stonecolddevin has asked for the wisdom of the Perl Monks concerning the following question:

UPDATE: Got it working. See readmore for code.

#!C:/xampp/perl/bin/perl.exe -w
use strict;
use CGI;
use CGI::Ajax;
use Template; # for template toolkit support
use CGI::Carp qw[fatalsToBrowser]; #DEBUG ONLY

my $config = {
      INCLUDE_PATH => 'tt/',  # or list ref
};

my $cgi = CGI->new;
my $pjx = CGI::Ajax->new( 'login' => \&do_login );
my $tt  = Template->new($config);

print $pjx->build_html($cgi, \&main_page);

sub do_login {
    my $input = shift;
    # do something with $input
    my $output = $input . " was the input!";
    return( $output );
}

sub main_page {
 
  my $template = 'main.tt';
  my $vars = { title =>'AJAX Test' };
  my $output = '';
  $tt->process($template, $vars, \$output)
       || die $tt->error(), "\n";
  return $output;
 
}

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Hey gang.

This is probably something that's right in front of my face, but I'm attempting to get started on some AJAX using CGI::Ajax and Template (to handle HTML processing). The demo from the docs ran great, however my code is throwing this error:

malformed header from script. Bad header=<html><head><s
+cript type="text: ajax.cgi

[download]

Not only that, but it's returning the HTML as text to the browser.

Here's my code:

#!C:/xampp/perl/bin/perl.exe -w
use strict;
use CGI;
use CGI::Ajax;
use Template; # for template toolkit support
use CGI::Carp qw[fatalsToBrowser]; #DEBUG ONLY

my $config = {
      INCLUDE_PATH => '/tt',  # or list ref
      INTERPOLATE  => 1,               # expand "$var" in plain text
      POST_CHOMP   => 1,               # cleanup whitespace 
      PRE_PROCESS  => 'header',        # prefix each template
      EVAL_PERL    => 1,               # evaluate Perl code blocks
};

my $cgi = CGI->new;
my $pjx = CGI::Ajax->new( 'login' => \&do_login );
my $tt  = Template->new();

print $pjx->build_html($cgi, \&main_page);

sub do_login {
    my $input = shift;
    # do something with $input
    my $output = $input . " was the input!";
    return( $output );
}

sub main_page {
  
  my $template = "main.tt";
  return $tt->process($template, { title =>'AJAX Login'}) or die $tt->
+error;
 
}

[download]

Any ideas? I'm thinking it's something to do with how build_html in CGI::Ajax tries to cope with process in T::T.

Thanks in advance!

meh.

Replies are listed 'Best First'.
Re: CGI::Ajax + Template::Toolkit Question
by chargrill (Parson) on Mar 07, 2007 at 04:16 UTC

    From the error, it looks like you haven't printed out any HTTP headers. Try print header(); before calling print $pjx->build_html. Also, you might want to actually make use of that $config hashref you've setup there in your call to Template->new( $config ).

    Also, if CGI::Ajax is building some HTML, what's Template going to do for you?

    Unfortunately not using CGI::Ajax, but just T::T (which is where I think you're hitting a snag), the following snippet might help:

    #!/usr/bin/perl

use strict;
use warnings;

use Template;
use CGI qw/:standard/;
 # ...
print header(-charset=>'utf-8');

my $vars = { # ... blah blah blah
              };
my $template = Template->new(
  INCLUDE_PATH => '/www/path_to_blah/templates/',
);

$template->process( q/template.tt/, $vars );

    [download]


    --chargrill 
    s**lil*;  $*=join'',sort split q**;  s;.*;grr; &&s+(.(.)).+$2$1+; $; =
qq-$_-;s,.*,ahc,;$,.=chop for split q,,,reverse;print for($,,$;,$*,$/)

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Re: CGI::Ajax + Template::Toolkit Question
by randyk (Parson) on Mar 07, 2007 at 05:12 UTC
    It may be that CGI::Ajax expects build_html to return the html (or updated html) for the page. However, by default, $tt->process($template, $vars) will print the processed output to STDOUT. Try something like the following: 
      sub main_page {
    my $output = '';
    $tt->process($template, $vars, \$output)
       || die $tt->error(), "\n";
    return $output;
  }

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    which will stuff the processed template into $output.
[reply]
[d/l]

      Using randyk's solution, i get the following error (from CGI::Ajax):

      Problems

      with the html-generating function sent to CGI::Ajax object

      Current code:

      sub main_page {
  
  my $output = '';
  my $template = 'main.tt';
  $tt->process($template, $config, \$output)
       || die $tt->error();
  return $output;
 
}

      [download]

      Template code:

      (header.tt)

      <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http:/
+/www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en">
<head>
<title>[% title %]</title>
</head>

<body>

      [download]

      (main.tt)

      <body>

<p>Please log in.</p>
<p>Username: <input type="text" name="username" id="username" /></p>
<p>Password: <input type="password" name="passwd" id="passwd" /></p>
<p><input type="submit" name="login" value="login" onClick="login(['us
+ername'], ['passwd'], ['authenticated']);"/></p>
</body>

</html>

      [download]

      I'm not sure what this error means coming from CGI::Ajax. It's a little unspecific, and I don't see anything in the docs regarding it.

      meh.
[reply]
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        Rather than passing the configuration variables in $config to process, as chargrill noted, you can specify these when creating the $tt object: 
        my $config = {
      INCLUDE_PATH => '/tt', 
      INTERPOLATE  => 1, 
      POST_CHOMP   => 1, 
      PRE_PROCESS  => 'header',
      EVAL_PERL    => 1,
};
my $tt = Template->new($config);

        [download]
        and then specify the variables you want processed in your template in process: 
        sub main_page {
  
  my $output = '';
  my $template = 'main.tt';
  my $vars = { title =>'AJAX Login'};
  $tt->process($template, $vars, \$output)
       || die $tt->error();
  return $output;
}

        [download]
[reply]
[d/l]
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