlock, }) } } return bs, nil } func (s *Server) getNEP5Transfers(ps request.Params) (interface{}, error) { p, ok := ps.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } u, err := p.GetUint160FromAddress() if err != nil { return nil, response.ErrInvalidParams } bs := &result.NEP5Transfers{ Address: address.Uint160ToString(u), Received: []result.NEP5Transfer{}, Sent: []result.NEP5Transfer{}, } lg := s.chain.GetNEP5TransferLog(u) cache := make(map[util.Uint160]int64) err = lg.ForEach(func(tr *state.NEP5Transfer) error { transfer := result.NEP5Transfer{ Timestamp: tr.Timestamp, Asset: tr.Asset, Index: tr.Block, TxHash: tr.Tx, } d, err := s.getDecimals(tr.Asset, cache) if err != nil { return nil } if tr.Amount > 0 { // token was received transfer.Amount = amountToString(tr.Amount, d) if !tr.From.Equals(util.Uint160{}) { transfer.Address = address.Uint160ToString(tr.From) } bs.Received = append(bs.Received, transfer) return nil } transfer.Amount = amountToString(-tr.Amount, d) if !tr.From.Equals(util.Uint160{}) { transfer.Address = address.Uint160ToString(tr.To) } bs.Sent = append(bs.Sent, transfer) return nil }) if err != nil { return nil, response.NewInternalServerError("invalid NEP5 transfer log", err) } return bs, nil } func amountToString(amount int64, decimals int64) string { if decimals == 0 { return strconv.FormatInt(amount, 10) } pow := int64(math.Pow10(int(decimals))) q := amount / pow r := amount % pow if r == 0 { return strconv.FormatInt(q, 10) } fs := fmt.Sprintf("%%d.%%0%dd", decimals) return fmt.Sprintf(fs, q, r) } func (s *Server) getDecimals(h util.Uint160, cache map[util.Uint160]int64) (int64, error) { if d, ok := cache[h]; ok { return d, nil } script, err := request.CreateFunctionInvocationScript(h, request.Params{ { Type: request.StringT, Value: "decimals", }, { Type: request.ArrayT, Value: []request.Param{}, }, }) if err != nil { return 0, err } res := s.runScriptInVM(script) if res == nil || res.State != "HALT" || len(res.Stack) == 0 { return 0, errors.New("execution error") } var d int64 switch item := res.Stack[len(res.Stack)-1]; item.Type { case smartcontract.IntegerType: d = item.Value.(int64) case smartcontract.ByteArrayType: d = emit.BytesToInt(item.Value.([]byte)).Int64() default: return 0, errors.New("invalid result") } if d < 0 { return 0, errors.New("negative decimals") } cache[h] = d return d, nil } func (s *Server) getStorage(ps request.Params) (interface{}, error) { param, ok := ps.Value(0) if !ok { return nil, response.ErrInvalidParams } scriptHash, err := param.GetUint160FromHex() if err != nil { return nil, response.ErrInvalidParams } scriptHash = scriptHash.Reverse() param, ok = ps.Value(1) if !ok { return nil, response.ErrInvalidParams } key, err := param.GetBytesHex() if err != nil { return nil, response.ErrInvalidParams } item := s.chain.GetStorageItem(scriptHash.Reverse(), key) if item == nil { return nil, nil } return hex.EncodeToString(item.Value), nil } func (s *Server) getrawtransaction(reqParams request.Params) (interface{}, error) { var resultsErr error var results interface{} if param0, ok := reqParams.Value(0); !ok { return nil, response.ErrInvalidParams } else if txHash, err := param0.GetUint256(); err != nil { resultsErr = response.ErrInvalidParams } else if tx, height, err := s.chain.GetTransaction(txHash); err != nil { err = errors.Wrapf(err, "Invalid transaction hash: %s", txHash) return nil, response.NewRPCError("Unknown transaction", err.Error(), err) } else if len(reqParams) >= 2 { _header := s.chain.GetHeaderHash(int(height)) header, err := s.chain.GetHeader(_header) if err != nil { resultsErr = response.NewInvalidParamsError(err.Error(), err) } param1, _ := reqParams.Value(1) switch v := param1.Value.