Cache Node.js artifacts from maven-frontend-plugin on CI

[jonkoops]

Closes #31835

[ahus1]

Thank you for this PR. See below for some concerns I have when reviewing this change.

[ahus1]

The cache key is static. Therefore it will be cached once, and the cache is never refreshed for a different node or NPM version, which is then downloaded all the time. Consider adding a combined cache key for npm & node.

This doesn't respect the setting create-cache-if-it-doesnt-exist. This could lead to a situation where there is no frontend being built, and then an empty cache is being created. Please create the cache only when this is set, and provide a download-only version when it is not set.

[jonkoops]

The cache key is static. Therefore it will be cached once, and the cache is never refreshed for a different node or NPM version, which is then downloaded all the time. Consider adding a combined cache key for npm & node.

Done. The key for the cache now includes both the Node.js version and the PNPM version.

This doesn't respect the setting create-cache-if-it-doesnt-exist. This could lead to a situation where there is no frontend being built, and then an empty cache is being created.

Like we discussed offline, the directory paths are very specific and would only create an artifact if the directories exist and contain files. Hence this should not be a problem for this specific cache action.

[jonkoops]

One problem that remains is that it is not possible to exclude the existing artifacts that are cached from org/github/eirslett in the Maven cache due to actions/toolkit#713. Worst case scenario we get two versions of Node.js in the cache, but the fix should still work, just with a little more overhead.

[jonkoops]

@pskopek @stianst since you both have experience with the actions can I ask you for a review as well?

[keycloak-github-bot]

Unreported flaky test detected, please review

[keycloak-github-bot]

Unreported flaky test detected

If the flaky tests below are affected by the changes, please review and update the changes accordingly. Otherwise, a maintainer should report the flaky tests prior to merging the PR.

org.keycloak.testsuite.broker.KcOidcBrokerTest#testPostBrokerLoginFlowWithOTP_bruteForceEnabled

Keycloak CI - Java Distribution IT (windows-latest - temurin - 17)

java.lang.AssertionError: Did not find the event of expected type USER_DISABLED_BY_TEMPORARY_LOCKOUT. Events present: [IDENTITY_PROVIDER_POST_LOGIN_ERROR, IDENTITY_PROVIDER_POST_LOGIN_ERROR, IDENTITY_PROVIDER_POST_LOGIN_ERROR, IDENTITY_PROVIDER_POST_LOGIN_ERROR]
	at org.junit.Assert.fail(Assert.java:89)
	at org.keycloak.testsuite.AssertEvents$ExpectedEvent.assertEvent(AssertEvents.java:410)
	at org.keycloak.testsuite.broker.AbstractAdvancedBrokerTest.testPostBrokerLoginFlowWithOTP_bruteForceEnabled(AbstractAdvancedBrokerTest.java:586)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
...

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