logrus/text_formatter.go

274 lines
6.8 KiB
Go

package logrus
import (
"bytes"
"fmt"
"os"
"runtime"
"sort"
"strings"
"sync"
"time"
)
const (
nocolor = 0
red = 31
green = 32
yellow = 33
blue = 36
gray = 37
)
var (
baseTimestamp time.Time
emptyFieldMap FieldMap
)
func init() {
baseTimestamp = time.Now()
}
// TextFormatter formats logs into text
type TextFormatter struct {
// Set to true to bypass checking for a TTY before outputting colors.
ForceColors bool
// Force disabling colors.
DisableColors bool
// Override coloring based on CLICOLOR and CLICOLOR_FORCE. - https://bixense.com/clicolors/
EnvironmentOverrideColors bool
// Disable timestamp logging. useful when output is redirected to logging
// system that already adds timestamps.
DisableTimestamp bool
// Enable logging the full timestamp when a TTY is attached instead of just
// the time passed since beginning of execution.
FullTimestamp bool
// TimestampFormat to use for display when a full timestamp is printed
TimestampFormat string
// The fields are sorted by default for a consistent output. For applications
// that log extremely frequently and don't use the JSON formatter this may not
// be desired.
DisableSorting bool
// The keys sorting function, when uninitialized it uses sort.Strings.
SortingFunc func([]string)
// Disables the truncation of the level text to 4 characters.
DisableLevelTruncation bool
// QuoteEmptyFields will wrap empty fields in quotes if true
QuoteEmptyFields bool
// Whether the logger's out is to a terminal
isTerminal bool
// FieldMap allows users to customize the names of keys for default fields.
// As an example:
// formatter := &TextFormatter{
// FieldMap: FieldMap{
// FieldKeyTime: "@timestamp",
// FieldKeyLevel: "@level",
// FieldKeyMsg: "@message"}}
FieldMap FieldMap
terminalInitOnce sync.Once
}
func (f *TextFormatter) init(entry *Entry) {
if entry.Logger != nil {
f.isTerminal = checkIfTerminal(entry.Logger.Out)
if f.isTerminal {
initTerminal(entry.Logger.Out)
}
}
}
func (f *TextFormatter) isColored() bool {
isColored := f.ForceColors || (f.isTerminal && (runtime.GOOS != "windows"))
if f.EnvironmentOverrideColors {
if force, ok := os.LookupEnv("CLICOLOR_FORCE"); ok && force != "0" {
isColored = true
} else if ok && force == "0" {
isColored = false
} else if os.Getenv("CLICOLOR") == "0" {
isColored = false
}
}
return isColored && !f.DisableColors
}
// Format renders a single log entry
func (f *TextFormatter) Format(entry *Entry) ([]byte, error) {
data := make(Fields)
for k, v := range entry.Data {
data[k] = v
}
prefixFieldClashes(data, f.FieldMap, entry.HasCaller())
keys := make([]string, 0, len(data))
for k := range data {
keys = append(keys, k)
}
fixedKeys := make([]string, 0, 4+len(data))
if !f.DisableTimestamp {
fixedKeys = append(fixedKeys, f.FieldMap.resolve(FieldKeyTime))
}
fixedKeys = append(fixedKeys, f.FieldMap.resolve(FieldKeyLevel))
if entry.Message != "" {
fixedKeys = append(fixedKeys, f.FieldMap.resolve(FieldKeyMsg))
}
if entry.err != "" {
fixedKeys = append(fixedKeys, f.FieldMap.resolve(FieldKeyLogrusError))
}
if entry.HasCaller() {
fixedKeys = append(fixedKeys,
f.FieldMap.resolve(FieldKeyFunc), f.FieldMap.resolve(FieldKeyFile))
}
if !f.DisableSorting {
if f.SortingFunc == nil {
sort.Strings(keys)
fixedKeys = append(fixedKeys, keys...)
} else {
if !f.isColored() {
fixedKeys = append(fixedKeys, keys...)
f.SortingFunc(fixedKeys)
} else {
f.SortingFunc(keys)
}
}
} else {
fixedKeys = append(fixedKeys, keys...)