(type) { case int, float64, bool, string: if v == 0 || v == "0" || v == 0.0 || v == false || v == "false" { results = hex.EncodeToString(tx.Bytes()) } else { results = result.NewTransactionOutputRaw(tx, header, s.chain) } default: results = result.NewTransactionOutputRaw(tx, header, s.chain) } } else { results = hex.EncodeToString(tx.Bytes()) } return results, resultsErr } func (s *Server) getTransactionHeight(ps request.Params) (interface{}, error) { p, ok := ps.Value(0) if !ok { return nil, response.ErrInvalidParams } h, err := p.GetUint256() if err != nil { return nil, response.ErrInvalidParams } _, height, err := s.chain.GetTransaction(h) if err != nil { return nil, response.NewRPCError("unknown transaction", "", nil) } return height, nil } func (s *Server) getTxOut(ps request.Params) (interface{}, error) { p, ok := ps.Value(0) if !ok { return nil, response.ErrInvalidParams } h, err := p.GetUint256() if err != nil { return nil, response.ErrInvalidParams } p, ok = ps.ValueWithType(1, request.NumberT) if !ok { return nil, response.ErrInvalidParams } num, err := p.GetInt() if err != nil || num < 0 { return nil, response.ErrInvalidParams } tx, _, err := s.chain.GetTransaction(h) if err != nil { return nil, response.NewInvalidParamsError(err.Error(), err) } if num >= len(tx.Outputs) { return nil, response.NewInvalidParamsError("invalid index", errors.New("too big index")) } out := tx.Outputs[num] return result.NewTxOutput(&out), nil } // getContractState returns contract state (contract information, according to the contract script hash). func (s *Server) getContractState(reqParams request.Params) (interface{}, error) { var results interface{} param, ok := reqParams.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } else if scriptHash, err := param.GetUint160FromHex(); err != nil { return nil, response.ErrInvalidParams } else { cs := s.chain.GetContractState(scriptHash) if cs != nil { results = result.NewContractState(cs) } else { return nil, response.NewRPCError("Unknown contract", "", nil) } } return results, nil } // getAccountState returns account state either in short or full (unspents included) form. func (s *Server) getAccountState(reqParams request.Params, unspents bool) (interface{}, error) { var resultsErr error var results interface{} param, ok := reqParams.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } else if scriptHash, err := param.GetUint160FromAddress(); err != nil { return nil, response.ErrInvalidParams } else { as := s.chain.GetAccountState(scriptHash) if as == nil { as = state.NewAccount(scriptHash) } if unspents { str, err := param.GetString() if err != nil { return nil, response.ErrInvalidParams } results = result.NewUnspents(as, s.chain, str) } else { results = result.NewAccountState(as) } } return results, resultsErr } // getBlockSysFee returns the system fees of the block, based on the specified index. func (s *Server) getBlockSysFee(reqParams request.Params) (util.Fixed8, error) { param, ok := reqParams.ValueWithType(0, request.NumberT) if !ok { return 0, response.ErrInvalidParams } num, err := s.blockHeightFromParam(param) if err != nil { return 0, response.NewRPCError("Invalid height", "", nil) } headerHash := s.chain.GetHeaderHash(num) block, err := s.chain.GetBlock(headerHash) if err != nil { return 0, response.NewRPCError(err.Error(), "", nil) } var blockSysFee util.Fixed8 for _, tx := range block.Transactions { blockSysFee += s.chain.SystemFee(tx) } return blockSysFee, nil } // getBlockHeader returns the corresponding block header information according to the specified script hash. func (s *Server) getBlockHeader(reqParams request.Params) (interface{}, error) { var verbose bool param, ok := reqParams.