Ensure at least 1 seed configured in remote test (#49389)

Tim-Brooks · web-flow · commit 972219fdad1b · 2019-11-20T11:28:00.000-07:00
This fixes #49384. Currently when we select a random subset of seed nodes from a list, it is possible for 0 seeds to be selected. This test depends on at least 1 seed being selected.
diff --git a/server/src/test/java/org/elasticsearch/transport/RemoteClusterConnectionTests.java b/server/src/test/java/org/elasticsearch/transport/RemoteClusterConnectionTests.java
@@ -461,8 +461,8 @@ public void testConnectedNodesConcurrentAccess() throws IOException, Interrupted
                 discoverableTransports.add(transportService);
             }
 
-            List<String> seedNodes = new CopyOnWriteArrayList<>(randomSubsetOf(discoverableNodes.stream()
-                .map(d -> d.getAddress().toString()).collect(Collectors.toList())));
+            List<String> seedNodes = new CopyOnWriteArrayList<>(randomSubsetOf(randomIntBetween(1, discoverableNodes.size()),
+                discoverableNodes.stream().map(d -> d.getAddress().toString()).collect(Collectors.toList())));
             Collections.shuffle(seedNodes, random());
 
             try (MockTransportService service = MockTransportService.createNewService(Settings.EMPTY, Version.CURRENT, threadPool, null)) {

Original file line number	Diff line number	Diff line change
`@@ -461,8 +461,8 @@ public void testConnectedNodesConcurrentAccess() throws IOException, Interrupted`
`461`	`461`	`discoverableTransports.add(transportService);`
`462`	`462`	`}`
`463`	`463`
`464`		`- List<String> seedNodes = new CopyOnWriteArrayList<>(randomSubsetOf(discoverableNodes.stream()`
`465`		`- .map(d -> d.getAddress().toString()).collect(Collectors.toList())));`
	`464`	`+ List<String> seedNodes = new CopyOnWriteArrayList<>(randomSubsetOf(randomIntBetween(1, discoverableNodes.size()),`
	`465`	`+ discoverableNodes.stream().map(d -> d.getAddress().toString()).collect(Collectors.toList())));`
`466`	`466`	`Collections.shuffle(seedNodes, random());`
`467`	`467`
`468`	`468`	`try (MockTransportService service = MockTransportService.createNewService(Settings.EMPTY, Version.CURRENT, threadPool, null)) {`