feat: [vertexai] infer location and project when user doesn't specify…

… them.

PiperOrigin-RevId: 635997756

java-vertexai/google-cloud-vertexai/src/main/java/com/google/cloud/vertexai/Constants.java

@@ -20,6 +20,10 @@
 public final class Constants {
   // Constants for VertexAI class
   public static final String USER_AGENT_HEADER = "model-builder";
+  public static final String DEFAULT_LOCATION = "us-central1";
+  public static final String GOOGLE_CLOUD_REGION = "GOOGLE_CLOUD_REGION";
+  public static final String CLOUD_ML_REGION = "CLOUD_ML_REGION";
+  public static final String GOOGLE_CLOUD_PROJECT = "GOOGLE_CLOUD_PROJECT";
 
   private Constants() {}
 }

java-vertexai/google-cloud-vertexai/src/main/java/com/google/cloud/vertexai/VertexAI.java

@@ -27,6 +27,7 @@
 import com.google.api.gax.rpc.FixedHeaderProvider;
 import com.google.api.gax.rpc.HeaderProvider;
 import com.google.auth.Credentials;
+import com.google.auth.oauth2.GoogleCredentials;
 import com.google.cloud.vertexai.api.LlmUtilityServiceClient;
 import com.google.cloud.vertexai.api.LlmUtilityServiceSettings;
 import com.google.cloud.vertexai.api.PredictionServiceClient;
@@ -67,6 +68,21 @@ public class VertexAI implements AutoCloseable {
   private final transient Supplier<PredictionServiceClient> predictionClientSupplier;
   private final transient Supplier<LlmUtilityServiceClient> llmClientSupplier;
 
+  static Optional<String> getEnvironmentVariable(String envKey) {
+    return Optional.ofNullable(System.getenv(envKey));
+  }
+
+  static GoogleCredentials getGoogleCredentialsFromCredentialsProvider(
+      CredentialsProvider credentialsProvider) {
+    try {
+      final GoogleCredentials googleCredentials =
+          (GoogleCredentials) credentialsProvider.getCredentials();
+      return googleCredentials;
+    } catch (Exception e) {
+      throw new IllegalArgumentException(e);
+    }
+  }
+
   /**
    * Constructs a VertexAI instance.
    *
@@ -85,6 +101,26 @@ public VertexAI(String projectId, String location) {
         /* llmClientSupplierOpt= */ Optional.empty());
   }
 
+  /**
+   * Constructs a VertexAI instance with no arguments. SDK will infer location from runtime
+   * environment. If there is no location inferred from runtime environment, SDK will default
+   * location to `us-central1`. SDK will infer projectId from GoogleCredentials. If there is
+   * GoogleCredentials at runtime, SDK will throw IllegalArgumentException
+   *
+   * @throws java.lang.IllegalArgumentException
+   */
+  public VertexAI() {
+    this(
+        null,
+        null,
+        Transport.GRPC,
+        ImmutableList.of(),
+        /* credentials= */ Optional.empty(),
+        /* apiEndpoint= */ Optional.empty(),
+        /* predictionClientSupplierOpt= */ Optional.empty(),
+        /* llmClientSupplierOpt= */ Optional.empty());
+  }
+
   private VertexAI(
       String projectId,
       String location,
@@ -98,12 +134,8 @@ private VertexAI(
       throw new IllegalArgumentException(
           "At most one of Credentials and scopes should be specified.");
     }
-    checkArgument(!Strings.isNullOrEmpty(projectId), "projectId can't be null or empty");
-    checkArgument(!Strings.isNullOrEmpty(location), "location can't be null or empty");
     checkNotNull(transport, "transport can't be null");
-
-    this.projectId = projectId;
-    this.location = location;
+    this.location = Strings.isNullOrEmpty(location) ? inferLocation() : location;
     this.transport = transport;
 
     if (credentials.isPresent()) {
@@ -118,13 +150,15 @@ private VertexAI(
                   .build();
     }
 
+    this.projectId = Strings.isNullOrEmpty(projectId) ? inferProjectId() : projectId;
     this.predictionClientSupplier =
         Suppliers.memoize(predictionClientSupplierOpt.orElse(this::newPredictionServiceClient));
 
     this.llmClientSupplier =
         Suppliers.memoize(llmClientSupplierOpt.orElse(this::newLlmUtilityClient));
 
-    this.apiEndpoint = apiEndpoint.orElse(String.format("%s-aiplatform.googleapis.com", location));
+    this.apiEndpoint =
+        apiEndpoint.orElse(String.format("%s-aiplatform.googleapis.com", this.location));
   }
 
   /** Builder for {@link VertexAI}. */
@@ -141,8 +175,6 @@ public static class Builder {
     private Supplier<LlmUtilityServiceClient> llmClientSupplier;
 
     public VertexAI build() {
-      checkNotNull(projectId, "projectId must be set.");
-      checkNotNull(location, "location must be set.");
 
       return new VertexAI(
           projectId,
@@ -339,6 +371,41 @@ private LlmUtilityServiceClient newLlmUtilityClient() {
     }
   }
 
+  private String inferProjectId() {
+    final String projectNotFoundErrorMessage =
+        ("Unable to infer your project. Please provide a project Id by one of the following:"
+            + "\n- Passing a constructor argument by using new VertexAI(String projectId, String"
+            + " location)"
+            + "\n- Setting project using 'gcloud config set project my-project'"
+            + "\n- Setting a GCP environment variable"
+            + "\n- To create a Google Cloud project, please follow guidance at"
+            + " https://developers.google.com/workspace/guides/create-project");
+    final Optional<String> projectIdOptional =
+        getEnvironmentVariable(Constants.GOOGLE_CLOUD_PROJECT);
+    if (projectIdOptional.isPresent()) {
+      return projectIdOptional.get();
+    }
+    String projectId;
+    try {
+      final GoogleCredentials googleCredentials =
+          getGoogleCredentialsFromCredentialsProvider(this.credentialsProvider);
+      projectId = googleCredentials.getQuotaProjectId();
+    } catch (IllegalArgumentException e) {
+      throw new IllegalArgumentException(projectNotFoundErrorMessage, e);
+    }
+    if (Strings.isNullOrEmpty(projectId)) {
+      throw new IllegalArgumentException(projectNotFoundErrorMessage);
+    }
+
+    return projectId;
+  }
+
+  private String inferLocation() {
+    return getEnvironmentVariable(Constants.GOOGLE_CLOUD_REGION)
+        .orElse(
+            getEnvironmentVariable(Constants.CLOUD_ML_REGION).orElse(Constants.DEFAULT_LOCATION));
+  }
+
   private LlmUtilityServiceSettings getLlmUtilityServiceClientSettings() throws IOException {
     LlmUtilityServiceSettings.Builder settingsBuilder;
     if (transport == Transport.REST) {

java-vertexai/google-cloud-vertexai/src/test/java/com/google/cloud/vertexai/FakeGoogleCredentials.java

@@ -0,0 +1,17 @@
+package com.google.cloud.vertexai;
+
+import com.google.auth.oauth2.GoogleCredentials;
+
+/** */
+public final class FakeGoogleCredentials extends GoogleCredentials {
+  private String testProject;
+
+  FakeGoogleCredentials(String testProject) {
+    this.testProject = testProject;
+  }
+
+  @Override
+  public String getQuotaProjectId() {
+    return this.testProject;
+  }
+}