| // Copyright 2022 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package slog_test |
| |
| import ( |
| "os" |
| |
| "golang.org/x/exp/slog" |
| ) |
| |
| // A token is a secret value that grants permissions. |
| type Token string |
| |
| // LogValue implements slog.LogValuer. |
| // It avoids revealing the token. |
| func (Token) LogValue() slog.Value { |
| return slog.StringValue("REDACTED_TOKEN") |
| } |
| |
| // This example demonstrates a Value that replaces itself |
| // with an alternative representation to avoid revealing secrets. |
| func ExampleLogValuer_secret() { |
| t := Token("shhhh!") |
| // Remove the time attribute to make Output deterministic. |
| removeTime := func(groups []string, a slog.Attr) slog.Attr { |
| if a.Key == slog.TimeKey && len(groups) == 0 { |
| a.Key = "" |
| } |
| return a |
| } |
| logger := slog.New(slog.HandlerOptions{ReplaceAttr: removeTime}.NewTextHandler(os.Stdout)) |
| logger.Info("permission granted", "user", "Perry", "token", t) |
| |
| // Output: |
| // level=INFO msg="permission granted" user=Perry token=REDACTED_TOKEN |
| } |