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } hash, err := param.GetUint256() if err != nil { return nil, response.ErrInvalidParams } param, ok = reqParams.ValueWithType(1, request.NumberT) if ok { v, err := param.GetInt() if err != nil { return nil, response.ErrInvalidParams } verbose = v != 0 } h, err := s.chain.GetHeader(hash) if err != nil { return nil, response.NewRPCError("unknown block", "", nil) } if verbose { return result.NewHeader(h, s.chain), nil } buf := io.NewBufBinWriter() h.EncodeBinary(buf.BinWriter) if buf.Err != nil { return nil, err } return hex.EncodeToString(buf.Bytes()), nil } // getUnclaimed returns unclaimed GAS amount of the specified address. func (s *Server) getUnclaimed(ps request.Params) (interface{}, error) { p, ok := ps.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } u, err := p.GetUint160FromAddress() if err != nil { return nil, response.ErrInvalidParams } acc := s.chain.GetAccountState(u) if acc == nil { return nil, response.NewInternalServerError("unknown account", nil) } return result.NewUnclaimed(acc, s.chain) } // getValidators returns the current NEO consensus nodes information and voting status. func (s *Server) getValidators() (interface{}, error) { var validators keys.PublicKeys validators, err := s.chain.GetValidators() if err != nil { return nil, err } enrollments, err := s.chain.GetEnrollments() if err != nil { return nil, err } var res []result.Validator for _, v := range enrollments { res = append(res, result.Validator{ PublicKey: *v.PublicKey, Votes: v.Votes, Active: validators.Contains(v.PublicKey), }) } return res, nil } // invoke implements the `invoke` RPC call. func (s *Server) invoke(reqParams request.Params) (interface{}, error) { scriptHashHex, ok := reqParams.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } scriptHash, err := scriptHashHex.GetUint160FromHex() if err != nil { return nil, err } sliceP, ok := reqParams.ValueWithType(1, request.ArrayT) if !ok { return nil, response.ErrInvalidParams } slice, err := sliceP.GetArray() if err != nil { return nil, err } script, err := request.CreateInvocationScript(scriptHash, slice) if err != nil { return nil, err } return s.runScriptInVM(script), nil } // invokescript implements the `invokescript` RPC call. func (s *Server) invokeFunction(reqParams request.Params) (interface{}, error) { scriptHashHex, ok := reqParams.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } scriptHash, err := scriptHashHex.GetUint160FromHex() if err != nil { return nil, err } script, err := request.CreateFunctionInvocationScript(scriptHash, reqParams[1:]) if err != nil { return nil, err } return s.runScriptInVM(script), nil } // invokescript implements the `invokescript` RPC call. func (s *Server) invokescript(reqParams request.Params) (interface{}, error) { if len(reqParams) < 1 { return nil, response.ErrInvalidParams } script, err := reqParams[0].GetBytesHex() if err != nil { return nil, response.ErrInvalidParams } return s.runScriptInVM(script), nil } // runScriptInVM runs given script in a new test VM and returns the invocation // result. func (s *Server) runScriptInVM(script []byte) *result.Invoke { vm, _ := s.chain.GetTestVM() vm.SetGasLimit(s.config.MaxGasInvoke) vm.LoadScript(script) _ = vm.Run() result := &result.Invoke{ State: vm.State(), GasConsumed: vm.GasConsumed().String(), Script: hex.EncodeToString(script), Stack: vm.Estack().ToContractParameters(), } return result } // submitBlock broadcasts a raw block over the NEO network. func (s *Server) submitBlock(reqParams request.Params) (interface{}, error) { param, ok := reqParams.