go-ethereum/log/format.go

370 lines
9.1 KiB
Go

package log
import (
"bytes"
"fmt"
"math/big"
"reflect"
"strconv"
"time"
"unicode/utf8"
"github.com/holiman/uint256"
"golang.org/x/exp/slog"
)
const (
timeFormat = "2006-01-02T15:04:05-0700"
floatFormat = 'f'
termMsgJust = 40
termCtxMaxPadding = 40
)
// 40 spaces
var spaces = []byte(" ")
// TerminalStringer is an analogous interface to the stdlib stringer, allowing
// own types to have custom shortened serialization formats when printed to the
// screen.
type TerminalStringer interface {
TerminalString() string
}
func (h *TerminalHandler) format(buf []byte, r slog.Record, usecolor bool) []byte {
msg := escapeMessage(r.Message)
var color = ""
if usecolor {
switch r.Level {
case LevelCrit:
color = "\x1b[35m"
case slog.LevelError:
color = "\x1b[31m"
case slog.LevelWarn:
color = "\x1b[33m"
case slog.LevelInfo:
color = "\x1b[32m"
case slog.LevelDebug:
color = "\x1b[36m"
case LevelTrace:
color = "\x1b[34m"
}
}
if buf == nil {
buf = make([]byte, 0, 30+termMsgJust)
}
b := bytes.NewBuffer(buf)
if color != "" { // Start color
b.WriteString(color)
b.WriteString(LevelAlignedString(r.Level))
b.WriteString("\x1b[0m")
} else {
b.WriteString(LevelAlignedString(r.Level))
}
b.WriteString("[")
writeTimeTermFormat(b, r.Time)
b.WriteString("] ")
b.WriteString(msg)
// try to justify the log output for short messages
//length := utf8.RuneCountInString(msg)
length := len(msg)
if (r.NumAttrs()+len(h.attrs)) > 0 && length < termMsgJust {
b.Write(spaces[:termMsgJust-length])
}
// print the attributes
h.formatAttributes(b, r, color)
return b.Bytes()
}
func (h *TerminalHandler) formatAttributes(buf *bytes.Buffer, r slog.Record, color string) {
// tmp is a temporary buffer we use, until bytes.Buffer.AvailableBuffer() (1.21)
// can be used.
var tmp = make([]byte, 40)
writeAttr := func(attr slog.Attr, first, last bool) {
buf.WriteByte(' ')
if color != "" {
buf.WriteString(color)
//buf.Write(appendEscapeString(buf.AvailableBuffer(), attr.Key))
buf.Write(appendEscapeString(tmp[:0], attr.Key))
buf.WriteString("\x1b[0m=")
} else {
//buf.Write(appendEscapeString(buf.AvailableBuffer(), attr.Key))
buf.Write(appendEscapeString(tmp[:0], attr.Key))
buf.WriteByte('=')
}
//val := FormatSlogValue(attr.Value, true, buf.AvailableBuffer())
val := FormatSlogValue(attr.Value, tmp[:0])
padding := h.fieldPadding[attr.Key]
length := utf8.RuneCount(val)
if padding < length && length <= termCtxMaxPadding {
padding = length
h.fieldPadding[attr.Key] = padding
}
buf.Write(val)
if !last && padding > length {
buf.Write(spaces[:padding-length])
}
}
var n = 0
var nAttrs = len(h.attrs) + r.NumAttrs()
for _, attr := range h.attrs {
writeAttr(attr, n == 0, n == nAttrs-1)
n++
}
r.Attrs(func(attr slog.Attr) bool {
writeAttr(attr, n == 0, n == nAttrs-1)
n++
return true
})
buf.WriteByte('\n')
}
// FormatSlogValue formats a slog.Value for serialization to terminal.
func FormatSlogValue(v slog.Value, tmp []byte) (result []byte) {
var value any
defer func() {
if err := recover(); err != nil {
if v := reflect.ValueOf(value); v.Kind() == reflect.Ptr && v.IsNil() {
result = []byte("<nil>")
} else {
panic(err)
}
}
}()
switch v.Kind() {
case slog.KindString:
return appendEscapeString(tmp, v.String())
case slog.KindInt64: // All int-types (int8, int16 etc) wind up here
return appendInt64(tmp, v.Int64())
case slog.KindUint64: // All uint-types (uint8, uint16 etc) wind up here
return appendUint64(tmp, v.Uint64(), false)
case slog.KindFloat64:
return strconv.AppendFloat(tmp, v.Float64(), floatFormat, 3, 64)
case slog.KindBool:
return strconv.AppendBool(tmp, v.Bool())
case slog.KindDuration:
value = v.Duration()
case slog.KindTime:
// Performance optimization: No need for escaping since the provided
// timeFormat doesn't have any escape characters, and escaping is
// expensive.
return v.Time().AppendFormat(tmp, timeFormat)
default:
value = v.Any()
}
if value == nil {
return []byte("<nil>")
}
switch v := value.(type) {
case *big.Int: // Need to be before fmt.Stringer-clause
return appendBigInt(tmp, v)
case *uint256.Int: // Need to be before fmt.Stringer-clause
return appendU256(tmp, v)
case error:
return appendEscapeString(tmp, v.Error())
case TerminalStringer:
return appendEscapeString(tmp, v.TerminalString())
case fmt.Stringer:
return appendEscapeString(tmp, v.String())
}
// We can use the 'tmp' as a scratch-buffer, to first format the
// value, and in a second step do escaping.
