NMS-18978: Don't load ui-components menu JS on login and password gate; fix wallpaper edge gap

[synqotik]

NMS-18978: Don't load ui-components menu JS on login and password gate; fix wallpaper edge gap

The ui-components CSS and JS, which are used for the menu/sidemenu that appear on JSP pages, were included in the JSP login and password gate pages, even though there's no menu on those pages.

This removes the JS references so those 2 pages are cleaner. There's a small tradeoff where the menu JS won't be loaded until the user logs in and gets to the main page vs. having already been cached, but this seems like a reasonable one-time-per-session tradeoff. Initially we also removed the CSS, but it's actually needed for some styling on those pages.

Also, fixed an edge gap with the OpenNMS Horizon wallpaper on those 2 pages, where a thin white bar across the top and left edges was being displayed. The image was fixed and now the wallpaper fills the entire window neatly.

Summary

includes/bootstrap.jsp adds two links to the <head> of every page:

• a stylesheet for the Vue menu bundle, ui-components/assets/index.css
• a modulepreload for ui-components/assets/index.js

This includes login.jsp and account/selfService/passwordGate.jsp, which never mount the menu. The links were added in NMS-19975 (#8670). NMS-20180 (#8792) then kept them on the login page on purpose, so the bundle would be cached before the first page after login.

This PR drops the modulepreload on those two pages, so neither one loads the menu bundle's JavaScript. They keep the stylesheet, because they rely on it for font size and other styling.

Changes

• includes/bootstrap.jsp: new nomenujs option. When set, the page skips the menu bundle's modulepreload link; the stylesheet is always emitted. Pages can set it either way they already set quiet: as an include param or as a Bootstrap flag. The option is documented in the parameter notes at the top of the file, and the head comment is updated.
• login.jsp: Bootstrap.flags("quiet", "nomenujs").
• passwordGate.jsp: <jsp:param name="nomenujs" value="true" />.
• WebappIT: verifyLoginPageDoesNotExecuteMenuBundle is now verifyLoginPageDoesNotReferenceMenuBundleJs. It asserts that login.jsp contains no reference to ui-components/assets/index.js. It also checks that the login form rendered and that index.css is still linked, so the test can't pass on an error page or after a URL change.

Wallpaper edge gap

The login and password gate pages both showed a thin white bar along the top and left edges of the background. This is not caused by the menu changes above.

• Cause: images/wallpapers/background_dark.png has a 1–2px partly transparent border: the top 2 rows, the bottom row and the left column. Layout is not involved, because .login-page sits at (0,0) and fills the viewport. background-size: cover scales the image about 1.28×, so the white <body> shows through as a 2–3px strip on top and 1–2px on the left. The bottom edge is cropped off by cover, so it never shows.
• Fix: the border is cropped off the image, which goes from 1284×857 to 1283×854. There are no CSS changes. The remaining pixels are fully opaque and identical to the original's interior. The file is re-encoded without interlacing and shrinks from 474 KB to 257 KB.

Not changed

• Other quiet pages still get the preload. The new flag is opt-in and only these two pages use it.
• /ui-components/assets/** stays reachable without logging in. That rule from NMS-20174/NMS-20180 still guards against a browser caching an auth redirect as the bundle. The WebappIT tests for anonymous asset access are unchanged.
• The inline theme script still runs on every page. It sets the open-light/open-dark class on <html> before first paint and doesn't reference ui-components.
• Trade-off: the first page after login no longer finds the menu bundle already cached, so it fetches it like any other JSP page does.

External References

• Jira (Issue Tracker): https://opennms.atlassian.net/browse/NMS-18978

[marshallmassengill]

Approving but two findings:

1. The login and password gate pages will look different. The menu stylesheet the PR removes also sets the font on the input boxes, their labels and the error message text. Without it those fall back to the plain system font, and the login inputs get slightly tighter line spacing. The description doesn't mention this, so ask for before-and-after screenshots.
2. The new flag has a trap, but nothing is affected yet. nomenuassets removes the menu's stylesheet but not the menu script. A page that set it without quiet would show the menu with no styling.

[synqotik]

Approving but two findings:

1. The login and password gate pages will look different. The menu stylesheet the PR removes also sets the font on the input boxes, their labels and the error message text. Without it those fall back to the plain system font, and the login inputs get slightly tighter line spacing. The description doesn't mention this, so ask for before-and-after screenshots.

2. The new flag has a trap, but nothing is affected yet. nomenuassets removes the menu's stylesheet but not the menu script. A page that set it without quiet would show the menu with no styling.

Re 1., updated to only remove the JS but keep the CSS, so styling remains unchanged.

Re 2., note the flag has been changed to nomenujs (since we are loading some assets, i.e. the CSS). Re setting one flag without the other (i.e. nomenujs without quiet), it's acceptable, someone would have to make an odd decision to do that. Eventually all the JSP will be phased out anyway.

[marshallmassengill]

I think this is good to go!