khenaidoo | ac63710 | 2019-01-14 15:44:34 -0500 | [diff] [blame] | 1 | // Copyright (c) 2016 Uber Technologies, Inc. |
| 2 | // |
| 3 | // Permission is hereby granted, free of charge, to any person obtaining a copy |
| 4 | // of this software and associated documentation files (the "Software"), to deal |
| 5 | // in the Software without restriction, including without limitation the rights |
| 6 | // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 7 | // copies of the Software, and to permit persons to whom the Software is |
| 8 | // furnished to do so, subject to the following conditions: |
| 9 | // |
| 10 | // The above copyright notice and this permission notice shall be included in |
| 11 | // all copies or substantial portions of the Software. |
| 12 | // |
| 13 | // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 14 | // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 15 | // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 16 | // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 17 | // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 18 | // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 19 | // THE SOFTWARE. |
| 20 | |
| 21 | package zapcore |
| 22 | |
| 23 | import ( |
| 24 | "bytes" |
| 25 | "errors" |
| 26 | "fmt" |
| 27 | ) |
| 28 | |
| 29 | var errUnmarshalNilLevel = errors.New("can't unmarshal a nil *Level") |
| 30 | |
| 31 | // A Level is a logging priority. Higher levels are more important. |
| 32 | type Level int8 |
| 33 | |
| 34 | const ( |
| 35 | // DebugLevel logs are typically voluminous, and are usually disabled in |
| 36 | // production. |
| 37 | DebugLevel Level = iota - 1 |
| 38 | // InfoLevel is the default logging priority. |
| 39 | InfoLevel |
| 40 | // WarnLevel logs are more important than Info, but don't need individual |
| 41 | // human review. |
| 42 | WarnLevel |
| 43 | // ErrorLevel logs are high-priority. If an application is running smoothly, |
| 44 | // it shouldn't generate any error-level logs. |
| 45 | ErrorLevel |
| 46 | // DPanicLevel logs are particularly important errors. In development the |
| 47 | // logger panics after writing the message. |
| 48 | DPanicLevel |
| 49 | // PanicLevel logs a message, then panics. |
| 50 | PanicLevel |
| 51 | // FatalLevel logs a message, then calls os.Exit(1). |
| 52 | FatalLevel |
| 53 | |
| 54 | _minLevel = DebugLevel |
| 55 | _maxLevel = FatalLevel |
| 56 | ) |
| 57 | |
| 58 | // String returns a lower-case ASCII representation of the log level. |
| 59 | func (l Level) String() string { |
| 60 | switch l { |
| 61 | case DebugLevel: |
| 62 | return "debug" |
| 63 | case InfoLevel: |
| 64 | return "info" |
| 65 | case WarnLevel: |
| 66 | return "warn" |
| 67 | case ErrorLevel: |
| 68 | return "error" |
| 69 | case DPanicLevel: |
| 70 | return "dpanic" |
| 71 | case PanicLevel: |
| 72 | return "panic" |
| 73 | case FatalLevel: |
| 74 | return "fatal" |
| 75 | default: |
| 76 | return fmt.Sprintf("Level(%d)", l) |
| 77 | } |
| 78 | } |
| 79 | |
| 80 | // CapitalString returns an all-caps ASCII representation of the log level. |
| 81 | func (l Level) CapitalString() string { |
| 82 | // Printing levels in all-caps is common enough that we should export this |
| 83 | // functionality. |
| 84 | switch l { |
| 85 | case DebugLevel: |
| 86 | return "DEBUG" |
| 87 | case InfoLevel: |
| 88 | return "INFO" |
| 89 | case WarnLevel: |
| 90 | return "WARN" |
| 91 | case ErrorLevel: |
| 92 | return "ERROR" |
| 93 | case DPanicLevel: |
| 94 | return "DPANIC" |
| 95 | case PanicLevel: |
| 96 | return "PANIC" |
| 97 | case FatalLevel: |
| 98 | return "FATAL" |
| 99 | default: |
| 100 | return fmt.Sprintf("LEVEL(%d)", l) |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | // MarshalText marshals the Level to text. Note that the text representation |
| 105 | // drops the -Level suffix (see example). |
| 106 | func (l Level) MarshalText() ([]byte, error) { |
| 107 | return []byte(l.String()), nil |
| 108 | } |
| 109 | |
| 110 | // UnmarshalText unmarshals text to a level. Like MarshalText, UnmarshalText |
| 111 | // expects the text representation of a Level to drop the -Level suffix (see |
| 112 | // example). |
| 113 | // |
| 114 | // In particular, this makes it easy to configure logging levels using YAML, |
| 115 | // TOML, or JSON files. |
| 116 | func (l *Level) UnmarshalText(text []byte) error { |
| 117 | if l == nil { |
| 118 | return errUnmarshalNilLevel |
| 119 | } |
| 120 | if !l.unmarshalText(text) && !l.unmarshalText(bytes.ToLower(text)) { |
| 121 | return fmt.Errorf("unrecognized level: %q", text) |
| 122 | } |
| 123 | return nil |
| 124 | } |
| 125 | |
| 126 | func (l *Level) unmarshalText(text []byte) bool { |
| 127 | switch string(text) { |
| 128 | case "debug", "DEBUG": |
| 129 | *l = DebugLevel |
| 130 | case "info", "INFO", "": // make the zero value useful |
| 131 | *l = InfoLevel |
| 132 | case "warn", "WARN": |
| 133 | *l = WarnLevel |
| 134 | case "error", "ERROR": |
| 135 | *l = ErrorLevel |
| 136 | case "dpanic", "DPANIC": |
| 137 | *l = DPanicLevel |
| 138 | case "panic", "PANIC": |
| 139 | *l = PanicLevel |
| 140 | case "fatal", "FATAL": |
| 141 | *l = FatalLevel |
| 142 | default: |
| 143 | return false |
| 144 | } |
| 145 | return true |
| 146 | } |
| 147 | |
| 148 | // Set sets the level for the flag.Value interface. |
| 149 | func (l *Level) Set(s string) error { |
| 150 | return l.UnmarshalText([]byte(s)) |
| 151 | } |
| 152 | |
| 153 | // Get gets the level for the flag.Getter interface. |
| 154 | func (l *Level) Get() interface{} { |
| 155 | return *l |
| 156 | } |
| 157 | |
| 158 | // Enabled returns true if the given level is at or above this level. |
| 159 | func (l Level) Enabled(lvl Level) bool { |
| 160 | return lvl >= l |
| 161 | } |
| 162 | |
| 163 | // LevelEnabler decides whether a given logging level is enabled when logging a |
| 164 | // message. |
| 165 | // |
| 166 | // Enablers are intended to be used to implement deterministic filters; |
| 167 | // concerns like sampling are better implemented as a Core. |
| 168 | // |
| 169 | // Each concrete Level value implements a static LevelEnabler which returns |
| 170 | // true for itself and all higher logging levels. For example WarnLevel.Enabled() |
| 171 | // will return true for WarnLevel, ErrorLevel, DPanicLevel, PanicLevel, and |
| 172 | // FatalLevel, but return false for InfoLevel and DebugLevel. |
| 173 | type LevelEnabler interface { |
| 174 | Enabled(Level) bool |
| 175 | } |