[Serve] Define BackendConfig protobuf and adapt it in Java

.gitignore

@@ -19,6 +19,7 @@
 /src/ray/object_manager/format/*_generated.h
 /src/ray/raylet/format/*_generated.h
 /java/runtime/src/main/java/io/ray/runtime/generated/*
+/java/serve/src/main/java/io/ray/serve/generated/*
 
 # Files genrated by c++ worker should be ignored.
 /cpp/example/thirdparty/

java/BUILD.bazel

@@ -136,12 +136,20 @@ define_java_module(
 
 define_java_module(
     name = "serve",
+    additional_srcs = [
+        ":serve_java_proto",
+    ],
     define_test_lib = True,
+    exclude_srcs = [
+        "serve/src/main/java/io/ray/serve/generated/*.java",
+    ],
     test_deps = [
         ":io_ray_ray_api",
+        ":io_ray_ray_runtime",
         ":io_ray_ray_serve",
-        "@maven//:org_apache_commons_commons_lang3",
         "@maven//:com_google_guava_guava",
+        "@maven//:com_google_protobuf_protobuf_java",
+        "@maven//:org_apache_commons_commons_lang3",
         "@maven//:org_slf4j_slf4j_api",
         "@maven//:org_testng_testng",
     ],
@@ -150,6 +158,7 @@ define_java_module(
         ":io_ray_ray_api",
         ":io_ray_ray_runtime",
         "@maven//:com_google_guava_guava",
+        "@maven//:com_google_protobuf_protobuf_java",
         "@maven//:org_apache_commons_commons_lang3",
         "@maven//:org_slf4j_slf4j_api",
     ],
@@ -178,6 +187,11 @@ java_proto_compile(
     deps = ["@//src/ray/protobuf:gcs_proto"],
 )
 
+java_proto_compile(
+    name = "serve_java_proto",
+    deps = ["@//src/ray/protobuf:serve_proto"],
+)
+
 filegroup(
     name = "all_java_proto",
     srcs = [
@@ -201,6 +215,7 @@ genrule(
     srcs = [
         ":all_java_proto",
         ":copy_pom_file",
+        ":serve_java_proto",
     ],
     outs = ["cp_java_generated.out"],
     cmd = """
@@ -210,6 +225,10 @@ genrule(
         for f in $(locations //java:all_java_proto); do
             unzip "$$f" -x META-INF/MANIFEST.MF -d "$$WORK_DIR/java/runtime/src/main/java"
         done
+        rm -rf "$$WORK_DIR/java/serve/src/main/java/io/ray/serve/generated"
+        for f in $(locations //java:serve_java_proto); do
+            unzip "$$f" -x META-INF/MANIFEST.MF -d "$$WORK_DIR/java/serve/src/main/java"
+        done
         date > $@
     """,
     local = 1,

java/checkstyle.xml

@@ -29,7 +29,7 @@
     <!-- exclude the generated files from being parsed, which make checkstyle check more fast -->
     <module name="BeforeExecutionExclusionFileFilter">
         <property name="fileNamePattern"
-                  value="io[\\/]ray[\\/].*runtime[\\/]generated[\\/]|RayCall.java|ActorCall.java"/>
+                  value="io[\\/]ray[\\/].*runtime[\\/]generated[\\/]|RayCall.java|ActorCall.java|io[\\/]ray[\\/].*serve[\\/]generated[\\/]"/>
     </module>
 
     <module name="TreeWalker">

java/pom.xml

@@ -255,6 +255,7 @@
                 <exclude>**/ActorCall.java</exclude>
                 <exclude>**/PyActorCall.java</exclude>
                 <exclude>**/runtime/generated/**/*.*</exclude>
+                <exclude>**/serve/generated/**/*.*</exclude>
               </excludes>
               <googleJavaFormat>
                 <version>1.7</version>

java/serve/pom.xml

@@ -32,6 +32,11 @@
   <artifactId>guava</artifactId>
   <version>30.0-jre</version>
 </dependency>
+<dependency>
+  <groupId>com.google.protobuf</groupId>
+  <artifactId>protobuf-java</artifactId>
+  <version>3.16.0</version>
+</dependency>
 <dependency>
   <groupId>org.apache.commons</groupId>
   <artifactId>commons-lang3</artifactId>

