// LogError logs the error to the owner of the context.
//
// If this context was created with ContextWithErrorLog, then this method
// passes the error to context creator over an unbuffered channel.
//
// If this context was created by other means, this method is a no-op.
func LogError(ctx context.Context, err error) {
v := ctx.Value(errLogKey)
errs, ok := v.(privateChanType)
if !ok {
return
}
errs <- err
}
func MetadataFromContext(ctx context.Context) (Metadata, error) {
value := ctx.Value(metadataKey)
if value != nil {
metadata, ok := value.(Metadata)
if ok {
return metadata, nil
}
}
return nil, errors.New("context contains no metadata")
}