Custom scripting within Koha

Catalyst Rōpū kohinga training for Koha

Customising Koha with code

Koha provides a number of ways to insert your own script (code) into the system.

• HTML
• CSS
• JS
• Perl

HTML

Refers to the markup of the page.

Creates elements on the page such as text, images, forms, tables, menus and more.

• HTML customisations
• News items
• Pages
• Some system preferences which are yet to be moved into HTML customisations tool

CSS

Refers to style rules (sometimes we will call this theming or branding) including colours, fonts, sizes and more.

• OPACUserCSS
• IntranetUserCSS
• Library specific CSS
• CSS for self-check

JS

Koha supports Javascript and jQuery

Refers to dynamic changes to the page, such as hiding/showing elements, animation and more

• OPACUserJS
• IntranetUserJS
• Library specific JS
• JS for self-check

Perl

Koha is primarily written in a language called Perl

The main way to get code changes into Koha is through the standard upstreaming process (i.e. Bugzilla)

Alternatively, you can write and install plugins which will place custom Perl scripts amongst the standard Koha code

Your Koha vendor must enable this for you on the server

An incomplete list of Koha plugins

Today

We'll look at custom JS, in particular on the staff interface

• IntranetUserJS
• Inline JS through HTML customisations

JS to insert HTML

var useful_link = "/cgi-bin/koha/reports/guided_reports.pl?reports=8&phase=Show SQL";

var

useful_link

"/cgi-bin/koha/reports/guided_reports.pl?reports=8&phase=Show SQL"

Breaking it down...

Initialising a variable

Naming a variable

Strings in speechmarks

Omit base URL for links within Koha

JS to insert HTML

$("element").append("<li><a href='" + useful_link + "'>Report</a></li>");

"element"

useful_link

$

Breaking it down...

Identifier for the element

Refer to variable storing HTML

Insert into the end of the element

Using jQuery

append

"<li><a href='"

HTML to go around the variable

+

Join strings and variables

The element identifier

$("#header_search")

• Use HTML IDs, or tags, or classes
• Use Inspector or View page source to see the HTML
• Be as specific as you need
• Chain together identifiers

$(".circ-button")

$("h3")

$("body#circ_circulation-home h3")

$("body[id='circ_circulation-home'] h3")

Put it all together

var useful_link = "/cgi-bin/koha/reports/guided_reports.pl?reports=8&phase=Show SQL";

$("#header ul").append("<li><a href='" + useful_link + "'>Report</a></li>");

What happens?

Be as specific as you need

var useful_link = "/cgi-bin/koha/reports/guided_reports.pl?reports=8&phase=Show SQL";

$("#header #toplevelmenu").append("<li><a href='" + useful_link + "'>Report</a></li>");

Hiding elements

$("#offline-circulation").hide();

Check first - is there a permission or a system preference I can disable that will hide this module/tool?

$("#menu li:contains('ISBD')").hide();

$(".results_summary.description").hide();

$("#menu li:contains('ISBD'), .results_summary.description").hide();

Default selections

$("#no-autorenew_checkouts") .prop("checked",true);

Functions

$("button").click(function(){
   // do something when a button is clicked
});

$("form").submit(function(){
   // do something when a form is submitted
});

Pop-ups

$("#toolbar #duplicate").click(function(){
  return confirm("Are you sure you want to duplicate this patron?");
});

$("#toolbar #duplicate").click(function(){
  return alert("Duplicating patron, going to patron add form");
});

Apply CSS

$("#patron_messages").css("font-size", "20px");

$("#patron-cardnumber")
.css("color", "blue")
.css("font-weight","800");

Conditions

if ( $("input").val().length == 0 ) {
  // do something if a field is empty
}

if ( $("input").val() .is(":contains('something')) ) {
  // do something if a field contains 'something'
}

if ( $("#checkbox" ).prop("checked") {
  // do something if a checkbox is checked
}

Other resources

• Koha Community jQuery library
• W3 schools has useful resources for the basics
  • jQuery
  • JavaScript
  • HTML
  • CSS
• Stack Overflow for shared solutions - just google what you're trying to do!