Files
log/format.go

291 lines
7.0 KiB
Go

// FILE: format.go
package log
import (
"fmt"
"strconv"
"strings"
"time"
)
// serializer manages the buffered writing of log entries.
type serializer struct {
buf []byte
timestampFormat string
}
// newSerializer creates a serializer instance.
func newSerializer() *serializer {
return &serializer{
buf: make([]byte, 0, 4096), // Initial reasonable capacity
timestampFormat: time.RFC3339Nano, // Default until configured
}
}
// reset clears the serializer buffer for reuse.
func (s *serializer) reset() {
s.buf = s.buf[:0]
}
// serialize converts log entries to the configured format, JSON or (default) text.
func (s *serializer) serialize(format string, flags int64, timestamp time.Time, level int64, trace string, args []any) []byte {
s.reset()
if format == "json" {
return s.serializeJSON(flags, timestamp, level, trace, args)
}
return s.serializeText(flags, timestamp, level, trace, args)
}
// serializeJSON formats log entries as JSON (time, level, trace, fields).
func (s *serializer) serializeJSON(flags int64, timestamp time.Time, level int64, trace string, args []any) []byte {
s.buf = append(s.buf, '{')
needsComma := false
if flags&FlagShowTimestamp != 0 {
s.buf = append(s.buf, `"time":"`...)
s.buf = timestamp.AppendFormat(s.buf, s.timestampFormat)
s.buf = append(s.buf, '"')
needsComma = true
}
if flags&FlagShowLevel != 0 {
if needsComma {
s.buf = append(s.buf, ',')
}
s.buf = append(s.buf, `"level":"`...)
s.buf = append(s.buf, levelToString(level)...)
s.buf = append(s.buf, '"')
needsComma = true
}
if trace != "" {
if needsComma {
s.buf = append(s.buf, ',')
}
s.buf = append(s.buf, `"trace":"`...)
s.writeString(trace) // Ensure trace string is escaped
s.buf = append(s.buf, '"')
needsComma = true
}
if len(args) > 0 {
if needsComma {
s.buf = append(s.buf, ',')
}
s.buf = append(s.buf, `"fields":[`...)
for i, arg := range args {
if i > 0 {
s.buf = append(s.buf, ',')
}
s.writeJSONValue(arg)
}
s.buf = append(s.buf, ']')
}
s.buf = append(s.buf, '}', '\n')
return s.buf
}
// serializeText formats log entries as plain text (time, level, trace, fields).
func (s *serializer) serializeText(flags int64, timestamp time.Time, level int64, trace string, args []any) []byte {
needsSpace := false
if flags&FlagShowTimestamp != 0 {
s.buf = timestamp.AppendFormat(s.buf, s.timestampFormat)
needsSpace = true
}
if flags&FlagShowLevel != 0 {
if needsSpace {
s.buf = append(s.buf, ' ')
}
s.buf = append(s.buf, levelToString(level)...)
needsSpace = true
}
if trace != "" {
if needsSpace {
s.buf = append(s.buf, ' ')
}
s.buf = append(s.buf, trace...)
needsSpace = true
}
for _, arg := range args {
if needsSpace {
s.buf = append(s.buf, ' ')
}
s.writeTextValue(arg)
needsSpace = true
}
s.buf = append(s.buf, '\n')
return s.buf
}
// writeTextValue converts any value to its text representation.
func (s *serializer) writeTextValue(v any) {
switch val := v.(type) {
case string:
if len(val) == 0 || strings.ContainsRune(val, ' ') {
s.buf = append(s.buf, '"')
s.writeString(val)
s.buf = append(s.buf, '"')
} else {
s.buf = append(s.buf, val...)
}
case int:
s.buf = strconv.AppendInt(s.buf, int64(val), 10)
case int64:
s.buf = strconv.AppendInt(s.buf, val, 10)
case uint:
s.buf = strconv.AppendUint(s.buf, uint64(val), 10)
case uint64:
s.buf = strconv.AppendUint(s.buf, val, 10)
case float32:
s.buf = strconv.AppendFloat(s.buf, float64(val), 'f', -1, 32)
case float64:
s.buf = strconv.AppendFloat(s.buf, val, 'f', -1, 64)
case bool:
s.buf = strconv.AppendBool(s.buf, val)
case nil:
s.buf = append(s.buf, "null"...)
case time.Time:
s.buf = val.AppendFormat(s.buf, s.timestampFormat)
case error:
str := val.Error()
if len(str) == 0 || strings.ContainsRune(str, ' ') {
s.buf = append(s.buf, '"')
s.writeString(str)
s.buf = append(s.buf, '"')
} else {
s.buf = append(s.buf, str...)
