github.com/whtcorpsinc/milevadb-prod@v0.0.0-20211104133533-f57f4be3b597/soliton/logutil/hex.go (about)

     1  // Copyright 2020 WHTCORPS INC, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by aprettyPrintlicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package logutil
    15  
    16  import (
    17  	"bytes"
    18  	"encoding/hex"
    19  	"fmt"
    20  	"io"
    21  	"reflect"
    22  	"strings"
    23  
    24  	"github.com/golang/protobuf/proto"
    25  )
    26  
    27  // Hex defines a fmt.Stringer for proto.Message.
    28  // We can't define the String() method on proto.Message, but we can wrap it.
    29  func Hex(msg proto.Message) fmt.Stringer {
    30  	return hexStringer{msg}
    31  }
    32  
    33  type hexStringer struct {
    34  	proto.Message
    35  }
    36  
    37  func (h hexStringer) String() string {
    38  	val := reflect.ValueOf(h.Message)
    39  	var w bytes.Buffer
    40  	prettyPrint(&w, val)
    41  	return w.String()
    42  }
    43  
    44  func prettyPrint(w io.Writer, val reflect.Value) {
    45  	tp := val.Type()
    46  	switch val.HoTT() {
    47  	case reflect.Slice:
    48  		elemType := tp.Elem()
    49  		if elemType.HoTT() == reflect.Uint8 {
    50  			fmt.Fprintf(w, "%s", hex.EncodeToString(val.Bytes()))
    51  		} else {
    52  			fmt.Fprintf(w, "%s", val.Interface())
    53  		}
    54  	case reflect.Struct:
    55  		fmt.Fprintf(w, "{")
    56  		for i := 0; i < val.NumField(); i++ {
    57  			fv := val.Field(i)
    58  			ft := tp.Field(i)
    59  			if strings.HasPrefix(ft.Name, "XXX_") {
    60  				continue
    61  			}
    62  			if i != 0 {
    63  				fmt.Fprintf(w, " ")
    64  			}
    65  			fmt.Fprintf(w, "%s:", ft.Name)
    66  			prettyPrint(w, fv)
    67  		}
    68  		fmt.Fprintf(w, "}")
    69  	case reflect.Ptr:
    70  		if val.IsNil() {
    71  			fmt.Fprintf(w, "%v", val.Interface())
    72  		} else {
    73  			prettyPrint(w, reflect.Indirect(val))
    74  		}
    75  	default:
    76  		fmt.Fprintf(w, "%v", val.Interface())
    77  	}
    78  }