in reply to
Re^2: I LOVE PLACK!!!!
in thread I LOVE PLACK!!!!
I would assume that Plack is amazing to you
Well yeah... sure some of you got into that years ago probably but the future Perl community, us, the noobs, are still finding it and going wow...
Ok I'll put some comments in there...
listing of /var/www/action.psgi
-------------------------------
use UNIVERSAL::require;
##
# awesome peice of kit lets you do stuff like;
#
# my $module = "foo::bar";
# my $module->use();
#
use Plack::Request;
##
#
# gives you alsorts of useful information on a silver
# platter.
#
my $app = sub {
##
# plack compiles the whole program into a subroutine, so
# you gotta hand it a code ref with a specific format to
# its return
#
local $_;
#
# give us our very own private temporary "$_"
# pronounced "it"
#
$_->{'env'} = shift;
$_->{'req'} = Plack::Request->new($_->{'env'});
$_->{'qd'} = $_->{'req'}->parameters->mixed;
#
# it's environment = shift
# it's request = a new Plack request object that has
# been handed a copy of "it's" environment
# it's qd = all the query parameter pairs for it's request
$_->{'qd'}->{'action'} ||= 'default';
#
# make sure it's qd => action has a value or else set to
# 'default'
#
$_->{'qd'}->{'action'} =~ s/\//\:\:/gs;
#
# convert any forward slashes to double colons
# in it's qd => action
#
$_->{'qd'}->{'action'} =
"actions::$_->{'qd'}->{'action'}";
# it's qd => action = "action::" and it's qd => action
#
# (as in concatenate "action" and the value of
# it's qd action)
#
if ($_->{'qd'}->{'action'}->use())
{
#
# test if we are able to use the module name
# for instance if no action=value pair is given
# in the query data, then the action to be called
# will default to "actions::default".
#
# if we have the module ("ie /actions/default.pm")
# then call it's method called "render" to produce
# the return value.
return [ 200,
['Content-Type' => 'text/html'],
[$_->{'qd'}->{'action'}->render()]
];
}
else
{
#else the module doesn't exist, either it's been deleted
#or they have typed the url wrong etc...
return [ 404,
[ 'Content-Type' => 'text/plain' ],
[ 'Error cannot find requested page']
];
}
};
#Simples!!
With that you can put .pm files in a file/directory structure such that a request for action=foo/bar/baz will
automatically load the module baz.pm in the folder foo/bar
That is such a neat little setup!
The simplest action module would then go something like :
sub render { "hello world" }
1;
By using "it" in the PSGI file instead of "my" variables, the values remain available to the action modules thus :
sub render
{
" hello user from $_->{'env'}->{'REMOTE_ADDR'}"
}
1;
