More Gripes and Misunderstandings about Dancer

It has been suggested that I'm not using MVC separation, which is fair, as I don't really see MVC separation. I found the POD for Dancer::Plugin::Database, and have modified my package to use it. weather is the old one, weather2 is the new one using the plugin.

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1. package TestApp ;  
2. use Dancer ':syntax' ;  
3. use Dancer::Plugin::Database ;  
4. use lib '/home/jacoby/lib' ;  
5. use MyDB 'db_connect' ;  
6. use DateTime ;  
7. use Data::Dumper ;  
8.   
9. our $VERSION = '0.1' ;  
10.   
11. get '/' => sub {  
12.     template 'index' ;  
13.     } ;  
14.    
15. get '/weather' => sub {  
16.     my $dbh = db_connect() ;  
17.     my $sql = <<SQL;  
18.     # Last Eight Hours  
19.     SELECT  time , AVG( temp_f )  
20.     FROM weather WHERE zip = "47909"  
21.     AND HOUR( TIMEDIFF( SYSDATE() , time ) ) < 9  
22.     GROUP BY HOUR(time)  
23.     ORDER BY time  
24. SQL  
25.     my $hr = $dbh->selectall_arrayref( $sql ) or croak $dbh->errstr ;  
26.     my @hr ;  
27.     for my $point ( @$hr ) {  
28.         my ( $time, $temp ) = @$point ;  
29.         my @time = split /\D+/ ,  $time ;  
30.         my $dt = DateTime->new(  
31.             year  => $time[0] ,  
32.             month => $time[1] ,  
33.             day   => $time[2] ,  
34.             hour => $time[3] ,  
35.             minute => $time[4] ,  
36.             second => $time[5] ,  
37.             ) ;  
38.         my $data ;  
39.         $data->{ time } = $dt->format_cldr( 'h:mm a' ) ;  
40.         $data->{ temp } = sprintf '%.1f', $temp ;  
41.         next if $data->{ time } !~ /00/ ;  
42.         push @hr, $data ;  
43.         }  
44.     my $string = 'Temperature in West Lafayette for the last 8 hours' ;  
45.     my $hr_ptr = \@hr ;  
46.     template 'weather' , {  
47.         string => $string ,  
48.         weather => $hr_ptr  
49.         } ;  
50.     } ;  
51.   
52. get '/weather2' => sub {  
53.     my $string = 'Temperature in West Lafayette for the last 8 hours' ;  
54.     my $sth = database->prepare(  
55.         'SELECT  time , AVG( temp_f ) temp  
56.         FROM weather WHERE zip = "47909"  
57.         AND HOUR( TIMEDIFF( SYSDATE() , time ) ) < 9  
58.         GROUP BY HOUR(time)  
59.         ORDER BY time '  
60.         ) ;  
61.     $sth->execute( ) ;  
62.     template 'weather' , {  
63.         string => $string ,  
64.         xxx => $sth->fetchall_arrayref( ) ,  
65.         } ;  
66.     } ;  
67.   
68. true ;  

package TestApp ;
use Dancer ':syntax' ;
use Dancer::Plugin::Database ;
use lib '/home/jacoby/lib' ;
use MyDB 'db_connect' ;
use DateTime ;
use Data::Dumper ;

our $VERSION = '0.1' ;

get '/' => sub {
    template 'index' ;
    } ;
 
get '/weather' => sub {
    my $dbh = db_connect() ;
    my $sql = <<SQL;
    # Last Eight Hours
    SELECT  time , AVG( temp_f )
    FROM weather WHERE zip = "47909"
    AND HOUR( TIMEDIFF( SYSDATE() , time ) ) < 9
    GROUP BY HOUR(time)
    ORDER BY time
SQL
    my $hr = $dbh->selectall_arrayref( $sql ) or croak $dbh->errstr ;
    my @hr ;
    for my $point ( @$hr ) {
        my ( $time, $temp ) = @$point ;
        my @time = split /\D+/ ,  $time ;
        my $dt = DateTime->new(
            year  => $time[0] ,
            month => $time[1] ,
            day   => $time[2] ,
            hour => $time[3] ,
            minute => $time[4] ,
            second => $time[5] ,
            ) ;
        my $data ;
        $data->{ time } = $dt->format_cldr( 'h:mm a' ) ;
        $data->{ temp } = sprintf '%.1f', $temp ;
        next if $data->{ time } !~ /00/ ;
        push @hr, $data ;
        }
    my $string = 'Temperature in West Lafayette for the last 8 hours' ;
    my $hr_ptr = \@hr ;
    template 'weather' , {
        string => $string ,
        weather => $hr_ptr
        } ;
    } ;

get '/weather2' => sub {
    my $string = 'Temperature in West Lafayette for the last 8 hours' ;
    my $sth = database->prepare(
        'SELECT  time , AVG( temp_f ) temp
        FROM weather WHERE zip = "47909"
        AND HOUR( TIMEDIFF( SYSDATE() , time ) ) < 9
        GROUP BY HOUR(time)
        ORDER BY time '
        ) ;
    $sth->execute( ) ;
    template 'weather' , {
        string => $string ,
        xxx => $sth->fetchall_arrayref( ) ,
        } ;
    } ;

true ;

I have been pointed to http://search.cpan.org/~xsawyerx/Dancer-1.3091/lib/Dancer/Tutorial.pod, and, beyond my wanting to be more specific in the munging of the data, weather is very similar to "Our First Route Handler". (How I store some data is not necessarily how I want to display some data.)

weather2 uses http://search.cpan.org/~bigpresh/Dancer-Plugin-Database-1.60/lib/Dancer/Plugin/Database.pm and you can see that there's much less code in there. The stuff I put into  MyDB exists in Dancer::Plugin::Database, and I probably could mess with the data before sending it on, instead of hooking up $sth->fetchall_arrayref() to the output.

The big thing I see here, which I could do something about with weather but probably not with the plugin-using weather2, is the SQL code being here. I would much rather shove that SQL off into a library somewhere, which I've done elsewhere, than have it at this point. But maybe, that's an aspect of me not really getting the MVC thing yet.