}
var b *bytes.Buffer
if entry.Buffer != nil {
b = entry.Buffer
} else {
b = &bytes.Buffer{}
}
f.terminalInitOnce.Do(func() { f.init(entry) })
timestampFormat := f.TimestampFormat
if timestampFormat == "" {
timestampFormat = defaultTimestampFormat
}
if f.isColored() {
f.printColored(b, entry, keys, data, timestampFormat)
} else {
for _, key := range fixedKeys {
var value interface{}
switch {
case key == f.FieldMap.resolve(FieldKeyTime):
value = entry.Time.Format(timestampFormat)
case key == f.FieldMap.resolve(FieldKeyLevel):
value = entry.Level.String()
case key == f.FieldMap.resolve(FieldKeyMsg):
value = entry.Message
case key == f.FieldMap.resolve(FieldKeyLogrusError):
value = entry.err
case key == f.FieldMap.resolve(FieldKeyFunc) && entry.HasCaller():
value = entry.Caller.Function
case key == f.FieldMap.resolve(FieldKeyFile) && entry.HasCaller():
value = fmt.Sprintf("%s:%d", entry.Caller.File, entry.Caller.Line)
default:
value = data[key]
}
f.appendKeyValue(b, key, value)
}
}
b.WriteByte('\n')
return b.Bytes(), nil
}
func (f *TextFormatter) printColored(b *bytes.Buffer, entry *Entry, keys []string, data Fields, timestampFormat string) {
var levelColor int
switch entry.Level {
case DebugLevel, TraceLevel:
levelColor = gray
case WarnLevel:
levelColor = yellow
case ErrorLevel, FatalLevel, PanicLevel:
levelColor = red
default:
levelColor = blue
}
levelText := strings.ToUpper(entry.Level.String())
if !f.DisableLevelTruncation {
levelText = levelText[0:4]
}
// Remove a single newline if it already exists in the message to keep
// the behavior of logrus text_formatter the same as the stdlib log package
entry.Message = strings.TrimSuffix(entry.Message, "\n")
caller := ""
if entry.HasCaller() {
caller = fmt.Sprintf("%s:%d %s()",
entry.Caller.File, entry.Caller.Line, entry.Caller.Function)
}
if f.DisableTimestamp {
fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m%s %-44s ", levelColor, levelText, caller, entry.Message)
} else if !f.FullTimestamp {
fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%04d]%s %-44s ", levelColor, levelText, int(entry.Time.Sub(baseTimestamp)/time.Second), caller, entry.Message)
} else {
fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%s]%s %-44s ", levelColor, levelText, entry.Time.Format(timestampFormat), caller, entry.Message)
}
for _, k := range keys {
v := data[k]
fmt.Fprintf(b, " \x1b[%dm%s\x1b[0m=", levelColor, k)
f.appendValue(b, v)
}
}
func (f *TextFormatter) needsQuoting(text string) bool {
if f.QuoteEmptyFields && len(text) == 0 {
return true
}
for _, ch := range text {
if !((ch >= 'a' && ch <= 'z') ||
(ch >= 'A' && ch <= 'Z') ||
(ch >= '0' && ch <= '9') ||
ch == '-' || ch == '.' || ch == '_' || ch == '/' || ch == '@' || ch == '^' || ch == '+') {
return true
}
}
return false
}
func (f *TextFormatter) appendKeyValue(b *bytes.Buffer, key string, value interface{}) {
if b.Len() > 0 {
b.WriteByte(' ')
}
b.WriteString(key)
b.WriteByte('=')
f.appendValue(b, value)
}
func (f *TextFormatter) appendValue(b *bytes.Buffer, value interface{}) {
stringVal, ok := value.(string)
if !ok {
stringVal = fmt.Sprint(value)
}
if !f.needsQuoting(stringVal) {
b.WriteString(stringVal)
} else {
b.WriteString(fmt.Sprintf("%q", stringVal))
}
}