No DB settings for database

Using YARBAC with Dancer2 and Database. This has been working but abruptly stopped working yesterday. Immediately prior to it stopping working, I installed Dancer2::Serializer::JSON. Not sure that was the cause of the issue but I thought I'd mention it in case it's relevant. I used git to restore my app to a previous version which was working fine, and it continues to fail. The error I'm getting on the web page is a 500: Can't call method "quick_select" on an undefined value at /usr/local/share/perl/5.14.2/Dancer2/Plugin/Auth/YARBAC/Provider/Database.pm line 108.

The call stack is:

```
main in -e l. 0
main in -e l. 0
Plack::Handler::Apache2 in /usr/local/share/perl/5.14.2/Plack/Handler/Apache2.pm l. 126
Plack::Handler::Apache2 in /usr/local/share/perl/5.14.2/Plack/Handler/Apache2.pm l. 87
Plack::Component in /usr/local/share/perl/5.14.2/Plack/Component.pm l. 50
Plack::Middleware::Head in /usr/local/share/perl/5.14.2/Plack/Middleware/Head.pm l. 9
Plack::Component in /usr/local/share/perl/5.14.2/Plack/Component.pm l. 50
Plack::Middleware::Static in /usr/local/share/perl/5.14.2/Plack/Middleware/Static.pm l. 18
Plack::Component in /usr/local/share/perl/5.14.2/Plack/Component.pm l. 50
Plack::Middleware::FixMissingBodyInRedirect in /usr/local/share/perl/5.14.2/Plack/Middleware/FixMissingBodyInRedirect.pm l. 50
Dancer2::Core::App in /usr/local/share/perl/5.14.2/Dancer2/Core/App.pm l. 1300
Dancer2::Core::App in /usr/local/share/perl/5.14.2/Dancer2/Core/App.pm l. 1298
Dancer2::Core::App in /usr/local/share/perl/5.14.2/Dancer2/Core/App.pm l. 1379
Return::MultiLevel in /usr/local/share/perl/5.14.2/Return/MultiLevel.pm l. 97
Return::MultiLevel in /usr/local/share/perl/5.14.2/Return/MultiLevel.pm l. 61
Dancer2::Core::App in /usr/local/share/perl/5.14.2/Dancer2/Core/App.pm l. 1378
Dancer2::Core::App in /usr/local/share/perl/5.14.2/Dancer2/Core/App.pm l. 1489
Dancer2::Core::App in /usr/local/share/perl/5.14.2/Dancer2/Core/App.pm l. 1522
Dancer2::Core::Error in /usr/local/share/perl/5.14.2/Dancer2/Core/Error.pm l. 303
Method::Generate::Accessor in (eval 652) l. 18
Dancer2::Core::Error in /usr/local/share/perl/5.14.2/Dancer2/Core/Error.pm l. 290
Dancer2::Core::Error in /usr/local/share/perl/5.14.2/Dancer2/Core/Error.pm l. 111
Dancer2::Core::Error in /usr/local/share/perl/5.14.2/Dancer2/Core/Error.pm l. 160
Dancer2::Core::Error in /usr/local/share/perl/5.14.2/Dancer2/Core/Error.pm l. 386
```

Checking the Apache log, however, I find:

[Dancer2::Plugin::Auth::YARBAC::Provider::Database:31005] error @2016-06-06 08:21:31> No DB settings for sonic in /usr/local/share/perl/5.14.2/Dancer2/Core/App.pm l. 836

That error actually appears to come from Dancer/Plugin/Database/Core.pm, sub database. In that sub, _get_settings($arg, $settings, $logger) is failing. I added a couple of quick logging lines to _get_settings and I'm seeing:

[Dancer2::Plugin::Auth::YARBAC::Provider::Database:31005] error @2016-06-06 08:21:31> $settings->{connections} connections does not exist in /usr/local/share/perl/5.14.2/Dancer2/Core/App.pm l. 836
[Dancer2::Plugin::Auth::YARBAC::Provider::Database:31005] error @2016-06-06 08:21:31> $settings is $VAR1 = {
'charset' => 'utf-8'
}; in /usr/local/share/perl/5.14.2/Dancer2/Core/App.pm l. 836

However, from the 500 error web page, I see this:

```
Settings
appdir => '/var/www/sonic/',
apphandler => 'PSGI',
appname => 'SONIC',
behind_proxy => 0,
charset => 'utf-8',
content_type => 'text/html',
engines => {
logger => {
File => {
file_name => 'sonic.log',
log_dir => '/var/log/sonic'
}
},
session => {
Cookie => {
default_duration => 10800,
secret_key => 'Hidden (looks potentially sensitive)'
}
},
template => {
template_toolkit => {
end_tag => '%>',
start_tag => '<%'
}
}
},
environment => 'development',
host => '0.0.0.0',
layout => 'main',
log => 'debug',
logger => 'file',
no_server_tokens => 0,
plugins => {
Ajax => {
content_type => 'application/json'
},
'Auth::YARBAC' => {
after_login => '/',
after_logout => '/',
login_denied => '/',
no_login_required => '^/login|^/about|^/adduser|^/$',
realms => {
dexter => {
db_connection_name => 'sonic',
provider => 'Database'
/
}
},
Database => {
connections => {
dexter => {
database => 'dexter',
dbi_params => {
AutoCommit => 1,
RaiseError => 1
},
driver => 'mysql',
host => 'localhost',
log_queries => 1,
on_connect_do => [
'SET CHARACTER SET \'utf8\'',
'SET SQL_MODE=\'TRADITIONAL\''
],
password => 'Hidden (looks potentially sensitive)',
port => 3306,
username => 'dexter'
},
sonic => {
database => 'sonic',
dbi_params => {
AutoCommit => 1,
RaiseError => 1
},
driver => 'mysql',
host => 'localhost',
log_queries => 1,
on_connect_do => [
'SET CHARACTER SET \'utf8\'',
'SET SQL_MODE=\'TRADITIONAL\''
],
password => 'Hidden (looks potentially sensitive)',
port => 3306,
username => 'dexter'
}
}
}
},
port => '3000',
public_dir => '/var/www/sonic/public',
route_handlers => [
[
'AutoPage',
1
]
],
session => 'Cookie',
show_errors => 1,
startup_info => 1,
static_handler => 1,
template => 'template_toolkit',
traces => 0,
views => '/var/www/sonic/views',
warnings => 1

Note: Values of 3 sensitive-looking keys hidden
```

So it appears as though the settings are being correctly read from my .yml file. I'm far from an expert Perl developer, so perhaps I just have something screwed up.