Cross-language invocation Part 1: Java calling Python functions and actors (#4166)

java/test/src/main/java/org/ray/api/test/BaseMultiLanguageTest.java

@@ -0,0 +1,112 @@
+package org.ray.api.test;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+import java.io.File;
+import java.lang.ProcessBuilder.Redirect;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.concurrent.TimeUnit;
+import org.ray.api.Ray;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.testng.SkipException;
+import org.testng.annotations.AfterClass;
+import org.testng.annotations.BeforeClass;
+
+public abstract class BaseMultiLanguageTest {
+
+  private static final Logger LOGGER = LoggerFactory.getLogger(BaseMultiLanguageTest.class);
+
+  private static final String PLASMA_STORE_SOCKET_NAME = "/tmp/ray/test/plasma_store_socket";
+  private static final String RAYLET_SOCKET_NAME = "/tmp/ray/test/raylet_socket";
+
+  /**
+   * Execute an external command.
+   *
+   * @return Whether the command succeeded.
+   */
+  private boolean executeCommand(List<String> command, int waitTimeoutSeconds,
+      Map<String, String> env) {
+    try {
+      LOGGER.info("Executing command: {}", String.join(" ", command));
+      ProcessBuilder processBuilder = new ProcessBuilder(command).redirectOutput(Redirect.INHERIT)
+          .redirectError(Redirect.INHERIT);
+      for (Entry<String, String> entry : env.entrySet()) {
+        processBuilder.environment().put(entry.getKey(), entry.getValue());
+      }
+      Process process = processBuilder.start();
+      process.waitFor(waitTimeoutSeconds, TimeUnit.SECONDS);
+      return process.exitValue() == 0;
+    } catch (Exception e) {
+      throw new RuntimeException("Error executing command " + String.join(" ", command), e);
+    }
+  }
+
+  @BeforeClass
+  public void setUp() {
+    if (!"1".equals(System.getenv("ENABLE_MULTI_LANGUAGE_TESTS"))) {
+      LOGGER.info("Skip Multi-language tests because environment variable "
+          + "ENABLE_MULTI_LANGUAGE_TESTS isn't set");
+      throw new SkipException("Skip test.");
+    }
+
+    // Delete existing socket files.
+    for (String socket : ImmutableList.of(RAYLET_SOCKET_NAME, PLASMA_STORE_SOCKET_NAME)) {
+      File file = new File(socket);
+      if (file.exists()) {
+        file.delete();
+      }
+    }
+
+    // Start ray cluster.
+    String workerOptions =
+        " -classpath " + System.getProperty("java.class.path");
+    final List<String> startCommand = ImmutableList.of(
+        "ray",
+        "start",
+        "--head",
+        "--redis-port=6379",
+        String.format("--plasma-store-socket-name=%s", PLASMA_STORE_SOCKET_NAME),
+        String.format("--raylet-socket-name=%s", RAYLET_SOCKET_NAME),
+        "--load-code-from-local",
+        "--include-java",
+        "--java-worker-options=" + workerOptions
+    );
+    if (!executeCommand(startCommand, 10, getRayStartEnv())) {
+      throw new RuntimeException("Couldn't start ray cluster.");
+    }
+
+    // Connect to the cluster.
+    System.setProperty("ray.redis.address", "127.0.0.1:6379");
+    System.setProperty("ray.object-store.socket-name", PLASMA_STORE_SOCKET_NAME);
+    System.setProperty("ray.raylet.socket-name", RAYLET_SOCKET_NAME);
+    Ray.init();
+  }
+
+  /**
+   * @return The environment variables needed for the `ray start` command.
+   */
+  protected Map<String, String> getRayStartEnv() {
+    return ImmutableMap.of();
+  }
+
+  @AfterClass
+  public void tearDown() {
+    // Disconnect to the cluster.
+    Ray.shutdown();
+    System.clearProperty("ray.redis.address");
+    System.clearProperty("ray.object-store.socket-name");
+    System.clearProperty("ray.raylet.socket-name");
+
+    // Stop ray cluster.
+    final List<String> stopCommand = ImmutableList.of(
+        "ray",
+        "stop"
+    );
+    if (!executeCommand(stopCommand, 10, ImmutableMap.of())) {
+      throw new RuntimeException("Couldn't stop ray cluster");
+    }
+  }
+}

java/test/src/main/java/org/ray/api/test/CrossLanguageInvocationTest.java

@@ -0,0 +1,54 @@
+package org.ray.api.test;
+
+import com.google.common.collect.ImmutableMap;
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Map;
+import org.apache.commons.io.FileUtils;
+import org.ray.api.Ray;
+import org.ray.api.RayObject;
+import org.ray.api.RayPyActor;
+import org.testng.Assert;
+import org.testng.annotations.Test;
+
+public class CrossLanguageInvocationTest extends BaseMultiLanguageTest {
+
+  private static final String PYTHON_MODULE = "test_cross_language_invocation";
+
+  @Override
+  protected Map<String, String> getRayStartEnv() {
+    // Delete and re-create the temp dir.
+    File tempDir = new File(
+        System.getProperty("java.io.tmpdir") + File.separator + "ray_cross_language_test");
+    FileUtils.deleteQuietly(tempDir);
+    tempDir.mkdirs();
+    tempDir.deleteOnExit();
+
+    // Write the test Python file to the temp dir.
+    InputStream in = CrossLanguageInvocationTest.class
+        .getResourceAsStream("/" + PYTHON_MODULE + ".py");
+    File pythonFile = new File(
+        tempDir.getAbsolutePath() + File.separator + PYTHON_MODULE + ".py");
+    try {
+      FileUtils.copyInputStreamToFile(in, pythonFile);
+    } catch (IOException e) {
+      throw new RuntimeException(e);
+    }
+
+    return ImmutableMap.of("PYTHONPATH", tempDir.getAbsolutePath());
+  }
+
+  @Test
+  public void testCallingPythonFunction() {
+    RayObject res = Ray.callPy(PYTHON_MODULE, "py_func", "hello".getBytes());
+    Assert.assertEquals(res.get(), "Response from Python: hello".getBytes());
+  }
+
+  @Test
+  public void testCallingPythonActor() {
+    RayPyActor actor = Ray.createPyActor(PYTHON_MODULE, "Counter", "1".getBytes());
+    RayObject res = Ray.callPy(actor, "increase", "1".getBytes());
+    Assert.assertEquals(res.get(), "2".getBytes());
+  }
+}

