David K. Bainbridge | 215e024 | 2017-09-05 23:18:24 -0700 | [diff] [blame] | 1 | package logrus |
| 2 | |
| 3 | import ( |
| 4 | "bytes" |
| 5 | "fmt" |
| 6 | "sort" |
| 7 | "strings" |
| 8 | "sync" |
| 9 | "time" |
| 10 | ) |
| 11 | |
| 12 | const ( |
| 13 | nocolor = 0 |
| 14 | red = 31 |
| 15 | green = 32 |
| 16 | yellow = 33 |
| 17 | blue = 34 |
| 18 | gray = 37 |
| 19 | ) |
| 20 | |
| 21 | var ( |
| 22 | baseTimestamp time.Time |
| 23 | ) |
| 24 | |
| 25 | func init() { |
| 26 | baseTimestamp = time.Now() |
| 27 | } |
| 28 | |
| 29 | type TextFormatter struct { |
| 30 | // Set to true to bypass checking for a TTY before outputting colors. |
| 31 | ForceColors bool |
| 32 | |
| 33 | // Force disabling colors. |
| 34 | DisableColors bool |
| 35 | |
| 36 | // Disable timestamp logging. useful when output is redirected to logging |
| 37 | // system that already adds timestamps. |
| 38 | DisableTimestamp bool |
| 39 | |
| 40 | // Enable logging the full timestamp when a TTY is attached instead of just |
| 41 | // the time passed since beginning of execution. |
| 42 | FullTimestamp bool |
| 43 | |
| 44 | // TimestampFormat to use for display when a full timestamp is printed |
| 45 | TimestampFormat string |
| 46 | |
| 47 | // The fields are sorted by default for a consistent output. For applications |
| 48 | // that log extremely frequently and don't use the JSON formatter this may not |
| 49 | // be desired. |
| 50 | DisableSorting bool |
| 51 | |
| 52 | // QuoteEmptyFields will wrap empty fields in quotes if true |
| 53 | QuoteEmptyFields bool |
| 54 | |
| 55 | // QuoteCharacter can be set to the override the default quoting character " |
| 56 | // with something else. For example: ', or `. |
| 57 | QuoteCharacter string |
| 58 | |
| 59 | // Whether the logger's out is to a terminal |
| 60 | isTerminal bool |
| 61 | |
| 62 | sync.Once |
| 63 | } |
| 64 | |
| 65 | func (f *TextFormatter) init(entry *Entry) { |
| 66 | if len(f.QuoteCharacter) == 0 { |
| 67 | f.QuoteCharacter = "\"" |
| 68 | } |
| 69 | if entry.Logger != nil { |
| 70 | f.isTerminal = IsTerminal(entry.Logger.Out) |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | func (f *TextFormatter) Format(entry *Entry) ([]byte, error) { |
| 75 | var b *bytes.Buffer |
| 76 | keys := make([]string, 0, len(entry.Data)) |
| 77 | for k := range entry.Data { |
| 78 | keys = append(keys, k) |
| 79 | } |
| 80 | |
| 81 | if !f.DisableSorting { |
| 82 | sort.Strings(keys) |
| 83 | } |
| 84 | if entry.Buffer != nil { |
| 85 | b = entry.Buffer |
| 86 | } else { |
| 87 | b = &bytes.Buffer{} |
| 88 | } |
| 89 | |
| 90 | prefixFieldClashes(entry.Data) |
| 91 | |
| 92 | f.Do(func() { f.init(entry) }) |
| 93 | |
| 94 | isColored := (f.ForceColors || f.isTerminal) && !f.DisableColors |
| 95 | |
| 96 | timestampFormat := f.TimestampFormat |
| 97 | if timestampFormat == "" { |
| 98 | timestampFormat = DefaultTimestampFormat |
| 99 | } |
| 100 | if isColored { |
| 101 | f.printColored(b, entry, keys, timestampFormat) |
| 102 | } else { |
| 103 | if !f.DisableTimestamp { |
| 104 | f.appendKeyValue(b, "time", entry.Time.Format(timestampFormat)) |
| 105 | } |
