Ronald Cruz created WICKET-6841:
-----------------------------------
Summary: Evaluation order of dependent JS in Ajax request
Key: WICKET-6841
URL: https://issues.apache.org/jira/browse/WICKET-6841
Project: Wicket
Issue Type: Bug
Components: wicket-core
Affects Versions: 9.0.0, 9.1.0
Environment: Linux - Ubuntu 19.1, JDK 14
Reporter: Ronald Cruz
Attachments: wicket-js-order.zip
Starting in Wicket 9, an issue cropped up with how JS is evaluated when loaded
through Ajax. It appears as though JS in the component is evaluated before the
references in <wicket:head> or #renderHead() are resolved. This leads to
initialization and reference errors in the first rendering if said JS in the
component references the libraries in the header. Subsequent usages are fine as
the referenced libraries are then cached.
I'm not familiar with Wicket internals, but this to me seems related to what
Martin brought up in
[WICKET-6840|https://issues.apache.org/jira/browse/WICKET-6840]. The comment
reads:
"Before WICKET-6703 Wicket was using <prepend-evaluation> elements in the Ajax
XML response, which were processed before any component replacement. After
WICKET-6703 we use <header-contribution> for both prepend and append JS. With
the change above the issue is worked around but the prepend JS contributed by
AjaxIndicatorAppender is executed *after* the component replacements."
I've attached a sample quickstart that is a simplified version of the charting
issue I mentioned having in that ticket. It is a custom component that pulls a
simple JS library in the header and calls it inline. The issue can be observed
through the browser JS console when clicking the link.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
