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 21package zap 22 23import "go.uber.org/zap/zapcore" 24 25// An Option configures a Logger. 26type Option interface { 27 apply(*Logger) 28} 29 30// optionFunc wraps a func so it satisfies the Option interface. 31type optionFunc func(*Logger) 32 33func (f optionFunc) apply(log *Logger) { 34 f(log) 35} 36 37// WrapCore wraps or replaces the Logger's underlying zapcore.Core. 38func WrapCore(f func(zapcore.Core) zapcore.Core) Option { 39 return optionFunc(func(log *Logger) { 40 log.core = f(log.core) 41 }) 42} 43 44// Hooks registers functions which will be called each time the Logger writes 45// out an Entry. Repeated use of Hooks is additive. 46// 47// Hooks are useful for simple side effects, like capturing metrics for the 48// number of emitted logs. More complex side effects, including anything that 49// requires access to the Entry's structured fields, should be implemented as 50// a zapcore.Core instead. See zapcore.RegisterHooks for details. 51func Hooks(hooks ...func(zapcore.Entry) error) Option { 52 return optionFunc(func(log *Logger) { 53 log.core = zapcore.RegisterHooks(log.core, hooks...) 54 }) 55} 56 57// Fields adds fields to the Logger. 58func Fields(fs ...Field) Option { 59 return optionFunc(func(log *Logger) { 60 log.core = log.core.With(fs) 61 }) 62} 63 64// ErrorOutput sets the destination for errors generated by the Logger. Note 65// that this option only affects internal errors; for sample code that sends 66// error-level logs to a different location from info- and debug-level logs, 67// see the package-level AdvancedConfiguration example. 68// 69// The supplied WriteSyncer must be safe for concurrent use. The Open and 70// zapcore.Lock functions are the simplest ways to protect files with a mutex. 71func ErrorOutput(w zapcore.WriteSyncer) Option { 72 return optionFunc(func(log *Logger) { 73 log.errorOutput = w 74 }) 75} 76 77// Development puts the logger in development mode, which makes DPanic-level 78// logs panic instead of simply logging an error. 79func Development() Option { 80 return optionFunc(func(log *Logger) { 81 log.development = true 82 }) 83} 84 85// AddCaller configures the Logger to annotate each message with the filename 86// and line number of zap's caller. 87func AddCaller() Option { 88 return optionFunc(func(log *Logger) { 89 log.addCaller = true 90 }) 91} 92 93// AddCallerSkip increases the number of callers skipped by caller annotation 94// (as enabled by the AddCaller option). When building wrappers around the 95// Logger and SugaredLogger, supplying this Option prevents zap from always 96// reporting the wrapper code as the caller. 97func AddCallerSkip(skip int) Option { 98 return optionFunc(func(log *Logger) { 99 log.callerSkip += skip 100 }) 101} 102 103// AddStacktrace configures the Logger to record a stack trace for all messages at 104// or above a given level. 105func AddStacktrace(lvl zapcore.LevelEnabler) Option { 106 return optionFunc(func(log *Logger) { 107 log.addStack = lvl 108 }) 109} 110