| 106 | f.appendKeyValue(b, "level", entry.Level.String()) |
| 107 | if entry.Message != "" { |
| 108 | f.appendKeyValue(b, "msg", entry.Message) |
| 109 | } |
| 110 | for _, key := range keys { |
| 111 | f.appendKeyValue(b, key, entry.Data[key]) |
| 112 | } |
| 113 | } |
| 114 | |
| 115 | b.WriteByte('\n') |
| 116 | return b.Bytes(), nil |
| 117 | } |
| 118 | |
| 119 | func (f *TextFormatter) printColored(b *bytes.Buffer, entry *Entry, keys []string, timestampFormat string) { |
| 120 | var levelColor int |
| 121 | switch entry.Level { |
| 122 | case DebugLevel: |
| 123 | levelColor = gray |
| 124 | case WarnLevel: |
| 125 | levelColor = yellow |
| 126 | case ErrorLevel, FatalLevel, PanicLevel: |
| 127 | levelColor = red |
| 128 | default: |
| 129 | levelColor = blue |
| 130 | } |
| 131 | |
| 132 | levelText := strings.ToUpper(entry.Level.String())[0:4] |
| 133 | |
| 134 | if f.DisableTimestamp { |
| 135 | fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m %-44s ", levelColor, levelText, entry.Message) |
| 136 | } else if !f.FullTimestamp { |
| 137 | fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%04d] %-44s ", levelColor, levelText, int(entry.Time.Sub(baseTimestamp)/time.Second), entry.Message) |
| 138 | } else { |
| 139 | fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%s] %-44s ", levelColor, levelText, entry.Time.Format(timestampFormat), entry.Message) |
| 140 | } |
| 141 | for _, k := range keys { |
| 142 | v := entry.Data[k] |
| 143 | fmt.Fprintf(b, " \x1b[%dm%s\x1b[0m=", levelColor, k) |
| 144 | f.appendValue(b, v) |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | func (f *TextFormatter) needsQuoting(text string) bool { |
| 149 | if f.QuoteEmptyFields && len(text) == 0 { |
| 150 | return true |
| 151 | } |
| 152 | for _, ch := range text { |
| 153 | if !((ch >= 'a' && ch <= 'z') || |
| 154 | (ch >= 'A' && ch <= 'Z') || |
| 155 | (ch >= '0' && ch <= '9') || |
| 156 | ch == '-' || ch == '.') { |
| 157 | return true |
| 158 | } |
| 159 | } |
| 160 | return false |
| 161 | } |
| 162 | |
| 163 | func (f *TextFormatter) appendKeyValue(b *bytes.Buffer, key string, value interface{}) { |
| 164 | |
| 165 | b.WriteString(key) |
| 166 | b.WriteByte('=') |
| 167 | f.appendValue(b, value) |
| 168 | b.WriteByte(' ') |
| 169 | } |
| 170 | |
| 171 | func (f *TextFormatter) appendValue(b *bytes.Buffer, value interface{}) { |
| 172 | switch value := value.(type) { |
| 173 | case string: |
| 174 | if !f.needsQuoting(value) { |
| 175 | b.WriteString(value) |
| 176 | } else { |
| 177 | b.WriteString(f.quoteString(value)) |
| 178 | } |
| 179 | case error: |
| 180 | errmsg := value.Error() |
| 181 | if !f.needsQuoting(errmsg) { |
| 182 | b.WriteString(errmsg) |
| 183 | } else { |
| 184 | b.WriteString(f.quoteString(errmsg)) |
| 185 | } |
| 186 | default: |
| 187 | fmt.Fprint(b, value) |
| 188 | } |
| 189 | } |
| 190 | |
| 191 | func (f *TextFormatter) quoteString(v string) string { |
| 192 | escapedQuote := fmt.Sprintf("\\%s", f.QuoteCharacter) |
| 193 | escapedValue := strings.Replace(v, f.QuoteCharacter, escapedQuote, -1) |
| 194 | |
| 195 | return fmt.Sprintf("%s%v%s", f.QuoteCharacter, escapedValue, f.QuoteCharacter) |
| 196 | } |