cli kill background process and all its sub-processes

Author: MykolaGolubyev

webtau-cli/src/main/java/org/testingisdocumenting/webtau/cli/ProcessBackgroundRunResult.java

@@ -16,11 +16,16 @@
 
 package org.testingisdocumenting.webtau.cli;
 
+import java.io.IOException;
+import java.lang.reflect.Field;
+
 public class ProcessBackgroundRunResult {
     private final Process process;
     private final StreamGobbler outputGobbler;
     private final StreamGobbler errorGobbler;
 
+    private final int pid;
+
     private final Thread consumeErrorThread;
     private final Thread consumeOutThread;
 
@@ -30,6 +35,7 @@ public ProcessBackgroundRunResult(Process process,
                                       Thread consumeErrorThread,
                                       Thread consumeOutThread) {
         this.process = process;
+        this.pid = extractPid(process);
         this.outputGobbler = outputGobbler;
         this.errorGobbler = errorGobbler;
         this.consumeErrorThread = consumeErrorThread;
@@ -43,7 +49,13 @@ public Process getProcess() {
     public void destroy() {
         outputGobbler.close();
         errorGobbler.close();
-        process.destroy();
+
+        try {
+            ProcessUtils.kill(pid);
+            process.waitFor();
+        } catch (InterruptedException | IOException e) {
+            throw new RuntimeException(e);
+        }
     }
 
     public StreamGobbler getOutputGobbler() {
@@ -69,4 +81,20 @@ public ProcessRunResult createRunResult() {
                 outputGobbler.getException(),
                 errorGobbler.getException());
     }
+
+    /**
+     * we need to support java 8, pid() is added in java 9
+     * so using hacks to get to pid value
+     * @param process process
+     * @return pid
+     */
+    private static int extractPid(Process process) {
+        try {
+            Field pidField = process.getClass().getDeclaredField("pid");
+            pidField.setAccessible(true);
+            return (int) pidField.get(process);
+        } catch (NoSuchFieldException | IllegalAccessException e) {
+            throw new RuntimeException(e);
+        }
+    }
 }

webtau-cli/src/main/java/org/testingisdocumenting/webtau/cli/ProcessUtils.java

@@ -19,6 +19,7 @@
 import java.io.IOException;
 import java.nio.file.Paths;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.stream.Collectors;
@@ -46,6 +47,10 @@ public static ProcessRunResult run(String command, Map<String, String> env) thro
         }
     }
 
+    public static void kill(int pid) throws IOException {
+        run("pkill -TERM -P " + pid, Collections.emptyMap());
+    }
+
     public static ProcessBackgroundRunResult runInBackground(String command, Map<String, String> env) throws IOException {
         List<String> splitCommandWithPrefix = prefixCommandWithPathAndSplit(command);
         ProcessBuilder processBuilder = new ProcessBuilder(splitCommandWithPrefix);