Note: I've tried putting the generated files into ./target/generated-resources/ but IntelliJ failed to pick up these resources and put them on the classpath when executing applications/debugging in the IDE (e.g. such as when executing HiveQueryRunner or IcebergQueryRunner). I regularly use those applications for local testing and sometimes use the UI. The only way I was able to get the UI to work successfully in the IDE was by putting the generated files in ./target/classes. This seems like an IntelliJ bug that has been open for quite a few years:

https://youtrack.jetbrains.com/issue/IDEA-107816/generated-resources-are-not-copied-to-the-classpath

@yhwang I took a shot at this. It worked locally but seems the CI doesn't like it. Any thoughts?

the CI failed with this:

[webpack-cli] Error: Cannot find module 'terser-webpack-plugin

I saw you added that dependency to the package.json. haven't had time to try your change yet. I will try it out later today.
The other thing is the -o <dir> option for the yarn install. I am not sure if that works for yarn 1.22.22 since the output directory is specified in the webpack.confg.js

edit

Seems the terser-webpack-plugin is needed by webpack by default. maybe no need to add it to the package.json unless you prefer to pin a specific version.

@ZacBlanco instead of the -o option for yarn install, you can use the following:

index 977ed01e4c..79ffca4911 100644
--- a/presto-main/src/main/resources/webapp/src/webpack.config.js
+++ b/presto-main/src/main/resources/webapp/src/webpack.config.js
@@ -51,7 +51,7 @@ module.exports = (env) => {
             extensions: ['.*', '.js', '.jsx']
         },
         output: {
-            path: path.join(__dirname, '..'),
+            path: path.join(__dirname, '..', '..', '..', '..', '..', 'target', 'classes', 'webapp'),
             filename: path.join('dist', '[name].js'),
         },
         optimization: {

Then the generated js will go to the presto-main/target/classes/webapp. I saw you use ${project.build.directory} in the pom.xml file which is a good change. Just need to figure out how to pass ${project.build.directory} to webpack.config.js to replace the '..', '..', '..', '..', '..', 'target' above. i.e. Having a default value in the webpack.config.js. For maven build, it passes ${project.build.directory} as an alternative value.

I am closing this in favor of the solution in #22745