I'm building a complex content-management system for delivering selected content to Palm handheld devices, and I've run into a problem which may not be possible with given tools, so I'm soliciting some ideas..

What I've done so far, is capture about 885 different URLs of content that users have been using, and stored the url, name, etc. in a database. Nothing magical there. When the user wants to select some content to convert for their Palm, they pick from a list of sites in the database, and are shown a "preview" of what it might look like when it gets onto their handheld in our application.

The problem with the approach I'm using, currently an iframe as shown in the first code snippet below, is that our list of "previews" is subject to whatever HTML the remote site we're pointing to for the iframe decides they want to use, including any broken HTML, maliscious HTML or javascript, meta-refresh tags, popups, and other noise.

# The URL itself is queried from the database above here,
# but that isn't important for this particular explanation
#
# The URL itself is stored in $url_uri from bind_col()
while ($sth->fetch) {
        my $substr_url_uri;  
        $substr_url_uri = length ($url_uri) > 60 
                ? substr($url_uri,0,60) . "..."
                : $url_uri;

        print br(), "\n"x3,    
        start_div({-class=>'urlbox'}), 
        span({-class=>'urlinfo'},
                b("$url_name"), br(),  
                br(), "Current category:",
                        start_span({-class=>'catname'}),
                                $category_name,
                        end_span(), br()x2,

                start_span({-class=>'catlist'}),
                        "Move to new category:", br(),
                        popup_menu("category", \@categories),
        end_span(),
        ), end_div(),  

start_div({-class=>'urlprev'}),
        start_iframe({-src    => "$url_uri",
                -width        => '170',
                -height       => '170',
                -scrolling    => 'no',
                -marginwidth  => '1',
                -marginheight => '1', 
                -frameborder  => '0',}),
        end_iframe,
        end_div(),
}
$sth->finish;
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Obviously this presents a problem when we have a really nice looking interface for the previews, similar to those in this screenshot.

What I'm wondering, is if it is possible to take a screenshot of the content on the remote site, in the same 160x160 window, and present that screenshot to the user in the preview, instead of an iframe pointing directly at the live, remote (raw) content? I know I can fetch the content with LWP::UserAgent, using the following (working) snippet:

   sub fetch_url {
        my $url_uri = shift;

        my $ua       = LWP::UserAgent->new;
        $ua->agent('Mozilla/3.0');
        my $url      = "$url_uri";   
        my $request  = HTTP::Request->new(GET => $url);
        my $response = $ua->request($request);

        # Content itself is in $response->content; here.
        return $response->content;
   }
[download]

Using an image, however, presents us with a few good advantages:

• None of the hrefs and links in the "image" are valid, and can't be clicked, which stops referers from being passed back to the previewed site
• All of the maliscious code is "neutered", so that popups, javascript, meta-refresh tags, etc. are nullified.
• I can add watermarks, titles, captions, etc. to the images in the preview, as well as warnings for sites which may contain "indecent" content.

I can also use LWP::Simple's getstore() function or fetch the content and store it in a local file directly using the snippet above, such as:

   open(CONTENT, ">content.$$") or die $!
   print CONTENT $response->content;
   close CONTENT;
[download]

I'd rather stay away from that for a few reasons:

• Legalities concerning transcoding, storing, or transformation of the content en-route
• Any relative paths to things like images or other content displayed in the page will no longer work

So the question is, does there exist a way to do this programatically?

Is it possible to print the content stored in $response->content; above and create an image out of the contents?

Can I jam the content into some sort of postscript filter, and then print that to an image?

Is there some merlyn column on exactly this topic somewhere on stonehenge?

Has anyone done anything remotely similar to this?