chore: add skeleton Agent Engine Deployer for ADK Java

dev/src/main/java/com/google/adk/deploy/AgentEngineDeployer.java

@@ -0,0 +1,183 @@
+/*
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.adk.deploy;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.time.Instant;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+/**
+ * Command line application to deploy an ADK Java Agent to Vertex AI Agent Engine (Reasoning
+ * Engine).
+ */
+class AgentEngineDeployer {
+  private static final Logger logger = Logger.getLogger(AgentEngineDeployer.class.getName());
+
+  private final String region;
+  private final String projectId;
+  private final String agentName;
+  private final int serverPort;
+  private final String sourceDir;
+  private final Path tempDir;
+
+  private AgentEngineDeployer(
+      String region,
+      String projectId,
+      String agentName,
+      int serverPort,
+      String sourceDir,
+      Path tempDir) {
+    this.region = region;
+    this.projectId = projectId;
+    this.agentName = agentName;
+    this.serverPort = serverPort;
+    this.sourceDir = sourceDir;
+    this.tempDir = tempDir;
+  }
+
+  /** Creates a temporary Dockerfile and bundles the application for Reasoning Engine deployment. */
+  static Path prepareBundle(int serverPort) throws IOException {
+    Path tempDir = Files.createTempDirectory("agentEngineDeploy");
+    Path dockerfile = tempDir.resolve("Dockerfile");
+
+    String dockerfileContent =
+        String.format(
+            "FROM eclipse-temurin:21-jdk\n"
+                + "WORKDIR /app\n"
+                + "COPY . .\n"
+                + "RUN ./mvnw clean package -DskipTests\n"
+                + "EXPOSE %d\n"
+                + "CMD [\"java\", \"-jar\", \"target/app.jar\"]\n",
+            serverPort);
+
+    Files.writeString(dockerfile, dockerfileContent);
+    logger.info("Prepared Dockerfile at " + dockerfile.toAbsolutePath());
+    return tempDir;
+  }
+
+  /** Orchestrates the deployment process. */
+  public void deploy() throws IOException {
+    logger.info("Starting Agent Engine deployment...");
+    logger.info(
+        String.format(
+            "Deploying Agent '%s' to project '%s' in region '%s'...",
+            agentName, projectId, region));
+
+    // TODO: Integrate with Vertex AI CreateReasoningEngine API client.
+    logger.info("Preparation complete. Skipping actual deployment to Vertex AI for now.");
+  }
+
+  /** Builder for {@link AgentEngineDeployer}. */
+  public static class Builder {
+    private String region;
+    private String projectId;
+    private String agentName;
+    private int serverPort;
+    private String sourceDir;
+
+    public Builder region(String region) {
+      this.region = region;
+      return this;
+    }
+
+    public Builder projectId(String projectId) {
+      this.projectId = projectId;
+      return this;
+    }
+
+    public Builder agentName(String agentName) {
+      this.agentName = agentName;
+      return this;
+    }
+
+    public Builder serverPort(int serverPort) {
+      this.serverPort = serverPort;
+      return this;
+    }
+
+    public Builder sourceDir(String sourceDir) {
+      this.sourceDir = sourceDir;
+      return this;
+    }
+
+    public AgentEngineDeployer build() throws IOException {
+      if (projectId == null || projectId.isEmpty()) {
+        throw new IllegalStateException("Project ID must be specified.");
+      }
+      if (agentName == null || agentName.isEmpty()) {
+        agentName = "ADK Java Agent: " + Instant.now().toString();
+      }
+      if (sourceDir == null || sourceDir.isEmpty()) {
+        sourceDir = System.getProperty("user.dir");
+      }
+      Path tempDir = AgentEngineDeployer.prepareBundle(serverPort);
+      return new AgentEngineDeployer(region, projectId, agentName, serverPort, sourceDir, tempDir);
+    }
+  }
+
+  public static Builder builder() {
+    return new Builder();
+  }
+
+  public static void main(String[] args) {
+    Builder builder = AgentEngineDeployer.builder().region("us-central1").serverPort(8080);
+
+    // Minimal argument parsing logic
+    for (int i = 0; i < args.length; i++) {
+      switch (args[i]) {
+        case "--project":
+          if (i + 1 < args.length) {
+            builder.projectId(args[++i]);
+          }
+          break;
+        case "--region":
+          if (i + 1 < args.length) {
+            builder.region(args[++i]);
+          }
+          break;
+        case "--name":
+          if (i + 1 < args.length) {
+            builder.agentName(args[++i]);
+          }
+          break;
+        case "--port":
+          if (i + 1 < args.length) {
+            builder.serverPort(Integer.parseInt(args[++i]));
+          }
+          break;
+        case "--source-dir":
+          if (i + 1 < args.length) {
+            builder.sourceDir(args[++i]);
+          }
+          break;
+        default:
+          logger.warning("Unknown argument: " + args[i]);
+      }
+    }
+
+    try {
+      AgentEngineDeployer deployer = builder.build();
+      deployer.deploy();
+    } catch (Exception e) {
+      logger.log(Level.SEVERE, "Deployment failed", e);
+      System.exit(1);
+    }
+  }
+}

dev/src/test/java/com/google/adk/deploy/AgentEngineDeployerTest.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.adk.deploy;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assert.assertThrows;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+@RunWith(JUnit4.class)
+public class AgentEngineDeployerTest {
+
+  @Test
+  public void build_withMissingProjectId_throwsException() {
+    AgentEngineDeployer.Builder builder = AgentEngineDeployer.builder();
+    // ProjectId is not set.
+    assertThrows(IllegalStateException.class, builder::build);
+  }
+
+  @Test
+  public void deploy_createsDockerfileWithCorrectPort() throws IOException {
+    int serverPort = 9090;
+
+    Path tempDir = AgentEngineDeployer.prepareBundle(serverPort);
+    Path dockerfile = tempDir.resolve("Dockerfile");
+
+    assertThat(Files.exists(dockerfile)).isTrue();
+    String content = Files.readString(dockerfile);
+    assertThat(content).contains("EXPOSE " + serverPort);
+  }
+}