Use pid identify die-with-dignity process

The die-with-dignity test forces an OOM in Elasticsearch and sees that
it dies appropriately. The test first asserts the correct ES process is
running, and that that process no longer exists after forcing the OOM.
Unfortunately the way of identifying the pid through jps args doesn't
always work (see https://bugs.openjdk.java.net/browse/JDK-7091209).

Instead, this commit passes the known pid for the test cluster through
to the die-with-dignity test, so that it can check for the pid instead
of the command line options.

closes elastic#77282

build-tools/src/main/java/org/elasticsearch/gradle/testclusters/ElasticsearchNode.java

@@ -1409,6 +1409,12 @@ public boolean isProcessAlive() {
         return esProcess.isAlive();
     }
 
+    @Internal
+    public long getPid() {
+        requireNonNull(esProcess, "Can't get pid of " + this + " as it's not started. Does the task have `useCluster` ?");
+        return esProcess.pid();
+    }
+
     void waitForAllConditions() {
         waitForConditions(waitConditions, System.currentTimeMillis(), NODE_UP_TIMEOUT_UNIT.toMillis(NODE_UP_TIMEOUT) +
         // Installing plugins at config time and loading them when nods start requires additional time we need to

test/external-modules/die-with-dignity/build.gradle

@@ -17,6 +17,7 @@ tasks.named("javaRestTest").configure {
   systemProperty 'tests.security.manager', 'false'
   systemProperty 'tests.system_call_filter', 'false'
   nonInputProperties.systemProperty 'log', "${-> testClusters.javaRestTest.singleNode().getServerLog()}"
+  nonInputProperties.systemProperty 'es.pid', "${ -> testClusters.javaRestTest.singleNode().getPid() }"
   systemProperty 'runtime.java.home', BuildParams.runtimeJavaHome
 }
 

test/external-modules/die-with-dignity/src/javaRestTest/java/org/elasticsearch/qa/die_with_dignity/DieWithDignityIT.java

@@ -8,7 +8,6 @@
 
 package org.elasticsearch.qa.die_with_dignity;
 
-import org.apache.lucene.util.LuceneTestCase;
 import org.elasticsearch.client.Request;
 import org.elasticsearch.core.PathUtils;
 import org.elasticsearch.test.rest.ESRestTestCase;
@@ -22,44 +21,18 @@
 import java.util.Iterator;
 import java.util.List;
 
-import static org.hamcrest.Matchers.containsString;
-import static org.hamcrest.Matchers.not;
-
-@LuceneTestCase.AwaitsFix(bugUrl = "https://github.com/elastic/elasticsearch/issues/77282")
 public class DieWithDignityIT extends ESRestTestCase {
 
     public void testDieWithDignity() throws Exception {
         // there should be an Elasticsearch process running with the die.with.dignity.test system property
-        {
-            final String jpsPath = PathUtils.get(System.getProperty("runtime.java.home"), "bin/jps").toString();
-            final Process process = new ProcessBuilder().command(jpsPath, "-v").start();
-
-            boolean found = false;
-            try (InputStream is = process.getInputStream(); BufferedReader in = new BufferedReader(new InputStreamReader(is, "UTF-8"))) {
-                String line;
-                while ((line = in.readLine()) != null) {
-                    if (line.contains("-Ddie.with.dignity.test=true")) {
-                        found = true;
-                        break;
-                    }
-                }
-            }
-            assertTrue(found);
-        }
+        String esPid = System.getProperty("es.pid");
+        assertTrue(javaPidExists(esPid));
 
         expectThrows(IOException.class, () -> client().performRequest(new Request("GET", "/_die_with_dignity")));
 
         // the Elasticsearch process should die and disappear from the output of jps
         assertBusy(() -> {
-            final String jpsPath = PathUtils.get(System.getProperty("runtime.java.home"), "bin/jps").toString();
-            final Process process = new ProcessBuilder().command(jpsPath, "-v").start();
-
-            try (InputStream is = process.getInputStream(); BufferedReader in = new BufferedReader(new InputStreamReader(is, "UTF-8"))) {
-                String line;
-                while ((line = in.readLine()) != null) {
-                    assertThat(line, line, not(containsString("-Ddie.with.dignity.test=true")));
-                }
-            }
+            assertFalse(javaPidExists(esPid));
         });
 
         // parse the logs and ensure that Elasticsearch died with the expected cause
@@ -95,6 +68,22 @@ public void testDieWithDignity() throws Exception {
         }
     }
 
+    private boolean javaPidExists(String expectedPid) throws IOException {
+        final String jpsPath = PathUtils.get(System.getProperty("runtime.java.home"), "bin/jps").toString();
+        final Process process = new ProcessBuilder().command(jpsPath, "-v").start();
+
+        try (InputStream is = process.getInputStream(); BufferedReader in = new BufferedReader(new InputStreamReader(is, "UTF-8"))) {
+            String line;
+            while ((line = in.readLine()) != null) {
+                String foundPid = line.split(" ")[0];
+                if (expectedPid.equals(foundPid)) {
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
     private boolean containsAll(String line, String... subStrings) {
         for (String subString : subStrings) {
             if (line.matches(subString) == false) {