Open Liberty Starter: Gradle 9 and Liberty Gradle Plugin 4.x

[kinueng]

Goal

Introduce a new UX for the Open Liberty starter (start.openliberty.io) that allows users to choose between Gradle 8 and 9. Depending on their choice, the starter will choose between Liberty Gradle Plugin (LGP) 3.x or 4.x.

Reason

The starter currently generates Gradle-based projects using the Liberty Gradle Plugin (LGP) 3.x with Gradle 8. With LGP 4.0.0, support for Gradle 9 was introduced. To support both:

• Users who want to use Gradle 9 need projects generated with LGP 4.x
• Users who need to stay on Gradle 8 should continue using LGP 3.x

Compatibility Constraints

Gradle Version	LGP Version	Minimum Java SE
Gradle 8	LGP 3.x	Java 8
Gradle 9	LGP 4.x	Java 17

Key Constraint: When Gradle 9 is selected:

• Disable Java SE 8 and 11 options and automatically choose 17 as the default choice with Gradle 9
• Show message to user to tell them why certain things are disabled (an existing UX)

LGP compatibility docs https://github.com/OpenLiberty/ci.gradle?tab=readme-ov-file#compatibility--support
Gradle Java support https://docs.gradle.org/current/userguide/compatibility.html

Outstanding Investigation

Need to confirm Jakarta EE and MicroProfile selections are compatible with both LGP 3.x and 4.x

[kinueng]

Design Ideas

Dropdown menu

Radio buttons

[kinueng]

New Alert using existing UX

[kinueng]

One detail that is missing from the screenshots. Gradle Version only appears when users choose Gradle. If users use Maven, the Gradle version is hidden to reduce clutter for users not interested in Gradle.

[navaneethsnair1]

One detail that is missing from the screenshots. Gradle Version only appears when users choose Gradle. If users use Maven, the Gradle version is hidden to reduce clutter for users not interested in Gradle.

But doesn't that sudden hiding of Gradle version look odd when user switches between Maven and Gradle.

1. I suggest either the Gradle version be placed accordingly where other button's position doesn't change. But for smaller screen sizes, this still might be a problem.
2. Or Build tool radio button has 3 options (instead of 2)- Maven, Gradle 9, Gradle 8 which won't affect current UX much

[navaneethsnair1]

@kinueng @cherylking @yeekangc This is a mockup for Gradle 8 and 9 tab in 'Add to Existing Application' section that we discussed in the meeting.

[navaneethsnair1]

Other aspects discussed in the meeting to bring to attention of @yeekangc and @cherylking

• The guide when clicking Try the guide under Gradle in 'Add to existing application' still uses 3.9.5(Gradle 8).
• Is apply plugin: 'liberty' part still relevant for Gradle 9?

[cherylking]

@venmanyarun @sajeerzeji See questions in last comment and respond please.

[venmanyarun]

Other aspects discussed in the meeting to bring to attention of @yeekangc and @cherylking

• The guide when clicking Try the guide under Gradle in 'Add to existing application' still uses 3.9.5(Gradle 8).
• Is apply plugin: 'liberty' part still relevant for Gradle 9?

• apply plugin: 'liberty' part is still relevant for Gradle 9
• I will look into the guide to see the changes to migrate to gradle 9 with version 4.0.0
• Update :- PR Raised for Gradle 9 support :- Lgp version upgrade to 9 guide-gradle-intro#219

[kinueng]

@navaneethsnair1 Since we are showing Gradle 8 and 9 tabs in the Add to existing application section, let's go with showing radio buttons for Gradle 8 and 9 for the Create a starter application section.

[yeekangc]

I lean toward the first one in #4186 (comment).

For #4186 (comment), can we offer two tabs under "Gradle"?

[cherylking]

For image 1 in this comment, does the Gradle version drop down only appear after they select the Gradle radio button? I think that would make the most sense. At the very least, the drop down needs to be disabled when the Gradle radio button is not selected. I prefer having the dropdown for selecting the version. I foresee needing something similar for Maven version when we start supporting Maven 4 potentially.

If you cannot do YK's suggestion of two tabs under "Gradle", you could have two sections on a single Gradle tab with clear headings that one is for Gradle 8 and the other for Gradle 9.