}
case fmt.Stringer:
str := val.String()
if len(str) == 0 || strings.ContainsRune(str, ' ') {
s.buf = append(s.buf, '"')
s.writeString(str)
s.buf = append(s.buf, '"')
} else {
s.buf = append(s.buf, str...)
}
default:
str := fmt.Sprintf("%+v", val)
if len(str) == 0 || strings.ContainsRune(str, ' ') {
s.buf = append(s.buf, '"')
s.writeString(str)
s.buf = append(s.buf, '"')
} else {
s.buf = append(s.buf, str...)
}
}
}
// writeJSONValue converts any value to its JSON representation.
func (s *serializer) writeJSONValue(v any) {
switch val := v.(type) {
case string:
s.buf = append(s.buf, '"')
s.writeString(val)
s.buf = append(s.buf, '"')
case int:
s.buf = strconv.AppendInt(s.buf, int64(val), 10)
case int64:
s.buf = strconv.AppendInt(s.buf, val, 10)
case uint:
s.buf = strconv.AppendUint(s.buf, uint64(val), 10)
case uint64:
s.buf = strconv.AppendUint(s.buf, val, 10)
case float32:
s.buf = strconv.AppendFloat(s.buf, float64(val), 'f', -1, 32)
case float64:
s.buf = strconv.AppendFloat(s.buf, val, 'f', -1, 64)
case bool:
s.buf = strconv.AppendBool(s.buf, val)
case nil:
s.buf = append(s.buf, "null"...)
case time.Time:
s.buf = append(s.buf, '"')
s.buf = val.AppendFormat(s.buf, s.timestampFormat)
s.buf = append(s.buf, '"')
case error:
s.buf = append(s.buf, '"')
s.writeString(val.Error())
s.buf = append(s.buf, '"')
case fmt.Stringer:
s.buf = append(s.buf, '"')
s.writeString(val.String())
s.buf = append(s.buf, '"')
default:
s.buf = append(s.buf, '"')
s.writeString(fmt.Sprintf("%+v", val))
s.buf = append(s.buf, '"')
}
}
// Update the levelToString function to include the new heartbeat levels
func levelToString(level int64) string {
switch level {
case LevelDebug:
return "DEBUG"
case LevelInfo:
return "INFO"
case LevelWarn:
return "WARN"
case LevelError:
return "ERROR"
case LevelProc:
return "PROC"
case LevelDisk:
return "DISK"
case LevelSys:
return "SYS"
default:
return fmt.Sprintf("LEVEL(%d)", level)
}
}
// writeString appends a string to the buffer, escaping JSON special characters.
func (s *serializer) writeString(str string) {
lenStr := len(str)
for i := 0; i < lenStr; {
if c := str[i]; c < ' ' || c == '"' || c == '\\' {
switch c {
case '\\', '"':
s.buf = append(s.buf, '\\', c)
case '\n':
s.buf = append(s.buf, '\\', 'n')
case '\r':
s.buf = append(s.buf, '\\', 'r')
case '\t':
s.buf = append(s.buf, '\\', 't')
case '\b':
s.buf = append(s.buf, '\\', 'b')
case '\f':
s.buf = append(s.buf, '\\', 'f')
default:
s.buf = append(s.buf, `\u00`...)
s.buf = append(s.buf, hexChars[c>>4], hexChars[c&0xF])
}
i++
} else {
start := i
for i < lenStr && str[i] >= ' ' && str[i] != '"' && str[i] != '\\' {
i++
}
s.buf = append(s.buf, str[start:i]...)
}
}
}
// Update cached format
func (s *serializer) setTimestampFormat(format string) {
if format == "" {
format = time.RFC3339Nano
}
s.timestampFormat = format
}
const hexChars = "0123456789abcdef"