[Vertex AI] Add Firebase Vertex AI API enablement logging

Author: andrewheard

FirebaseVertexAI/Sources/Constants.swift

@@ -21,5 +21,8 @@ import Foundation
 /// Constants associated with the Vertex AI for Firebase SDK.
 enum Constants {
   /// The Vertex AI backend endpoint URL.
+  ///
+  /// TODO(andrewheard): Update to "https://firebasevertexai.googleapis.com" after the Firebase
+  /// Vertex AI API launch.
   static let baseURL = "https://firebaseml.googleapis.com"
 }

FirebaseVertexAI/Sources/Errors.swift

@@ -31,9 +31,14 @@ struct RPCError: Error {
     self.details = details
   }
 
+  // TODO(andrewheard): Remove this method after the Firebase Vertex AI API launch.
   func isFirebaseMLServiceDisabledError() -> Bool {
     return details.contains { $0.isFirebaseMLServiceDisabledErrorDetails() }
   }
+
+  func isFirebaseVertexAIServiceDisabledError() -> Bool {
+    return details.contains { $0.isFirebaseVertexAIServiceDisabledErrorDetails() }
+  }
 }
 
 extension RPCError: Decodable {
@@ -86,17 +91,26 @@ struct ErrorDetails {
     return type == ErrorDetails.errorInfoType
   }
 
+  func isServiceDisabledError() -> Bool {
+    return isErrorInfo() && reason == "SERVICE_DISABLED" && domain == "googleapis.com"
+  }
+
+  // TODO(andrewheard): Remove this method after the Firebase Vertex AI API launch.
   func isFirebaseMLServiceDisabledErrorDetails() -> Bool {
-    guard isErrorInfo() else {
+    guard isServiceDisabledError() else {
       return false
     }
-    guard reason == "SERVICE_DISABLED" else {
+    guard let metadata, metadata["service"] == "firebaseml.googleapis.com" else {
       return false
     }
-    guard domain == "googleapis.com" else {
+    return true
+  }
+
+  func isFirebaseVertexAIServiceDisabledErrorDetails() -> Bool {
+    guard isServiceDisabledError() else {
       return false
     }
-    guard let metadata, metadata["service"] == "firebaseml.googleapis.com" else {
+    guard let metadata, metadata["service"] == "firebasevertexai.googleapis.com" else {
       return false
     }
     return true

FirebaseVertexAI/Sources/GenerativeAIRequest.swift

@@ -31,6 +31,8 @@ public struct RequestOptions {
   let timeout: TimeInterval?
 
   /// The API version to use in requests to the backend.
+  ///
+  /// TODO(andrewheard): Update to "v1beta" after the Firebase Vertex AI API launch.
   let apiVersion = "v2beta"
 
   /// Initializes a request options object.

FirebaseVertexAI/Sources/GenerativeAIService.swift

@@ -266,8 +266,9 @@ struct GenerativeAIService {
   // Log specific RPC errors that cannot be mitigated or handled by user code.
   // These errors do not produce specific GenerateContentError or CountTokensError cases.
   private func logRPCError(_ error: RPCError) {
+    // TODO(andrewheard): Remove this check after the Firebase Vertex AI API launch.
     if error.isFirebaseMLServiceDisabledError() {
-      VertexLog.error(code: .firebaseMLAPIDisabled, """
+      VertexLog.error(code: .firebaseVertexAIAPIDisabled, """
       The Vertex AI for Firebase SDK requires the Firebase ML API `firebaseml.googleapis.com` to \
       be enabled for your project. Get started in the Firebase Console \
       (https://console.firebase.google.com/project/\(projectID)/genai/vertex) or verify that the \
@@ -276,6 +277,15 @@ struct GenerativeAIService {
       \(projectID)).
       """)
     }
+
+    if error.isFirebaseVertexAIServiceDisabledError() {
+      VertexLog.error(code: .firebaseVertexAIAPIDisabled, """
+      The Vertex AI for Firebase SDK requires the Firebase Vertex AI API \
+      `firebasevertexai.googleapis.com` to be enabled for your project. Get started by visiting \
+      the Firebase Console at: \
+      https://console.firebase.google.com/project/\(projectID)/genai/vertex
+      """)
+    }
   }
 
   private func parseResponse<T: Decodable>(_ type: T.Type, from data: Data) throws -> T {

FirebaseVertexAI/Sources/VertexLog.swift

@@ -29,7 +29,7 @@ enum VertexLog {
     case verboseLoggingEnabled = 101
 
     // API Enablement Errors
-    case firebaseMLAPIDisabled = 200
+    case firebaseVertexAIAPIDisabled = 200
 
     // Model Configuration
     case generativeModelInitialized = 1000

FirebaseVertexAI/Tests/Unit/GenerativeModelTests.swift

@@ -453,6 +453,7 @@ final class GenerativeModelTests: XCTestCase {
     }
   }
 
+  // TODO(andrewheard): Remove this test case after the Firebase Vertex AI API launch.
   func testGenerateContent_failure_firebaseMLAPINotEnabled() async throws {
     let expectedStatusCode = 403
     MockURLProtocol
@@ -476,6 +477,30 @@ final class GenerativeModelTests: XCTestCase {
     }
   }
 
+  func testGenerateContent_failure_firebaseVertexAIAPINotEnabled() async throws {
+    let expectedStatusCode = 403
+    MockURLProtocol
+      .requestHandler = try httpRequestHandler(
+        forResource: "unary-failure-firebasevertexai-api-not-enabled",
+        withExtension: "json",
+        statusCode: expectedStatusCode
+      )
+
+    do {
+      _ = try await model.generateContent(testPrompt)
+      XCTFail("Should throw GenerateContentError.internalError; no error thrown.")
+    } catch let GenerateContentError.internalError(error as RPCError) {
+      XCTAssertEqual(error.httpResponseCode, expectedStatusCode)
+      XCTAssertEqual(error.status, .permissionDenied)
+      XCTAssertTrue(error.message
+        .starts(with: "Vertex AI in Firebase API has not been used in project"))
+      XCTAssertTrue(error.isFirebaseMLServiceDisabledError())
+      return
+    } catch {
+      XCTFail("Should throw GenerateContentError.internalError(RPCError); error thrown: \(error)")
+    }
+  }
+
   func testGenerateContent_failure_emptyContent() async throws {
     MockURLProtocol
       .requestHandler = try httpRequestHandler(