java/test/src/main/java/org/ray/api/test/MultiLanguageClusterTest.java

@@ -1,113 +1,18 @@
 package org.ray.api.test;
 
-import com.google.common.collect.ImmutableList;
-import java.io.File;
-import java.lang.reflect.Method;
-import java.util.List;
-import java.util.concurrent.TimeUnit;
 import org.ray.api.Ray;
 import org.ray.api.RayObject;
 import org.ray.api.annotation.RayRemote;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 import org.testng.Assert;
-import org.testng.SkipException;
-import org.testng.annotations.AfterMethod;
-import org.testng.annotations.BeforeMethod;
 import org.testng.annotations.Test;
 
-/**
- * Test starting a ray cluster with multi-language support.
- */
-public class MultiLanguageClusterTest {
-
-  private static final Logger LOGGER = LoggerFactory.getLogger(MultiLanguageClusterTest.class);
-
-  private static final String PLASMA_STORE_SOCKET_NAME = "/tmp/ray/test/plasma_store_socket";
-  private static final String RAYLET_SOCKET_NAME = "/tmp/ray/test/raylet_socket";
+public class MultiLanguageClusterTest extends BaseMultiLanguageTest {
 
   @RayRemote
   public static String echo(String word) {
     return word;
   }
 
-  /**
-   * Execute an external command.
-   *
-   * @return Whether the command succeeded.
-   */
-  private boolean executeCommand(List<String> command, int waitTimeoutSeconds) {
-    try {
-      LOGGER.info("Executing command: {}", String.join(" ", command));
-      Process process = new ProcessBuilder(command).inheritIO().start();
-      process.waitFor(waitTimeoutSeconds, TimeUnit.SECONDS);
-      return process.exitValue() == 0;
-    } catch (Exception e) {
-      throw new RuntimeException("Error executing command " + String.join(" ", command), e);
-    }
-  }
-
-  @BeforeMethod
-  public void setUp(Method method) {
-    String testName = method.getName();
-    if (!"1".equals(System.getenv("ENABLE_MULTI_LANGUAGE_TESTS"))) {
-      LOGGER.info("Skip " + testName +
-          " because env variable ENABLE_MULTI_LANGUAGE_TESTS isn't set");
-      throw new SkipException("Skip test.");
-    }
-
-    // Delete existing socket files.
-    for (String socket : ImmutableList.of(RAYLET_SOCKET_NAME, PLASMA_STORE_SOCKET_NAME)) {
-      File file = new File(socket);
-      if (file.exists()) {
-        file.delete();
-      }
-    }
-
-    // Start ray cluster.
-    String testDir = System.getProperty("user.dir");
-    String workerOptions =
-        " -classpath " + String.format("%s/../../build/java/*:%s/target/*", testDir, testDir);
-    final List<String> startCommand = ImmutableList.of(
-        "ray",
-        "start",
-        "--head",
-        "--redis-port=6379",
-        String.format("--plasma-store-socket-name=%s", PLASMA_STORE_SOCKET_NAME),
-        String.format("--raylet-socket-name=%s", RAYLET_SOCKET_NAME),
-        "--load-code-from-local",
-        "--include-java",
-        "--java-worker-options=" + workerOptions
-    );
-    if (!executeCommand(startCommand, 10)) {
-      throw new RuntimeException("Couldn't start ray cluster.");
-    }
-
-    // Connect to the cluster.
-    System.setProperty("ray.redis.address", "127.0.0.1:6379");
-    System.setProperty("ray.object-store.socket-name", PLASMA_STORE_SOCKET_NAME);
-    System.setProperty("ray.raylet.socket-name", RAYLET_SOCKET_NAME);
-    Ray.init();
-  }
-
-  @AfterMethod
-  public void tearDown() {
-    // Disconnect to the cluster.
-    Ray.shutdown();
-    System.clearProperty("ray.redis.address");
-    System.clearProperty("ray.object-store.socket-name");
-    System.clearProperty("ray.raylet.socket-name");
-
-    // Stop ray cluster.
-    final List<String> stopCommand = ImmutableList.of(
-        "ray",
-        "stop"
-    );
-    if (!executeCommand(stopCommand, 10)) {
-      throw new RuntimeException("Couldn't stop ray cluster");
-    }
-  }
-
   @Test
   public void testMultiLanguageCluster() {
     RayObject<String> obj = Ray.call(MultiLanguageClusterTest::echo, "hello");

java/test/src/main/resources/test_cross_language_invocation.py

@@ -0,0 +1,20 @@
+# This file is used by CrossLanguageInvocationTest.java to test cross-language
+# invocation.
+import ray
+import six
+
+
+@ray.remote
+def py_func(value):
+    assert isinstance(value, bytes)
+    return b"Response from Python: " + value
+
+
+@ray.remote
+class Counter(object):
+    def __init__(self, value):
+        self.value = int(value)
+
+    def increase(self, delta):
+        self.value += int(delta)
+        return str(self.value).encode("utf-8") if six.PY3 else str(self.value)