+ unless ($self->{cache}) {
+ tie my %cache, 'Tie::Hash::Expire', {expire_seconds => $self->{cache_max_age}};
+ $self->{cache} = \%cache;
+ }
+ my $cachekey = sha256 "$username:$passphrase";
+ return $self->{cache}{$cachekey} if exists $self->{cache}{$cachekey}; # uncoverable branch true