Add a configurable process executor based on commons-exec.

5 files changed, 132 insertions, 0 deletions

diff --git a/vespajlib/pom.xml b/vespajlib/pom.xml
index 0282cc94ff6..1d9bdfb452d 100644
--- a/vespajlib/pom.xml
+++ b/vespajlib/pom.xml
@@ -79,6 +79,10 @@
       <artifactId>jackson-databind</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.apache.commons</groupId>
+      <artifactId>commons-exec</artifactId>
+    </dependency>
   </dependencies>
   <build>
     <plugins>
diff --git a/vespajlib/src/main/java/com/yahoo/system/execution/ProcessExecutor.java b/vespajlib/src/main/java/com/yahoo/system/execution/ProcessExecutor.java
new file mode 100644
index 00000000000..564ee5ea3ac
--- /dev/null
+++ b/vespajlib/src/main/java/com/yahoo/system/execution/ProcessExecutor.java
@@ -0,0 +1,79 @@
+// Copyright 2017 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.system.execution;
+
+import org.apache.commons.exec.CommandLine;
+import org.apache.commons.exec.DefaultExecutor;
+import org.apache.commons.exec.ExecuteWatchdog;
+import org.apache.commons.exec.PumpStreamHandler;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+import java.util.Optional;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * @author gjoranv
+ * @author bjorncs
+ */
+public class ProcessExecutor {
+
+    public static class Builder {
+        private final int timeoutSeconds;
+        private int[] successExitCodes;
+
+        public Builder(int timeoutSeconds) {
+            this.timeoutSeconds = timeoutSeconds;
+        }
+
+        public Builder setSuccessExitCodes(int... successExitCodes) {
+            this.successExitCodes = successExitCodes;
+            return this;
+        }
+
+        public ProcessExecutor build() {
+            return new ProcessExecutor(timeoutSeconds, successExitCodes);
+        }
+    }
+
+    private ProcessExecutor(int timeoutSeconds, int[] successExitCodes) {
+        this.timeoutSeconds = timeoutSeconds;
+        this.successExitCodes = successExitCodes;
+    }
+
+    public final int timeoutSeconds;
+    private final int[] successExitCodes;
+
+    public Optional<ProcessResult> execute(String command) throws IOException {
+        return execute(command, null);
+    }
+
+    public Optional<ProcessResult> execute(String command, String processInput) throws IOException {
+        ByteArrayOutputStream processErr = new ByteArrayOutputStream();
+        ByteArrayOutputStream processOut = new ByteArrayOutputStream();
+
+        DefaultExecutor executor = new DefaultExecutor();
+        executor.setStreamHandler(createStreamHandler(processOut, processErr, processInput));
+        ExecuteWatchdog watchDog = new ExecuteWatchdog(TimeUnit.SECONDS.toMillis(timeoutSeconds));
+        executor.setWatchdog(watchDog);
+        executor.setExitValues(successExitCodes);
+
+        int exitCode = executor.execute(CommandLine.parse(command));
+        return (watchDog.killedProcess()) ?
+                Optional.empty() : Optional.of(new ProcessResult(exitCode, processOut.toString(), processErr.toString()));
+    }
+
+    private static PumpStreamHandler createStreamHandler(ByteArrayOutputStream processOut,
+                                                         ByteArrayOutputStream processErr,
+                                                         String input) {
+        if (input != null) {
+            InputStream processInput = new ByteArrayInputStream(input.getBytes(StandardCharsets.UTF_8));
+            return new PumpStreamHandler(processOut, processErr, processInput);
+        } else {
+            return new PumpStreamHandler(processOut, processErr);
+        }
+    }
+
+}
diff --git a/vespajlib/src/main/java/com/yahoo/system/execution/ProcessResult.java b/vespajlib/src/main/java/com/yahoo/system/execution/ProcessResult.java
new file mode 100644
index 00000000000..2f277f83a8c
--- /dev/null
+++ b/vespajlib/src/main/java/com/yahoo/system/execution/ProcessResult.java
@@ -0,0 +1,19 @@
+// Copyright 2017 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.system.execution;
+
+/**
+ * @author bjorncs
+ * @author gjoranv
+ */
+public class ProcessResult {
+    public final String stdOut;
+    public final String stdErr;
+    public final int exitCode;
+
+    public ProcessResult(int exitCode, String stdOut, String stdErr) {
+        this.exitCode = exitCode;
+        this.stdOut = stdOut;
+        this.stdErr = stdErr;
+    }
+
+}
diff --git a/vespajlib/src/main/java/com/yahoo/system/execution/package-info.java b/vespajlib/src/main/java/com/yahoo/system/execution/package-info.java
new file mode 100644
index 00000000000..1f88163d23d
--- /dev/null
+++ b/vespajlib/src/main/java/com/yahoo/system/execution/package-info.java
@@ -0,0 +1,5 @@
+// Copyright 2017 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+@ExportPackage
+package com.yahoo.system.execution;
+
+import com.yahoo.osgi.annotation.ExportPackage;
diff --git a/vespajlib/src/test/java/com/yahoo/system/execution/ProcessExecutorTest.java b/vespajlib/src/test/java/com/yahoo/system/execution/ProcessExecutorTest.java
new file mode 100644
index 00000000000..b12d66853fe
--- /dev/null
+++ b/vespajlib/src/test/java/com/yahoo/system/execution/ProcessExecutorTest.java
@@ -0,0 +1,25 @@
+// Copyright 2017 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.system.execution;
+
+import org.junit.Test;
+
+import java.util.Optional;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author gjoranv
+ */
+public class ProcessExecutorTest {
+
+    @Test
+    public void echo_can_be_executed() throws Exception {
+        final String message = "Hello from executor!";
+        ProcessExecutor executor = new ProcessExecutor.Builder(10).build();
+        Optional<ProcessResult> result = executor.execute("echo " + message);
+        assertTrue(result.isPresent());
+        assertEquals(message, result.get().stdOut.trim());
+        assertEquals("", result.get().stdErr);
+    }
+}