java/serve/src/main/java/io/ray/serve/RayServeReplica.java

@@ -9,10 +9,12 @@
 import io.ray.runtime.metric.MetricConfig;
 import io.ray.runtime.metric.Metrics;
 import io.ray.serve.api.Serve;
+import io.ray.serve.generated.BackendConfig;
 import io.ray.serve.poll.KeyListener;
 import io.ray.serve.poll.KeyType;
 import io.ray.serve.poll.LongPollClient;
 import io.ray.serve.poll.LongPollNamespace;
+import io.ray.serve.util.BackendConfigUtil;
 import io.ray.serve.util.LogUtil;
 import io.ray.serve.util.ReflectUtil;
 import java.lang.reflect.Method;
@@ -57,7 +59,7 @@ public RayServeReplica(
     this.replicaTag = Serve.getReplicaContext().getReplicaTag();
     this.callable = callable;
     this.config = backendConfig;
-    this.reconfigure(backendConfig.getUserConfig());
+    this.reconfigure(BackendConfigUtil.getUserConfig(backendConfig));
 
     Map<KeyType, KeyListener> keyListeners = new HashMap<>();
     keyListeners.put(
@@ -190,7 +192,7 @@ private Method getRunnerMethod(Query query) {
   public void drainPendingQueries() {
     while (true) {
       try {
-        Thread.sleep(config.getExperimentalGracefulShutdownWaitLoopS() * 1000);
+        Thread.sleep((long) (config.getExperimentalGracefulShutdownWaitLoopS() * 1000));
       } catch (InterruptedException e) {
         LOGGER.error(
             "Replica {} was interrupted in sheep when draining pending queries", replicaTag);

java/serve/src/main/java/io/ray/serve/RayServeWrappedReplica.java

@@ -3,8 +3,12 @@
 import com.google.common.base.Preconditions;
 import io.ray.api.BaseActorHandle;
 import io.ray.api.Ray;
+import io.ray.runtime.serializer.MessagePackSerializer;
 import io.ray.serve.api.Serve;
+import io.ray.serve.generated.BackendConfig;
+import io.ray.serve.util.BackendConfigUtil;
 import io.ray.serve.util.ReflectUtil;
+import java.io.IOException;
 import java.lang.reflect.InvocationTargetException;
 import java.util.Optional;
 import org.apache.commons.lang3.StringUtils;
@@ -19,11 +23,17 @@ public RayServeWrappedReplica(
       String backendTag,
       String replicaTag,
       String backendDef,
-      Object[] initArgs,
-      BackendConfig backendConfig,
+      byte[] initArgsbytes,
+      byte[] backendConfigBytes,
       String controllerName)
       throws ClassNotFoundException, NoSuchMethodException, InstantiationException,
-          IllegalAccessException, IllegalArgumentException, InvocationTargetException {
+          IllegalAccessException, IllegalArgumentException, InvocationTargetException, IOException {
+
+    // Parse BackendConfig.
+    BackendConfig backendConfig = BackendConfigUtil.parseFrom(backendConfigBytes);
+
+    // Parse init args.
+    Object[] initArgs = parseInitArgs(initArgsbytes, backendConfig);
 
     // Instantiate the object defined by backendDef.
     Class backendClass = Class.forName(backendDef);
@@ -43,6 +53,23 @@ public RayServeWrappedReplica(
     backend = new RayServeReplica(callable, backendConfig, optional.get());
   }
 
+  private Object[] parseInitArgs(byte[] initArgsbytes, BackendConfig backendConfig)
+      throws IOException {
+
+    if (initArgsbytes == null || initArgsbytes.length == 0) {
+      return new Object[0];
+    }
+
+    if (!backendConfig.getIsCrossLanguage()) {
+      // If the construction request is from Java API, deserialize initArgsbytes to Object[]
+      // directly.
+      return MessagePackSerializer.decode(initArgsbytes, Object[].class);
+    } else {
+      // For other language like Python API, not support Array type.
+      return new Object[] {MessagePackSerializer.decode(initArgsbytes, Object.class)};
+    }
+  }
+
   /**
    * The entry method to process the request.
    *
@@ -51,7 +78,7 @@ public RayServeWrappedReplica(
    *     backendDef.
    * @return the result of request being processed
    */
-  public Object handle_request(RequestMetadata requestMetadata, Object[] requestArgs) {
+  public Object handleRequest(RequestMetadata requestMetadata, Object[] requestArgs) {
     return backend.handleRequest(new Query(requestArgs, requestMetadata));
   }
 
