[WICKET-3420] javascript with a less than character ("<") fails to execute when added through a header contribution in ajax response

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.4.15
• Fix Version/s: 1.5-RC3
• Component/s: wicket
• Labels: ajax header-contribution javascript wicket-ajax.js
• Environment: Validated this bug on my dev environment: Windows 7 64 bit using Firefox 4.0beta10 and Chrome 8.
• Assignee: Martin Tzvetanov Grigorov
• Reporter: Randy Schnedler
• Created: 03/Feb/11 19:07
• Updated: 21/Feb/12 14:57
• Resolved: 21/Mar/11 09:26

Description

This is adapted from a wicket users post I made (links are to the same thread in two archive systems):

http://markmail.org/search/?q=wicket%20users%20wicket-ajax.js#query:wicket%20users%20wicket-ajax.js+page:1+mid:rfts3ar3upffhbbt+state:results

http://mail-archives.apache.org/mod_mbox/wicket-users/201102.mbox/%3CAANLkTi=[e-mail]%3E

The problem: I have a panel with this:

<wicket:head>
<script>
if (someVariable < 0)

{ someVariable = 0; }

</script>
</wicket:head>

This script fails to execute when the panel is loaded by ajax. If I replace the less than character "<" with equals "==", then it executes (but of course, this is not what I need).

I tested this in Firefox 4.0b10 and Chrome 8.

After some debugging, it seems to me that this needs to be corrected in wicket-ajax.js. The header contribution is sent to the browser inside of a CDATA section so the "<" character arrives to javascript intact. However, in parsing the script tag, the "<" seems to signal the beginning of an HTML tag that then is considered malformed.

Possible workarounds for apps:

• Invert the logic so a greater-than is used. In my example, this would be: "if (0 > someVariable) {"
• Put the code into a separate JS file (the downside is it requires another network hop from the browser)
• Embed the script in <wicket:panel> rather than <wicket:head> (the disadvantage is the script will be re-sent with the panel content when the panel is re-used on the same page)

Issue Links

• breaks: WICKET-4425 Wicket 1.5 rewrites template content where it should not
• is blocked by: WICKET-3597 Wicket 1.5 RC-3 Bug with conditional comments