Fix SSLConfigurationReloaderTests failure tests (#39408)

This change fixes the tests that expect the reload of a
SSLConfiguration to fail. The tests relied on an incorrect assumption
that the reloader only called reload on for an SSLConfiguration if the
key and trust managers were successfully reloaded, but that is not the
case. This change removes the fail call with a wrapped call to the
original method and captures the exception and counts down a latch to
make these tests consistently tested.

Closes #39260

Author: jaymode

x-pack/plugin/core/src/test/java/org/elasticsearch/xpack/core/ssl/SSLConfigurationReloaderTests.java

@@ -48,6 +48,7 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.Consumer;
 
 import static org.hamcrest.Matchers.containsString;
@@ -309,20 +310,31 @@ public void testReloadingKeyStoreException() throws Exception {
         Environment env = randomBoolean() ? null : TestEnvironment.newEnvironment(settings);
         final SSLService sslService = new SSLService(settings, env);
         final SSLConfiguration config = sslService.getSSLConfiguration("xpack.ssl");
+        final AtomicReference<Exception> exceptionRef = new AtomicReference<>();
+        final CountDownLatch latch = new CountDownLatch(1);
         new SSLConfigurationReloader(env, sslService, resourceWatcherService) {
             @Override
             void reloadSSLContext(SSLConfiguration configuration) {
-                fail("reload should not be called! [keystore reload exception]");
+                try {
+                    super.reloadSSLContext(configuration);
+                } catch (Exception e) {
+                    exceptionRef.set(e);
+                    throw e;
+                } finally {
+                    latch.countDown();
+                }
             }
         };
 
         final SSLContext context = sslService.sslContextHolder(config).sslContext();
 
         // truncate the keystore
-        try (OutputStream out = Files.newOutputStream(keystorePath, StandardOpenOption.TRUNCATE_EXISTING)) {
+        try (OutputStream ignore = Files.newOutputStream(keystorePath, StandardOpenOption.TRUNCATE_EXISTING)) {
         }
 
-        // we intentionally don't wait here as we rely on concurrency to catch a failure
+        latch.await();
+        assertNotNull(exceptionRef.get());
+        assertThat(exceptionRef.get().getMessage(), containsString("failed to initialize a KeyManagerFactory"));
         assertThat(sslService.sslContextHolder(config).sslContext(), sameInstance(context));
     }
 
@@ -350,20 +362,31 @@ public void testReloadingPEMKeyConfigException() throws Exception {
         Environment env = randomBoolean() ? null : TestEnvironment.newEnvironment(settings);
         final SSLService sslService = new SSLService(settings, env);
         final SSLConfiguration config = sslService.getSSLConfiguration("xpack.ssl");
+        final AtomicReference<Exception> exceptionRef = new AtomicReference<>();
+        final CountDownLatch latch = new CountDownLatch(1);
         new SSLConfigurationReloader(env, sslService, resourceWatcherService) {
             @Override
             void reloadSSLContext(SSLConfiguration configuration) {
-                fail("reload should not be called! [pem key reload exception]");
+                try {
+                    super.reloadSSLContext(configuration);
+                } catch (Exception e) {
+                    exceptionRef.set(e);
+                    throw e;
+                } finally {
+                    latch.countDown();
+                }
             }
         };
 
         final SSLContext context = sslService.sslContextHolder(config).sslContext();
 
         // truncate the file
-        try (OutputStream os = Files.newOutputStream(keyPath, StandardOpenOption.TRUNCATE_EXISTING)) {
+        try (OutputStream ignore = Files.newOutputStream(keyPath, StandardOpenOption.TRUNCATE_EXISTING)) {
         }
 
-        // we intentionally don't wait here as we rely on concurrency to catch a failure
+        latch.await();
+        assertNotNull(exceptionRef.get());
+        assertThat(exceptionRef.get().getMessage(), containsString("Error parsing Private Key"));
         assertThat(sslService.sslContextHolder(config).sslContext(), sameInstance(context));
     }
 
@@ -385,20 +408,31 @@ public void testTrustStoreReloadException() throws Exception {
         Environment env = randomBoolean() ? null : TestEnvironment.newEnvironment(settings);
         final SSLService sslService = new SSLService(settings, env);
         final SSLConfiguration config = sslService.getSSLConfiguration("xpack.ssl");
+        final AtomicReference<Exception> exceptionRef = new AtomicReference<>();
+        final CountDownLatch latch = new CountDownLatch(1);
         new SSLConfigurationReloader(env, sslService, resourceWatcherService) {
             @Override
             void reloadSSLContext(SSLConfiguration configuration) {
-                fail("reload should not be called! [truststore reload exception]");
+                try {
+                    super.reloadSSLContext(configuration);
+                } catch (Exception e) {
+                    exceptionRef.set(e);
+                    throw e;
+                } finally {
+                    latch.countDown();
+                }
             }
         };
 
         final SSLContext context = sslService.sslContextHolder(config).sslContext();
 
         // truncate the truststore
-        try (OutputStream os = Files.newOutputStream(trustStorePath, StandardOpenOption.TRUNCATE_EXISTING)) {
+        try (OutputStream ignore = Files.newOutputStream(trustStorePath, StandardOpenOption.TRUNCATE_EXISTING)) {
         }
 
-        // we intentionally don't wait here as we rely on concurrency to catch a failure
+        latch.await();
+        assertNotNull(exceptionRef.get());
+        assertThat(exceptionRef.get().getMessage(), containsString("failed to initialize a TrustManagerFactory"));
         assertThat(sslService.sslContextHolder(config).sslContext(), sameInstance(context));
     }
 
@@ -417,10 +451,19 @@ public void testPEMTrustReloadException() throws Exception {
         Environment env = randomBoolean() ? null : TestEnvironment.newEnvironment(settings);
         final SSLService sslService = new SSLService(settings, env);
         final SSLConfiguration config = sslService.getSSLConfiguration("xpack.ssl");
+        final AtomicReference<Exception> exceptionRef = new AtomicReference<>();
+        final CountDownLatch latch = new CountDownLatch(1);
         new SSLConfigurationReloader(env, sslService, resourceWatcherService) {
             @Override
             void reloadSSLContext(SSLConfiguration configuration) {
-                fail("reload should not be called! [pem trust reload exception]");
+                try {
+                    super.reloadSSLContext(configuration);
+                } catch (Exception e) {
+                    exceptionRef.set(e);
+                    throw e;
+                } finally {
+                    latch.countDown();
+                }
             }
         };
 
@@ -433,9 +476,10 @@ void reloadSSLContext(SSLConfiguration configuration) {
         }
         atomicMoveIfPossible(updatedCert, clientCertPath);
 
-        // we intentionally don't wait here as we rely on concurrency to catch a failure
+        latch.await();
+        assertNotNull(exceptionRef.get());
+        assertThat(exceptionRef.get().getMessage(), containsString("failed to initialize a TrustManagerFactory"));
         assertThat(sslService.sslContextHolder(config).sslContext(), sameInstance(context));
-
     }
 
     private void validateSSLConfigurationIsReloaded(Settings settings, Environment env, Consumer<SSLContext> preChecks,