@@ -61,7 +88,7 @@ public void ready() {
   }
 
   /** Wait until there is no request in processing. It is used for stopping replica gracefully. */
-  public void drain_pending_queries() {
+  public void drainPendingQueries() {
     backend.drainPendingQueries();
   }
 }

java/serve/src/main/java/io/ray/serve/RequestMetadata.java

@@ -12,7 +12,7 @@ public class RequestMetadata implements Serializable {
 
   private String endpoint;
 
-  private String callMethod = "__call__";
+  private String callMethod = "call";
 
   private String httpMethod;
 

java/serve/src/main/java/io/ray/serve/util/BackendConfigUtil.java

@@ -0,0 +1,76 @@
+package io.ray.serve.util;
+
+import com.google.common.base.Preconditions;
+import com.google.common.collect.Lists;
+import com.google.protobuf.InvalidProtocolBufferException;
+import io.ray.runtime.serializer.MessagePackSerializer;
+import io.ray.serve.RayServeException;
+import io.ray.serve.generated.BackendConfig;
+import io.ray.serve.generated.BackendLanguage;
+
+public class BackendConfigUtil {
+
+  public static BackendConfig parseFrom(byte[] backendConfigBytes)
+      throws InvalidProtocolBufferException {
+
+    // Parse BackendConfig from byte[].
+    BackendConfig inputBackendConfig = BackendConfig.parseFrom(backendConfigBytes);
+    if (inputBackendConfig == null) {
+      return null;
+    }
+
+    // Set default values.
+    BackendConfig.Builder builder = BackendConfig.newBuilder();
+
+    if (inputBackendConfig.getNumReplicas() == 0) {
+      builder.setNumReplicas(1);
+    } else {
+      builder.setNumReplicas(inputBackendConfig.getNumReplicas());
+    }
+
+    Preconditions.checkArgument(
+        inputBackendConfig.getMaxConcurrentQueries() >= 0, "max_concurrent_queries must be >= 0");
+    if (inputBackendConfig.getMaxConcurrentQueries() == 0) {
+      builder.setMaxConcurrentQueries(100);
+    } else {
+      builder.setMaxConcurrentQueries(inputBackendConfig.getMaxConcurrentQueries());
+    }
+
+    builder.setUserConfig(inputBackendConfig.getUserConfig());
+
+    if (inputBackendConfig.getExperimentalGracefulShutdownWaitLoopS() == 0) {
+      builder.setExperimentalGracefulShutdownWaitLoopS(2);
+    } else {
+      builder.setExperimentalGracefulShutdownWaitLoopS(
+          inputBackendConfig.getExperimentalGracefulShutdownWaitLoopS());
+    }
+
+    if (inputBackendConfig.getExperimentalGracefulShutdownTimeoutS() == 0) {
+      builder.setExperimentalGracefulShutdownTimeoutS(20);
+    } else {
+      builder.setExperimentalGracefulShutdownTimeoutS(
+          inputBackendConfig.getExperimentalGracefulShutdownTimeoutS());
+    }
+
+    builder.setIsCrossLanguage(inputBackendConfig.getIsCrossLanguage());
+
+    if (inputBackendConfig.getBackendLanguage() == BackendLanguage.UNRECOGNIZED) {
+      throw new RayServeException(
+          LogUtil.format(
+              "Unrecognized backend language {}. Backend language must be in {}.",
+              inputBackendConfig.getBackendLanguageValue(),
+              Lists.newArrayList(BackendLanguage.values())));
+    } else {
+      builder.setBackendLanguage(inputBackendConfig.getBackendLanguage());
+    }
+
+    return builder.build();
+  }
+
+  public static Object getUserConfig(BackendConfig backendConfig) {
+    if (backendConfig.getUserConfig() == null || backendConfig.getUserConfig().size() == 0) {
+      return null;
+    }
+    return MessagePackSerializer.decode(backendConfig.getUserConfig().toByteArray(), Object.class);
+  }
+}