Route Java worker startup through an app registry

cmd/dev/test.go

@@ -169,7 +169,7 @@ func runJavaHarnessTests(ctx context.Context, repoDir string) error {
 		ctx,
 		harnessDir,
 		"./gradlew",
-		":harness:test",
+		"test",
 	); err != nil {
 		return fmt.Errorf("failed Java harness tests: %w", err)
 	}

workers/build.go

@@ -139,7 +139,7 @@ func (b *Builder) buildJava(ctx context.Context, baseDir string) (sdkbuild.Progr
 		BaseDir:           baseDir,
 		DirName:           b.DirName,
 		Version:           b.SdkOptions.Version,
-		MainClass:         "io.temporal.omes.Main",
+		MainClass:         "io.temporal.omes.apps.Registry",
 		HarnessDependency: "io.temporal:omes:0.1.0",
 		Build:             true,
 		Stdout:            b.stdout,

workers/java/build.gradle

@@ -1,6 +1,7 @@
 plugins {
     id 'java'
     id 'com.diffplug.spotless' version '6.18.0'
+    id 'com.google.protobuf' version '0.9.4'
 }
 
 allprojects {
@@ -24,33 +25,79 @@ spotless {
         target project.fileTree(project.rootDir) {
             include '**/*.java'
             exclude '**/build/**'
-            exclude 'io/temporal/omes/KitchenSink.java'
+            exclude '**/KitchenSink.java'
         }
         googleJavaFormat('1.22.0')
     }
 }
 
 compileJava.dependsOn spotlessJava
+compileJava.dependsOn generateProto
 
 dependencies {
-    implementation project(':harness')
     implementation 'com.google.guava:guava:31.0.1-jre'
     implementation 'com.google.code.gson:gson:2.8.9'
     implementation 'com.jayway.jsonpath:json-path:2.6.0'
     implementation 'io.temporal:temporal-sdk:1.34.0'
     implementation 'org.reflections:reflections:0.10.2'
+    implementation 'ch.qos.logback:logback-classic:1.2.13'
+    implementation 'info.picocli:picocli:4.6.2'
+    implementation 'net.logstash.logback:logstash-logback-encoder:7.4'
+    implementation 'io.micrometer:micrometer-registry-prometheus'
 
     implementation(platform("com.fasterxml.jackson:jackson-bom:2.15.2"))
     implementation "com.fasterxml.jackson.core:jackson-databind"
     implementation "com.fasterxml.jackson.core:jackson-core"
     implementation 'com.google.protobuf:protobuf-java:3.25.5'
     compileOnly 'javax.annotation:javax.annotation-api:1.3.2'
+
+    testImplementation 'io.temporal:temporal-testing:1.34.0'
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.8.1'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.8.1'
 }
 
 sourceSets {
     main {
         java {
-            srcDirs = ['io/temporal/omes']
+            srcDirs = [
+                'io/temporal/omes',
+                "$buildDir/generated/source/proto/main/java",
+                "$buildDir/generated/source/proto/main/grpc",
+            ]
+        }
+        proto {
+            srcDirs = ['../proto/harness/api']
+            include 'api.proto'
+        }
+    }
+    test {
+        java {
+            srcDirs = ['tests']
+        }
+    }
+}
+
+protobuf {
+    protoc {
+        artifact = 'com.google.protobuf:protoc:3.25.5'
+    }
+    plugins {
+        grpc {
+            artifact = 'io.grpc:protoc-gen-grpc-java:1.75.0'
         }
     }
+    generateProtoTasks {
+        all().configureEach { task ->
+            task.builtins {
+                java {}
+            }
+            task.plugins {
+                grpc {}
+            }
+        }
+    }
+}
+
+test {
+    useJUnitPlatform()
 }

workers/java/io/temporal/omes/Main.java

@@ -1,45 +1,11 @@
 package io.temporal.omes;
 