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } blockBytes, err := param.GetBytesHex() if err != nil { return nil, response.ErrInvalidParams } b := block.Block{} r := io.NewBinReaderFromBuf(blockBytes) b.DecodeBinary(r) if r.Err != nil { return nil, response.ErrInvalidParams } err = s.chain.AddBlock(&b) if err != nil { switch err { case core.ErrInvalidBlockIndex, core.ErrAlreadyExists: return nil, response.ErrAlreadyExists default: return nil, response.ErrValidationFailed } } return true, nil } func (s *Server) sendrawtransaction(reqParams request.Params) (interface{}, error) { var resultsErr error var results interface{} if len(reqParams) < 1 { return nil, response.ErrInvalidParams } else if byteTx, err := reqParams[0].GetBytesHex(); err != nil { return nil, response.ErrInvalidParams } else { r := io.NewBinReaderFromBuf(byteTx) tx := &transaction.Transaction{} tx.DecodeBinary(r) if r.Err != nil { return nil, response.ErrInvalidParams } relayReason := s.coreServer.RelayTxn(tx) switch relayReason { case network.RelaySucceed: results = true case network.RelayAlreadyExists: resultsErr = response.ErrAlreadyExists case network.RelayOutOfMemory: resultsErr = response.ErrOutOfMemory case network.RelayUnableToVerify: resultsErr = response.ErrUnableToVerify case network.RelayInvalid: resultsErr = response.ErrValidationFailed case network.RelayPolicyFail: resultsErr = response.ErrPolicyFail default: resultsErr = response.ErrUnknown } } return results, resultsErr } func (s *Server) blockHeightFromParam(param *request.Param) (int, error) { num, err := param.GetInt() if err != nil { return 0, nil } if num < 0 || num > int(s.chain.BlockHeight()) { return 0, invalidBlockHeightError(0, num) } return num, nil } // WriteErrorResponse writes an error response to the ResponseWriter. func (s *Server) WriteErrorResponse(r *request.In, w http.ResponseWriter, err error) { jsonErr, ok := err.(*response.Error) if !ok { jsonErr = response.NewInternalServerError("Internal server error", err) } resp := response.Raw{ HeaderAndError: response.HeaderAndError{ Header: response.Header{ JSONRPC: r.JSONRPC, ID: r.RawID, }, Error: jsonErr, }, } logFields := []zap.Field{ zap.Error(jsonErr.Cause), zap.String("method", r.Method), } params, err := r.Params() if err == nil { logFields = append(logFields, zap.Any("params", params)) } s.log.Error("Error encountered with rpc request", logFields...) w.WriteHeader(jsonErr.HTTPCode) s.writeServerResponse(r, w, resp) } // WriteResponse encodes the response and writes it to the ResponseWriter. func (s *Server) WriteResponse(r *request.In, w http.ResponseWriter, result interface{}) { resJSON, err := json.Marshal(result) if err != nil { s.log.Error("Error encountered while encoding response", zap.String("err", err.Error()), zap.String("method", r.Method)) return } resp := response.Raw{ HeaderAndError: response.HeaderAndError{ Header: response.Header{ JSONRPC: r.JSONRPC, ID: r.RawID, }, }, Result: resJSON, } s.writeServerResponse(r, w, resp) } func (s *Server) writeServerResponse(r *request.In, w http.ResponseWriter, resp response.Raw) { w.Header().Set("Content-Type", "application/json; charset=utf-8") if s.config.EnableCORSWorkaround { w.Header().Set("Access-Control-Allow-Origin", "*") w.Header().Set("Access-Control-Allow-Headers", "Content-Type, Access-Control-Allow-Headers, Authorization, X-Requested-With") } encoder := json.NewEncoder(w) err := encoder.Encode(resp) if err != nil { s.log.Error("Error encountered while encoding response", zap.String("err", err.Error()), zap.String("method", r.Method)) } } // validateAddress verifies that the address is a correct NEO address // see https://docs.neo.org/en-us/node/cli/2.9.4/api/validateaddress.html func validateAddress(addr interface{}) result.ValidateAddress { resp := result.ValidateAddress{Address: addr} if addr, ok := addr.(string); ok { _, err := address.StringToUint160(addr) resp.IsValid = (err == nil) } return resp }