/ 
SVG-Sparkline-1
River stage zero No dependents
/ sparkline.cgi

NAME

sparkline.cgi - CGI script for generating SVG-based sparklines

VERSION

This document describes sparkline.cgi version 0.34

SYNOPSIS

http://example.com/cgi-bin/sparkline.cgi?type=Line&values=1,2,3,4,3,2

DESCRIPTION

Since SVG sparklines are useful for display on the web, this CGI script supports creating sparklines on the fly. The CGI returns an SVG file representing the sparkline based on the supplied parameters.

REFERENCING THE SPARKLINE

In theory, you would be able to reference the sparkline call in an HTML img tag to display it. Unfortunately, browser support for SVG in the img tag is currently inconsistent. You can work around this by using the object tag. For example, to render a Line sparkline in an HTML page, you might use the following:

<object type="image/svg+xml" height="12"
    data="http://anomaly.org/cgi-bin/sparkline.cgi?type=Line&sized=0&color=blue&values=10,12,9,11,14,17,20,15,13,8,5,9,13&mark=3:green&mark=high:%23f66&mark=last:%23000&thick=2&padx=4">
</object>

QUERY PARAMETERS

type

The value of this parameter specifies the type of sparkline. It must be one of Area, Bar, Line, RangeArea, RangeBar, or Whisker.

allns

A value of 1 provides all of the xmlns attributes on the root svg element, the default is to only supply the default SVG namespace.

sized

A value of 1 adds the height and width attributes on the root svg element. This is currently the default behavior. A value of 0 removes thos attributes.

bgcolor={color}

Specify a background color for the sparkline. By default, the sparkline will have a transparent background.

padx={length}

Provide {length} pixels of padding on the left and right of the sparkline.

pady={length}

Provide {length} pixels of padding on the top and bottom of the sparkline.

height={length}

Specify the height of the sparkline. The default height is 10 pixels.

width={length}

Specify the width of the sparkling in pixels. The default width depends on the sparkline type and the number of data values.

values={comma separated list of values}

Specify the parameters to display on the sparkline. These values can take one of three forms.

All but RangeArea and RangeBar

Almost all sparkline types support the default data format which is a series of numbers separated by commas. The Whisker type has limits on the values allowed. Other than that, all specified types work the same way.

values=1,2,3,4,5,6,7,8,9
Whisker

The Whisker sparkline type supports another format which is more condensed. This is a series of '+', '-', and '0' characters that represent the high, low, and neutral ticks on the Whisker graph.

values=+--+-0+---+++
RangeArea and RangeBar

These two sparkline types require a pair of data values for each point on the sparkline. To accomplish this, we comma-separated list of pairs of values. Each pair consists of two values separated by a colon, with the smaller value first.

values=1:1,2:4,3:9,4:16,5:25
mark={mark}

This parameter can be supplied multiple times to define multiple marks. Each mark has an index value and a color separated by a colon (or equals). The index value can be either a numeric index or one of the named indexes described in SVG::Sparkline::Manual under mark.

color={color}

Specify the color of the data line.

xscale={length}

Specify the distance between individual data points in the absence of a a width. If neither width or xscale are supplied, the default is 2.

thick={length}

Thickness of the line for those sparklines that have lines. For a Bar or RangeBar sparkline, this specifies the thickness of the bar.

gap={length}

Gap between the bars of the Bar sparkline or the whiskers of the Whisker sparkline.

ON COLORS

When specifying colors for any part of a sparkline, you can use any of the color formats allowed by the SVG recommendation. However, the hexadecimal form poses a problem when used with a CGI script. The # preceding the hexadecimal string must be URL-encoded as %23, otherwise it truncates the URL.

With that caveat, the all color forms listed in "How do I specify a color for the data, background, or marks?" in SVG::Sparkline::Cookbook are supported.

DIAGNOSTICS

The error messages that this script can generate are documented in the various SVG::Sparkline modules. Each is returned with a status code of 400. The error message is returned as HTML content.

CONFIGURATION AND ENVIRONMENT

Although it should be obvious, it is important that the modules that this script depends on are available to the webserver and user the CGI will be run as. Otherwise, the program will not execute.

HOSTED ENVIRONMENT

If you need to run the script in a hosted environment, you may not be able to install the dependencies normally. The recommended approach is the use the local::lib module to configure a local Perl directory for modules the host admin won't or can't install.

Follow the directions in the local::Lib module. Then install SVG and SVG::Sparkline to the local perl directories. Then add the following lines to your copy of sparkline.cgi before the other libraries.

use lib '/home/example/perl5/lib/perl5';
use local::lib;

Obviously, you will need to replace /home/example/perl5 with the path created by the local::lib bootstrap process.

DEPENDENCIES

CGI, SVG::Sparkline, SVG, and the various submodules associated with SVG::Sparkline.

BUGS AND LIMITATIONS

No bugs have been reported.

AUTHOR

G. Wade Johnson gwadej@cpan.org

LICENCE AND COPYRIGHT

Copyright (c) 2013, G. Wade Johnson gwadej@cpan.org. All rights reserved.

This module is free software; you can redistribute it and/or modify it under the same terms as Perl 5.8.0. See perlartistic.

DISCLAIMER OF WARRANTY

BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.