Add multi-project test for reindex cancellation

[szybia]

• follow-on from adding reindex cancel endpoint: Add disabled POST _reindex/{taskId}/_cancel API #139211
• create new reindex-management/qa tests module
  • same pattern from other multi-project tests
  • disabled in release builds
• add test that calls cancel from two projects: one that doesn't contain the reindex task and therefore fails, and one that does contain the reindex task and succeeds
  • DEFAULT is implicitly tested in existing IT
  • test fails if i remove the super.match() in previous PR that checks project-ownership in TransportTasksProjectAction

[elasticsearchmachine]

Pinging @elastic/es-distributed-indexing (Team:Distributed Indexing)

[PeteGillinElastic]

Thanks, LGTM, with a couple of comments. The nits you can ignore if you like, but hopefully the suggested base class change will work and simplify this.

[PeteGillinElastic]

You should extend MultiProjectRestTestCase instead. This will save you a bunch of work: you don't need to override shouldConfigureProjects, you don't need removeNonDefaultProjects, and you can use setRequestProjectId as a helper instead of your method of the same name. (I don't think I'm missing any reason why this wouldn't work?)

[szybia]

great point!

i already tried this and found this:

1. MultiProjectRestTestCase exists in test/external-modules/multi-project/src/javaRestTest/...
2. all classes that extend that class exist in same "place":

~/repos/elasticsearch $ rg -l 'extends MultiProjectRestTestCase'
test/external-modules/multi-project/src/javaRestTest/java/org/elasticsearch/action/index/IndexDocumentMultiProjectIT.java
test/external-modules/multi-project/src/javaRestTest/java/org/elasticsearch/action/admin/indices/stats/IndicesStatsMultiProjectIT.java
test/external-modules/multi-project/src/javaRestTest/java/org/elasticsearch/action/admin/indices/SearchMultiProjectIT.java
test/external-modules/multi-project/src/javaRestTest/java/org/elasticsearch/action/admin/indices/IndexMultiProjectCRUDIT.java
test/external-modules/multi-project/src/javaRestTest/java/org/elasticsearch/action/admin/cluster/stats/ClusterStatsMultiProjectIT.java
test/external-modules/multi-project/src/javaRestTest/java/org/elasticsearch/action/admin/cluster/node/stats/NodesStatsMultiProjectIT.java
test/external-modules/multi-project/src/javaRestTest/java/org/elasticsearch/multiproject/MultiProjectRestartIT.java
test/external-modules/multi-project/src/javaRestTest/java/org/elasticsearch/multiproject/action/ProjectCrudActionIT.java
test/external-modules/multi-project/src/javaRestTest/java/org/elasticsearch/multiproject/MultiProjectClusterStateActionIT.java
test/external-modules/multi-project/src/javaRestTest/java/org/elasticsearch/xpack/security/SecurityRolesMultiProjectIT.java

so (as a person still wrapping their mind around gradle/ES deps), commentating:

1. all other multi-project tests i can find (ctrl-f .setting("test.multi_project.enabled", "true")) just use EsRestTestCase
2. importing other modules javaRestTests sounds nonsensical (also can't find an example, but maybe need guidance), and we'd have to export them somehow
3. could do something around putting this into somewhere shared (sounds more sensible), sounds a bit out of scope for me (but i could be being lazy here)

pushed and going to set auto-merge before i sign off and can adjust in a follow-up PR if we need changes here

thoughts? 🙏

[samxbr]

LGTM, thanks!