Add support for Gradle

[marshalhayes]

Related to an existing integration?

Yes

Existing integration

CommunityToolkit.Aspire.Hosting.Java

Overview

The Java integration currently only supports building with Maven. Gradle is another popular choice in the Java ecosystem, and would likely be worth supporting as well.

Usage example

Usage could look like this:

// apphost.cs
builder.AddJavaApp("spring-app", "./spring-app")
   .WithGradleBuild();

WithGradleBuild could accept optional options as well similar to how WithMavenBuild does.

Breaking change?

No

Alternatives

Outside of creating a custom solution, I don't know of any alternatives that allow Gradle builds.

Additional context

No response

Help us help you

Yes, I'd like to be assigned to work on this item

[aaronpowell]

I've had a bit of a look through the PR but I thought I'd kick off a discussion here rather than within the PR so that it can avoid getting muddled.

Just for some context, the Java integration was one of the first ones that was added, back in the very early days of Aspire, and as a result, some of the design of it does not necessarily reflect the design of Aspire as of today.

One part that I would argue is no longer ideally designed is the Maven build, and this naturally influences the design for Gradle. As the current design is handling Process.Start itself, we have a level of opacity that is introduced with this, and as such we don't see log output making it way to Aspire appropriately.

With this proposed work, I think it'd be a good opportunity to address that design and align more like is done with the Node.js and Python integrations in Aspire, with how they use npm/yarn/uv/pip, or how Go works with go.mod in this repo. The way these are implemented is that the installer (or build toolchain in this case) is a resource itself, so when you do WithGradleBuild is would create a new JavaBuildResource that uses gradle as the executable (or maven if you used WithMavenBuild). These resources are then managed by Aspire itself, they appear in the dashboard, you get their output in the logs, they can be restarted via the dashboard, and a whole host of other benefits.

If you're up for is @marshalhayes - I'd really love to see this undertaken. It'll help modernise the Java integration and better support the Java community who want to leverage Aspire.

[marshalhayes]

This is a great idea, and I'd love to work on it! I'll take a look at the other integrations you mentioned and see if I can align with those.

[aaronpowell]

The Golang integration is probably an easy starting point if you don't want to dive into the Aspire source code. You could also look back at the last pre-13 release of the Community Toolkit, as that's when we still had the yarn/pnpm/etc. integrations here before they moved to Aspire core.