| // 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 |
| |
| import "context" |
| |
| type contextKey struct{} |
| |
| // NewContext returns a context that contains the given Logger. |
| // Use FromContext to retrieve the Logger. |
| func NewContext(ctx context.Context, l *Logger) context.Context { |
| return context.WithValue(ctx, contextKey{}, l) |
| } |
| |
| // FromContext returns the Logger stored in ctx by NewContext, or the default |
| // Logger if there is none. |
| func FromContext(ctx context.Context) *Logger { |
| if l, ok := ctx.Value(contextKey{}).(*Logger); ok { |
| return l |
| } |
| return Default() |
| } |
| |
| // Ctx retrieves a Logger from the given context using FromContext. Then it adds |
| // the given context to the Logger using WithContext and returns the result. |
| func Ctx(ctx context.Context) *Logger { |
| return FromContext(ctx).WithContext(ctx) |
| } |