internal := fmt.Appendf(tmp, "%+v", value)
return appendEscapeString(tmp, string(internal))
}
// appendInt64 formats n with thousand separators and writes into buffer dst.
func appendInt64(dst []byte, n int64) []byte {
if n < 0 {
return appendUint64(dst, uint64(-n), true)
}
return appendUint64(dst, uint64(n), false)
}
// appendUint64 formats n with thousand separators and writes into buffer dst.
func appendUint64(dst []byte, n uint64, neg bool) []byte {
// Small numbers are fine as is
if n < 100000 {
if neg {
return strconv.AppendInt(dst, -int64(n), 10)
} else {
return strconv.AppendInt(dst, int64(n), 10)
}
}
// Large numbers should be split
const maxLength = 26
var (
out = make([]byte, maxLength)
i = maxLength - 1
comma = 0
)
for ; n > 0; i-- {
if comma == 3 {
comma = 0
out[i] = ','
} else {
comma++
out[i] = '0' + byte(n%10)
n /= 10
}
}
if neg {
out[i] = '-'
i--
}
return append(dst, out[i+1:]...)
}
// FormatLogfmtUint64 formats n with thousand separators.
func FormatLogfmtUint64(n uint64) string {
return string(appendUint64(nil, n, false))
}
// appendBigInt formats n with thousand separators and writes to dst.
func appendBigInt(dst []byte, n *big.Int) []byte {
if n.IsUint64() {
return appendUint64(dst, n.Uint64(), false)
}
if n.IsInt64() {
return appendInt64(dst, n.Int64())
}
var (
text = n.String()
buf = make([]byte, len(text)+len(text)/3)
comma = 0
i = len(buf) - 1
)
for j := len(text) - 1; j >= 0; j, i = j-1, i-1 {
c := text[j]
switch {
case c == '-':
buf[i] = c
case comma == 3:
buf[i] = ','
i--
comma = 0
fallthrough
default:
buf[i] = c
comma++
}
}
return append(dst, buf[i+1:]...)
}
// appendU256 formats n with thousand separators.
func appendU256(dst []byte, n *uint256.Int) []byte {
if n.IsUint64() {
return appendUint64(dst, n.Uint64(), false)
}
res := []byte(n.PrettyDec(','))
return append(dst, res...)
}
// appendEscapeString writes the string s to the given writer, with
// escaping/quoting if needed.
func appendEscapeString(dst []byte, s string) []byte {
needsQuoting := false
needsEscaping := false
for _, r := range s {
// If it contains spaces or equal-sign, we need to quote it.
if r == ' ' || r == '=' {
needsQuoting = true
continue
}
// We need to escape it, if it contains
// - character " (0x22) and lower (except space)
// - characters above ~ (0x7E), plus equal-sign
if r <= '"' || r > '~' {
needsEscaping = true
break
}
}
if needsEscaping {
return strconv.AppendQuote(dst, s)
}
// No escaping needed, but we might have to place within quote-marks, in case
// it contained a space
if needsQuoting {
dst = append(dst, '"')
dst = append(dst, []byte(s)...)
return append(dst, '"')
}
return append(dst, []byte(s)...)
}
// escapeMessage checks if the provided string needs escaping/quoting, similarly
// to escapeString. The difference is that this method is more lenient: it allows
// for spaces and linebreaks to occur without needing quoting.
func escapeMessage(s string) string {
needsQuoting := false
for _, r := range s {
// Allow CR/LF/TAB. This is to make multi-line messages work.
if r == '\r' || r == '\n' || r == '\t' {
continue
}
// We quote everything below <space> (0x20) and above~ (0x7E),
// plus equal-sign
if r < ' ' || r > '~' || r == '=' {
needsQuoting = true
break
}
}
if !needsQuoting {
return s
}
return strconv.Quote(s)
}
// writeTimeTermFormat writes on the format "01-02|15:04:05.000"
func writeTimeTermFormat(buf *bytes.Buffer, t time.Time) {
_, month, day := t.Date()
writePosIntWidth(buf, int(month), 2)
buf.WriteByte('-')
writePosIntWidth(buf, day, 2)
buf.WriteByte('|')
hour, min, sec := t.Clock()
writePosIntWidth(buf, hour, 2)
buf.WriteByte(':')
writePosIntWidth(buf, min, 2)
buf.WriteByte(':')
writePosIntWidth(buf, sec, 2)
ns := t.Nanosecond()
buf.WriteByte('.')
writePosIntWidth(buf, ns/1e6, 3)
}
// writePosIntWidth writes non-negative integer i to the buffer, padded on the left
// by zeroes to the given width. Use a width of 0 to omit padding.
// Adapted from golang.org/x/exp/slog/internal/buffer/buffer.go
func writePosIntWidth(b *bytes.Buffer, i, width int) {
// Cheap integer to fixed-width decimal ASCII.
// Copied from log/log.go.
if i < 0 {
panic("negative int")
}
// Assemble decimal in reverse order.
var bb [20]byte
bp := len(bb) - 1
for i >= 10 || width > 1 {
width--
q := i / 10
bb[bp] = byte('0' + i - q*10)
bp--
i = q
}
// i < 10
bb[bp] = byte('0' + i)
b.Write(bb[bp:])
}