github.com/pranksteess/go-ethereum@v1.9.7/core/vm/logger_json.go (about)

     1  // Copyright 2017 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package vm
    18  
    19  import (
    20  	"encoding/json"
    21  	"io"
    22  	"math/big"
    23  	"time"
    24  
    25  	"github.com/ethereum/go-ethereum/common"
    26  	"github.com/ethereum/go-ethereum/common/math"
    27  )
    28  
    29  type JSONLogger struct {
    30  	encoder *json.Encoder
    31  	cfg     *LogConfig
    32  }
    33  
    34  // NewJSONLogger creates a new EVM tracer that prints execution steps as JSON objects
    35  // into the provided stream.
    36  func NewJSONLogger(cfg *LogConfig, writer io.Writer) *JSONLogger {
    37  	l := &JSONLogger{json.NewEncoder(writer), cfg}
    38  	if l.cfg == nil {
    39  		l.cfg = &LogConfig{}
    40  	}
    41  	return l
    42  }
    43  
    44  func (l *JSONLogger) CaptureStart(from common.Address, to common.Address, create bool, input []byte, gas uint64, value *big.Int) error {
    45  	return nil
    46  }
    47  
    48  // CaptureState outputs state information on the logger.
    49  func (l *JSONLogger) CaptureState(env *EVM, pc uint64, op OpCode, gas, cost uint64, memory *Memory, stack *Stack, contract *Contract, depth int, err error) error {
    50  	log := StructLog{
    51  		Pc:            pc,
    52  		Op:            op,
    53  		Gas:           gas,
    54  		GasCost:       cost,
    55  		MemorySize:    memory.Len(),
    56  		Storage:       nil,
    57  		Depth:         depth,
    58  		RefundCounter: env.StateDB.GetRefund(),
    59  		Err:           err,
    60  	}
    61  	if !l.cfg.DisableMemory {
    62  		log.Memory = memory.Data()
    63  	}
    64  	if !l.cfg.DisableStack {
    65  		log.Stack = stack.Data()
    66  	}
    67  	return l.encoder.Encode(log)
    68  }
    69  
    70  // CaptureFault outputs state information on the logger.
    71  func (l *JSONLogger) CaptureFault(env *EVM, pc uint64, op OpCode, gas, cost uint64, memory *Memory, stack *Stack, contract *Contract, depth int, err error) error {
    72  	return nil
    73  }
    74  
    75  // CaptureEnd is triggered at end of execution.
    76  func (l *JSONLogger) CaptureEnd(output []byte, gasUsed uint64, t time.Duration, err error) error {
    77  	type endLog struct {
    78  		Output  string              `json:"output"`
    79  		GasUsed math.HexOrDecimal64 `json:"gasUsed"`
    80  		Time    time.Duration       `json:"time"`
    81  		Err     string              `json:"error,omitempty"`
    82  	}
    83  	if err != nil {
    84  		return l.encoder.Encode(endLog{common.Bytes2Hex(output), math.HexOrDecimal64(gasUsed), t, err.Error()})
    85  	}
    86  	return l.encoder.Encode(endLog{common.Bytes2Hex(output), math.HexOrDecimal64(gasUsed), t, ""})
    87  }