-import io.temporal.client.WorkflowClient;
-import io.temporal.common.converter.ByteArrayPayloadConverter;
-import io.temporal.common.converter.DefaultDataConverter;
-import io.temporal.common.converter.JacksonJsonPayloadConverter;
-import io.temporal.common.converter.NullPayloadConverter;
-import io.temporal.common.converter.PayloadConverter;
-import io.temporal.common.converter.ProtobufJsonPayloadConverter;
-import io.temporal.common.converter.ProtobufPayloadConverter;
-import io.temporal.omes.harness.Harness;
-import io.temporal.omes.harness.HarnessClients;
-import io.temporal.omes.harness.WorkerHarness;
-import io.temporal.worker.Worker;
+import io.temporal.omes.apps.Registry;
 
 public final class Main {
   private Main() {}
 
   public static void main(String... args) throws Exception {
-    Harness.run(app(), args);
-  }
-
-  private static Harness.App app() {
-    return new Harness.App(Main::configureWorker, Main::createClient);
-  }
-
-  private static WorkflowClient createClient(HarnessClients.ClientConfig config) throws Exception {
-    PayloadConverter[] converters = {
-      new NullPayloadConverter(),
-      new ByteArrayPayloadConverter(),
-      new PassthroughDataConverter(),
-      new ProtobufJsonPayloadConverter(),
-      new ProtobufPayloadConverter(),
-      new JacksonJsonPayloadConverter()
-    };
-    return HarnessClients.newWorkflowClient(config, new DefaultDataConverter(converters));
-  }
-
-  private static void configureWorker(
-      WorkflowClient client, Worker worker, WorkerHarness.WorkerContext context) {
-    worker.registerWorkflowImplementationTypes(KitchenSinkWorkflowImpl.class);
-    worker.registerActivitiesImplementations(
-        new ActivitiesImpl(client, context.errOnUnimplemented));
+    Registry.main(args);
   }
 }

workers/java/io/temporal/omes/apps/Registry.java

@@ -0,0 +1,29 @@
+package io.temporal.omes.apps;
+
+import io.temporal.omes.apps.worker.WorkerApp;
+import io.temporal.omes.harness.Harness;
+import java.util.Arrays;
+import java.util.Map;
+
+public final class Registry {
+  private static final String DEFAULT_APP_NAME = "worker";
+  private static final Map<String, Harness.App> REGISTRY = Map.of("worker", WorkerApp.APP);
+
+  private Registry() {}
+
+  public static void main(String... args) throws Exception {
+    String appName = DEFAULT_APP_NAME;
+    String[] harnessArgs = args;
+    if (args.length >= 2 && "--app".equals(args[0])) {
+      appName = args[1];
+      harnessArgs = Arrays.copyOfRange(args, 2, args.length);
+    }
+
+    Harness.App app = REGISTRY.get(appName);
+    if (app == null || appName.isEmpty()) {
+      throw new IllegalArgumentException(String.format("unknown Java worker app %s", appName));
+    }
+
+    Harness.run(app, harnessArgs);
+  }
+}

workers/java/io/temporal/omes/apps/worker/WorkerApp.java

@@ -0,0 +1,43 @@
+package io.temporal.omes.apps.worker;
+
+import io.temporal.client.WorkflowClient;
+import io.temporal.common.converter.ByteArrayPayloadConverter;
+import io.temporal.common.converter.DefaultDataConverter;
+import io.temporal.common.converter.JacksonJsonPayloadConverter;
+import io.temporal.common.converter.NullPayloadConverter;
+import io.temporal.common.converter.PayloadConverter;
+import io.temporal.common.converter.ProtobufJsonPayloadConverter;
+import io.temporal.common.converter.ProtobufPayloadConverter;
+import io.temporal.omes.harness.Harness;
+import io.temporal.omes.harness.HarnessClients;
+import io.temporal.omes.harness.WorkerHarness;
+import io.temporal.omes.workerlib.kitchensink.ActivitiesImpl;
+import io.temporal.omes.workerlib.kitchensink.KitchenSinkWorkflowImpl;
+import io.temporal.omes.workerlib.kitchensink.PassthroughDataConverter;
+import io.temporal.worker.Worker;
+
+public final class WorkerApp {
+  public static final Harness.App APP =
+      new Harness.App(WorkerApp::configureWorker, WorkerApp::createClient);
+
+  private WorkerApp() {}
+
+  private static WorkflowClient createClient(HarnessClients.ClientConfig config) throws Exception {
+    PayloadConverter[] converters = {
+      new NullPayloadConverter(),
+      new ByteArrayPayloadConverter(),
+      new PassthroughDataConverter(),
+      new ProtobufJsonPayloadConverter(),
+      new ProtobufPayloadConverter(),
+      new JacksonJsonPayloadConverter()
+    };
+    return HarnessClients.newWorkflowClient(config, new DefaultDataConverter(converters));
+  }
+
+  private static void configureWorker(
+      WorkflowClient client, Worker worker, WorkerHarness.WorkerContext context) {
+    worker.registerWorkflowImplementationTypes(KitchenSinkWorkflowImpl.class);
+    worker.registerActivitiesImplementations(
+        new ActivitiesImpl(client, context.errOnUnimplemented));
+  }
+}

workers/java/io/temporal/omes/Activities.java → workers/java/io/temporal/omes/workerlib/kitchensink/Activities.java

