1// Copyright 2023 The Go Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style 3// license that can be found in the LICENSE file. 4 5package slog_test 6 7import ( 8 "log" 9 "log/slog" 10 "log/slog/internal/slogtest" 11 "os" 12) 13 14// This example shows how to use slog.SetLogLoggerLevel to change the minimal level 15// of the internal default handler for slog package before calling slog.SetDefault. 16func ExampleSetLogLoggerLevel_log() { 17 defer log.SetFlags(log.Flags()) // revert changes after the example 18 log.SetFlags(0) 19 defer log.SetOutput(log.Writer()) // revert changes after the example 20 log.SetOutput(os.Stdout) 21 22 // Default logging level is slog.LevelInfo. 23 log.Print("log debug") // log debug 24 slog.Debug("debug") // no output 25 slog.Info("info") // INFO info 26 27 // Set the default logging level to slog.LevelDebug. 28 currentLogLevel := slog.SetLogLoggerLevel(slog.LevelDebug) 29 defer slog.SetLogLoggerLevel(currentLogLevel) // revert changes after the example 30 31 log.Print("log debug") // log debug 32 slog.Debug("debug") // DEBUG debug 33 slog.Info("info") // INFO info 34 35 // Output: 36 // log debug 37 // INFO info 38 // log debug 39 // DEBUG debug 40 // INFO info 41} 42 43// This example shows how to use slog.SetLogLoggerLevel to change the minimal level 44// of the internal writer that uses the custom handler for log package after 45// calling slog.SetDefault. 46func ExampleSetLogLoggerLevel_slog() { 47 // Set the default logging level to slog.LevelError. 48 currentLogLevel := slog.SetLogLoggerLevel(slog.LevelError) 49 defer slog.SetLogLoggerLevel(currentLogLevel) // revert changes after the example 50 51 defer slog.SetDefault(slog.Default()) // revert changes after the example 52 slog.SetDefault(slog.New(slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{ReplaceAttr: slogtest.RemoveTime}))) 53 54 log.Print("error") // level=ERROR msg=error 55 56 // Output: 57 // level=ERROR msg=error 58} 59