github.com/MetalBlockchain/subnet-evm@v0.4.9/plugin/evm/log.go (about)

     1  // (c) 2019-2020, Ava Labs, Inc. All rights reserved.
     2  // See the file LICENSE for licensing terms.
     3  
     4  package evm
     5  
     6  import (
     7  	"encoding/json"
     8  	"fmt"
     9  	"io"
    10  	"reflect"
    11  	"time"
    12  
    13  	"github.com/ethereum/go-ethereum/log"
    14  )
    15  
    16  const (
    17  	errorKey   = "LOG15_ERROR"
    18  	timeFormat = "2006-01-02T15:04:05-0700"
    19  )
    20  
    21  type SubnetEVMLogger struct {
    22  	log.Handler
    23  }
    24  
    25  // InitLogger initializes logger with alias and sets the log level and format with the original [os.StdErr] interface
    26  // along with the context logger.
    27  func InitLogger(alias string, level string, jsonFormat bool, writer io.Writer) (SubnetEVMLogger, error) {
    28  	logFormat := SubnetEVMTermFormat(alias)
    29  	if jsonFormat {
    30  		logFormat = SubnetEVMJSONFormat(alias)
    31  	}
    32  
    33  	// Create handler
    34  	logHandler := log.StreamHandler(writer, logFormat)
    35  	c := SubnetEVMLogger{Handler: logHandler}
    36  
    37  	if err := c.SetLogLevel(level); err != nil {
    38  		return SubnetEVMLogger{}, err
    39  	}
    40  	return c, nil
    41  }
    42  
    43  // SetLogLevel sets the log level of initialized log handler.
    44  func (c *SubnetEVMLogger) SetLogLevel(level string) error {
    45  	// Set log level
    46  	logLevel, err := log.LvlFromString(level)
    47  	if err != nil {
    48  		return err
    49  	}
    50  	log.Root().SetHandler(log.LvlFilterHandler(logLevel, c))
    51  	return nil
    52  }
    53  
    54  func SubnetEVMTermFormat(alias string) log.Format {
    55  	prefix := fmt.Sprintf("<%s Chain>", alias)
    56  	return log.FormatFunc(func(r *log.Record) []byte {
    57  		location := fmt.Sprintf("%+v", r.Call)
    58  		newMsg := fmt.Sprintf("%s %s: %s", prefix, location, r.Msg)
    59  		r.Msg = newMsg
    60  		return log.TerminalFormat(false).Format(r)
    61  	})
    62  }
    63  
    64  func SubnetEVMJSONFormat(alias string) log.Format {
    65  	prefix := fmt.Sprintf("%s Chain", alias)
    66  	return log.FormatFunc(func(r *log.Record) []byte {
    67  		props := make(map[string]interface{}, 5+len(r.Ctx)/2)
    68  		props["timestamp"] = r.Time
    69  		props["level"] = r.Lvl.String()
    70  		props[r.KeyNames.Msg] = r.Msg
    71  		props["logger"] = prefix
    72  		props["caller"] = fmt.Sprintf("%+v", r.Call)
    73  		for i := 0; i < len(r.Ctx); i += 2 {
    74  			k, ok := r.Ctx[i].(string)
    75  			if !ok {
    76  				props[errorKey] = fmt.Sprintf("%+v is not a string key", r.Ctx[i])
    77  			} else {
    78  				// The number of arguments is normalized from the geth logger
    79  				// to ensure that this will not cause an index out of bounds error
    80  				props[k] = formatJSONValue(r.Ctx[i+1])
    81  			}
    82  		}
    83  
    84  		b, err := json.Marshal(props)
    85  		if err != nil {
    86  			b, _ = json.Marshal(map[string]string{
    87  				errorKey: err.Error(),
    88  			})
    89  			return b
    90  		}
    91  
    92  		b = append(b, '\n')
    93  		return b
    94  	})
    95  }
    96  
    97  func formatJSONValue(value interface{}) (result interface{}) {
    98  	defer func() {
    99  		if err := recover(); err != nil {
   100  			if v := reflect.ValueOf(value); v.Kind() == reflect.Ptr && v.IsNil() {
   101  				result = "nil"
   102  			} else {
   103  				panic(err)
   104  			}
   105  		}
   106  	}()
   107  
   108  	switch v := value.(type) {
   109  	case time.Time:
   110  		return v.Format(timeFormat)
   111  
   112  	case error:
   113  		return v.Error()
   114  
   115  	case fmt.Stringer:
   116  		return v.String()
   117  
   118  	default:
   119  		return v
   120  	}
   121  }