@@ -1,4 +1,4 @@
-package io.temporal.omes;
+package io.temporal.omes.workerlib.kitchensink;
 
 import io.temporal.activity.ActivityInterface;
 import io.temporal.activity.ActivityMethod;

workers/java/io/temporal/omes/ActivitiesImpl.java → workers/java/io/temporal/omes/workerlib/kitchensink/ActivitiesImpl.java

@@ -1,4 +1,4 @@
-package io.temporal.omes;
+package io.temporal.omes.workerlib.kitchensink;
 
 import io.temporal.activity.Activity;
 import io.temporal.client.WorkflowClient;

workers/java/io/temporal/omes/ClientActionExecutor.java → workers/java/io/temporal/omes/workerlib/kitchensink/ClientActionExecutor.java

@@ -1,4 +1,4 @@
-package io.temporal.omes;
+package io.temporal.omes.workerlib.kitchensink;
 
 import io.temporal.api.common.v1.WorkflowExecution;
 import io.temporal.api.enums.v1.WorkflowIdConflictPolicy;
@@ -8,6 +8,7 @@
 import io.temporal.client.WorkflowOptions;
 import io.temporal.client.WorkflowStub;
 import io.temporal.failure.ApplicationFailure;
+import io.temporal.omes.KitchenSink;
 
 public class ClientActionExecutor {
 

workers/java/io/temporal/omes/KitchenSinkWorkflow.java → workers/java/io/temporal/omes/workerlib/kitchensink/KitchenSinkWorkflow.java

@@ -1,5 +1,6 @@
-package io.temporal.omes;
+package io.temporal.omes.workerlib.kitchensink;
 
+import io.temporal.omes.KitchenSink;
 import io.temporal.workflow.*;
 
 @WorkflowInterface

workers/java/io/temporal/omes/KitchenSinkWorkflowImpl.java → workers/java/io/temporal/omes/workerlib/kitchensink/KitchenSinkWorkflowImpl.java

@@ -1,4 +1,4 @@
-package io.temporal.omes;
+package io.temporal.omes.workerlib.kitchensink;
 
 import com.google.protobuf.util.Durations;
 import io.temporal.activity.ActivityCancellationType;
@@ -15,6 +15,7 @@
 import io.temporal.failure.CanceledFailure;
 import io.temporal.failure.ChildWorkflowFailure;
 import io.temporal.internal.common.SearchAttributesUtil;
+import io.temporal.omes.KitchenSink;
 import io.temporal.workflow.*;
 import java.time.Duration;
 import java.util.ArrayList;

workers/java/io/temporal/omes/PassthroughDataConverter.java → workers/java/io/temporal/omes/workerlib/kitchensink/PassthroughDataConverter.java

@@ -1,4 +1,4 @@
-package io.temporal.omes;
+package io.temporal.omes.workerlib.kitchensink;
 
 import com.google.protobuf.ByteString;
 import io.temporal.api.common.v1.Payload;
@@ -11,7 +11,7 @@
 import java.nio.charset.StandardCharsets;
 import java.util.Optional;
 
-final class PassthroughDataConverter implements PayloadConverter {
+public final class PassthroughDataConverter implements PayloadConverter {
   private static final String METADATA_ENCODING_NAME = "_passthrough";
   private static final ByteString METADATA_ENCODING =
       ByteString.copyFrom(METADATA_ENCODING_NAME, StandardCharsets.UTF_8);

workers/java/settings.gradle

@@ -6,4 +6,3 @@
  */
 
 rootProject.name = 'omes'
-include 'harness'

workers/run.go

@@ -144,8 +144,13 @@ func (r *Runner) Run(ctx context.Context, baseDir string) error {
 			args = append(args, "--app", r.AppName)
 		}
 		args = append(args, "worker")
-	case clioptions.LangDotNet, clioptions.LangRuby, clioptions.LangJava:
-		// .NET, Ruby, and Java just need the harness worker subcommand
+	case clioptions.LangJava:
+		if r.AppName != "" {
+			args = append(args, "--app", r.AppName)
+		}
+		args = append(args, "worker")
+	case clioptions.LangDotNet, clioptions.LangRuby:
+		// .NET and Ruby just need the harness worker subcommand.
 		args = append(args, "worker")
 	}