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Image-Empty-0.20
River stage one • 1 direct dependent • 1 total dependent
/ Image::Empty

NAME

Image::Empty - HTTP response helper for 1x1 empty GIFs or PNGs, for building tracking URLs.

VERSION

Version 0.20

SYNOPSIS

Create 1x1 empty/transparent GIFs or PNGs to use in tracking URLs without the hassle of actually creating and/or loading image data.

Such a basic and common scenario deserves a basic solution.


            

              
              
use Image::Empty;
my $gif = Image::Empty->gif;   # swap for png
print $gif->render;            # HTTP headers and body

METHODS

Class Methods

gif

Returns an instance representing an empty GIF (43 bytes) for use in an HTTP response.


            

              
              
my $gif = Image::Empty->gif;

png

Returns an instance representing an empty PNG (67 bytes) for use in an HTTP response.


            

              
              
my $png = Image::Empty->png;

Instance Methods

render

The render method is used to set the HTTP headers and body.


            

              
              
$gif->render;

With no arguments, returns a string.

Under a CGI environment this would generally be printed directly to STDOUT (ie, the browser).

Chaining methods together can give very concise and compact code.


            

              
              
use Image::Empty;
print Image::Empty->gif->render;

Remember that the render method returns the HTTP headers. The above 2 lines are all you need in a script.

Plack

If you are working with Plack, supply the Plack::Response object to the render method.

The finalized Plack::Response object is returned.

As a quick one-liner...


            

              
              
my $app = sub {
        return Image::Empty->gif->render( Plack::Response->new );
}

It is the same as doing...


            

              
              
my $app = sub {
        my $gif = Image::Empty->gif;
        my $response = Plack::Response->new;
        $response->status(200);
        $response->content_type( $gif->type );
        $response->content_length( $gif->length );
        $response->header( 'Content-Disposition' => $gif->disposition . '; filename="' . $gif->filename . '"' );
        $response->body( $gif->content ); 
        return $response->finalize;
}

Catalyst

If you are working with Catalyst, see Catalyst::View::Image::Empty.

Attributes

type


            

              
              
$gif->type;

Returns the mime/type of the image for use in HTTP headers.

length


            

              
              
$gif->length;

Returns the content length for use in HTTP headers.

disposition


            

              
              
$gif->disposition;

Returns the content disposition for use in HTTP headers.

filename


            

              
              
$gif->filename;

Returns the content filename for use in HTTP headers.

content


            

              
              
$gif->content;

Returns the image data to send in the HTTP response body.

TODO

mod_perl support

AUTHOR

Rob Brown, <rob at intelcompute.com>

BUGS

Please report any bugs or feature requests to bug-image-empty at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Image-Empty. I will be notified, and then you will automatically be notified of progress on your bug as I make changes.

SUPPORT

You can find documentation for this module with the perldoc command.


            

              
              
perldoc Image::Empty

You can also look for information at:

LICENSE AND COPYRIGHT

Copyright 2012 Rob Brown.

This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License.

See http://dev.perl.org/licenses/ for more information.