Dokka: Generate aggregated API docs

[pocmo]

Currently we create separate API docs for all modules. Because of that you can't jump between modules in the documentation. For example if you are on the page about GeckoEngine you can't get to Engine because this class is in a different module.

┆Issue is synchronized with this Jira Task

[pocmo]

I wasn't able to come up with a satisfying solution on Friday.

The only thing about generating a multi module documentation is this issue in the dokka repository:
Kotlin/dokka#157

One of the mentioned solutions is to create a module just for generating the documentation and letting this module depend on all other modules. This sounds like it's too hacky for us and I was trying to avoid this.

I pushed my state here:
pocmo@f2df8f2

This branch does:

• Generate a multi-module documentation
• Links from classes to the source code on GitHub
• Links to the Android documentation for Android classes
• Links to the Kotlin documentation for Kotlin classes

It does not:

• Major: Know about dependencies. For example the GeckoRuntime parameter in GeckoEngine is labelled as: runtime: <ERROR CLASS>
• Minor: Group by "module"/"artifact" somewhere. You can only browse by package.

Also: telemetry has a different package layout and looks a bit weird in that mix: #698.

[pocmo]

Dokka has a classpath parameter:

    // Manual adding files to classpath
    // This property not overrides classpath collected from kotlinTasks but appends to it
    classpath = [new File("$buildDir/other.jar")]

I assume that setting this to the "classpath" needed to compile the modules would resolve the issue of unknown classes. However I was unable to build this classpath dynamically.

Another thing I tried was adding GeckoView as a dependency to dokkapath but this didn't help resolving the classes.
pocmo@f2df8f2#diff-c197962302397baf3a4cc36463dce5eaR93

[csadilek]

Major: Know about dependencies. For example the GeckoRuntime parameter in GeckoEngine is labelled as: runtime:

I managed to solve this by dynamically constructing the classpath. The main piece of the puzzle was evaluationDependsOnChildren which makes sure the subprojects are evaluated before the dokka task runs. I have not been able to make this work in any other way. Now references to GV and Android SDK types are resolved properly. Sent #723 containing the changes.

[csadilek]

Here's an example site for GeckoEngine:

[pocmo]

@csadilek Awesome. Well done :)