Deflake LeaderElectionTest

Author: brendandburns

extended/src/test/java/io/kubernetes/client/extended/leaderelection/LeaderElectionTest.java

@@ -201,24 +201,29 @@ public void testLeaderElectionWithRenewDeadline() throws InterruptedException {
     List<String> electionHistory = new ArrayList<>();
     List<String> leadershipHistory = new ArrayList<>();
 
+    CountDownLatch testLockAccessLatch = new CountDownLatch(9);
     MockResourceLock mockLock = new MockResourceLock("mock");
     mockLock.renewCountMax = 3;
     mockLock.onCreate =
         record -> {
           electionHistory.add("create record");
           leadershipHistory.add("get leadership");
+          testLockAccessLatch.countDown();
         };
     mockLock.onUpdate =
         record -> {
           electionHistory.add("update record");
+          testLockAccessLatch.countDown();
         };
     mockLock.onChange =
         record -> {
           electionHistory.add("change record");
+          testLockAccessLatch.countDown();
         };
     mockLock.onTryUpdate =
         record -> {
           electionHistory.add("try update record");
+          testLockAccessLatch.countDown();
         };
 
     LeaderElectionConfig leaderElectionConfig = new LeaderElectionConfig();
@@ -244,18 +249,16 @@ record -> {
         });
 
     testLeaderElectionLatch.await(10, SECONDS);
+    testLockAccessLatch.await(10, SECONDS);
 
-    assertHistory(
+    assertWildcardHistory(
         electionHistory,
         "create record",
-        "try update record",
+        "try update record+",
         "update record",
-        "try update record",
+        "try update record+",
         "update record",
-        "try update record",
-        "try update record",
-        "try update record",
-        "try update record");
+        "try update record+");
     assertHistory(leadershipHistory, "get leadership", "start leading", "stop leading");
   }
 
@@ -274,6 +277,36 @@ private void assertHistory(List<String> history, String... expected) {
     }
   }
 
+  // assertWildcardHistory allows for an arbitrary number of repeated entries for an
+  // comparison with a '+' suffix. This allows for a semantic rather than literal
+  // comparison to avoid issues of timing.
+  private void assertWildcardHistory(List<String> history, String... expected) {
+    Assert.assertNotNull(expected);
+    Assert.assertNotNull(history);
+
+    // TODO: This code is too complicated and a little bit buggy, but it works
+    // for the current limited use case. Clean this up!
+    int expectedIx = 0;
+    for (int index = 0; index < history.size(); ++index) {
+      String compare = expected[expectedIx];
+      if (compare.endsWith("+")) {
+        compare = compare.substring(0, compare.length() - 1);
+        if (!history.get(index).equals(compare)) {
+          expectedIx++;
+          compare = expected[expectedIx];
+          expectedIx++;
+        }
+      } else {
+        expectedIx++;
+      }
+      Assert.assertEquals(
+          String.format(
+              "Not equal at index %d, expected %s, got %s", index, compare, history.get(index)),
+          compare,
+          history.get(index));
+    }
+  }
+
   @Test
   public void testLeaderElectionCaptureException() throws ApiException, InterruptedException {
     RuntimeException expectedException = new RuntimeException("noxu");