Re: [Dancer-users] generating client side code on the server

10 Jan 2011

      On Sat, Jan 8, 2011 at 1:43 AM, Puneet Kishor <punk.kish@gmail.com> wrote:
...
Consider the most basic of workflows
## Perl
   get '/:foo_id.:format' => sub {
       my $foo_id = params->{foo_id};
## SQL
       my $sth = $dbh->prepare(qq{
           SELECT foo FROM table WHERE foo_id = ?
       });
       $sth->execute($foo_id);
       my ($foo) = $sth->fetchrow_array;
to_json({data => $foo});
   };
foo.tt
   ======
   <p>You got <span id="foo">[% foo %]</span></p>
   enter a number <input type="text" id="foo_id" name="foo_id">
   <input type="button" onclick="foo();">
JavaScript
   ==========
   foo = function() {
       $.ajax({
           url     : "/server/" + $("#foo_id").val() + ".json",
           type    : "GET",
           data    : "",
           dataType: "json",
           error   : function() { alert("Error"); },
           success : function(data) {
               $("#foo").html(data.foo);
           }
       });
   }
If I change the table column 'foo' to 'bar' and 'foo_id' to 'bar_id', I
have to change my Perl code (which includes SQL), my template and
JavaScript. Obviously, this can get untenable very quickly as the
application becomes complex. The obvious solution is to generate the
template and the JavaScript on the server side, thereby having to declare
all the names in just one place. I have recently learned of the Perl module
Jemplate that might enable me to do this. But before I commit any cycles to
it, I want to know how the other Dancers handle something like this.
another solution is to use DBIx::Class, where you can declare your schema
with:

__PACKAGE__->add_columns( foo => {name => 'foo'}, ...);

and later change your schema to:

__PACKAGE__->add_columns(foo => {name => 'foo_id'}, ...);

so you don't have to change your code, only your schema.

Re: [Dancer-users] generating client side code on the server

franck