logger.go

type contextKey struct{}

// FromContext returns the current zap logger from the given context, or
// the default global logger (by calling zap.L()) otherwise.
func FromContext(ctx context.Context) *zap.Logger {
    if v, ok := ctx.Value(contextKey{}).(*zap.Logger); ok {
        return v
    }
    return zap.L()
}

// WithContext returns a context.Context with a Value containing the given
// zap logger.
func WithContext(ctx context.Context, l *zap.Logger) context.Context {
    return context.WithValue(ctx, contextKey{}, l)
}

// Check calls zap.Check on the logger for ctx.
func Check(ctx context.Context, lvl zapcore.Level, msg string) *zapcore.CheckedEntry {
    return FromContext(ctx).Check(lvl, msg)
}

// Debug calls zap.Debug on the logger for ctx.
func Debug(ctx context.Context, msg string, fields ...zapcore.Field) {
    FromContext(ctx).Debug(msg, fields...)
}

// Error calls zap.Error on the logger for ctx.
func Error(ctx context.Context, msg string, fields ...zapcore.Field) {
    FromContext(ctx).Error(msg, fields...)
}

// Info calls zap.Info on the logger for ctx.
func Info(ctx context.Context, msg string, fields ...zapcore.Field) {
    FromContext(ctx).Info(msg, fields...)
}

// Named calls zap.Named on the logger for ctx.
func Named(ctx context.Context, s string) context.Context {
    return WithContext(ctx, FromContext(ctx).Named(s))
}

// Sync calls zap.Sync on the logger for ctx.
func Sync(ctx context.Context) error { return FromContext(ctx).Sync() }

// Warn calls zap.Warn on the logger for ctx.
func Warn(ctx context.Context, msg string, fields ...zapcore.Field) {
    FromContext(ctx).Warn(msg, fields...)
}

// With calls zap.With on the logger for ctx.
func With(ctx context.Context, fields ...zapcore.Field) context.Context {
    return WithContext(ctx, FromContext(ctx).With(fields...))
}

// WithOptions calls zap.WithOptions on the logger for ctx.
func WithOptions(ctx context.Context, opts ...zap.Option) context.Context {
    return WithContext(ctx, FromContext(ctx).WithOptions(opts...))
}