chore(ai): Add Live API snippets (#15400)

FirebaseAI/Tests/Unit/Snippets/LiveSnippets.swift

@@ -0,0 +1,259 @@
+// 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.
+
+import FirebaseAI
+import FirebaseCore
+import XCTest
+
+// These snippet tests are intentionally skipped in CI jobs; see the README file in this directory
+// for instructions on running them manually.
+
+@available(iOS 15.0, macOS 12.0, macCatalyst 15.0, tvOS 15.0, watchOS 8.0, *)
+@available(watchOS, unavailable)
+final class LiveSnippets: XCTestCase {
+  override func setUpWithError() throws {
+    try FirebaseApp.configureDefaultAppForSnippets()
+  }
+
+  override func tearDown() async throws {
+    await FirebaseApp.deleteDefaultAppForSnippets()
+  }
+
+  func sendAudioReceiveAudio() async throws {
+    // Initialize the Vertex AI Gemini API backend service
+    // Set the location to `us-central1` (the flash-live model is only supported in that location)
+    // Create a `LiveGenerativeModel` instance with the flash-live model (only model that supports
+    // the Live API)
+    let model = FirebaseAI.firebaseAI(backend: .vertexAI(location: "us-central1")).liveModel(
+      modelName: "gemini-2.0-flash-exp",
+      // Configure the model to respond with audio
+      generationConfig: LiveGenerationConfig(
+        responseModalities: [.audio]
+      )
+    )
+
+    do {
+      let session = try await model.connect()
+
+      // Load the audio file, or tap a microphone
+      guard let audioFile = NSDataAsset(name: "audio.pcm") else {
+        fatalError("Failed to load audio file")
+      }
+
+      // Provide the audio data
+      await session.sendAudioRealtime(audioFile.data)
+
+      for try await message in session.responses {
+        if case let .content(content) = message.payload {
+          content.modelTurn?.parts.forEach { part in
+            if let part = part as? InlineDataPart, part.mimeType.starts(with: "audio/pcm") {
+              // Handle 16bit pcm audio data at 24khz
+              playAudio(part.data)
+            }
+          }
+          // Optional: if you don't require to send more requests.
+          if content.isTurnComplete {
+            await session.close()
+          }
+        }
+      }
+    } catch {
+      fatalError(error.localizedDescription)
+    }
+  }
+
+  func sendAudioReceiveText() async throws {
+    // Initialize the Vertex AI Gemini API backend service
+    // Set the location to `us-central1` (the flash-live model is only supported in that location)
+    // Create a `LiveGenerativeModel` instance with the flash-live model (only model that supports
+    // the Live API)
+    let model = FirebaseAI.firebaseAI(backend: .googleAI()).liveModel(
+      modelName: "gemini-live-2.5-flash-preview",
+      // Configure the model to respond with text
+      generationConfig: LiveGenerationConfig(
+        responseModalities: [.text]
+      )
+    )
+
+    do {
+      let session = try await model.connect()
+
+      // Load the audio file, or tap a microphone
+      guard let audioFile = NSDataAsset(name: "audio.pcm") else {
+        fatalError("Failed to load audio file")
+      }
+
+      // Provide the audio data
+      await session.sendAudioRealtime(audioFile.data)
+
+      var outputText = ""
+      for try await message in session.responses {
+        if case let .content(content) = message.payload {
+          content.modelTurn?.parts.forEach { part in
+            if let part = part as? TextPart {
+              outputText += part.text
+            }
+          }
+          // Optional: if you don't require to send more requests.
+          if content.isTurnComplete {
+            await session.close()
+          }
+        }
+      }
+
+      // Output received from the server.
+      print(outputText)
+    } catch {
+      fatalError(error.localizedDescription)
+    }
+  }
+
+  func sendTextReceiveAudio() async throws {
+    // Initialize the Gemini Developer API backend service
+    // Create a `LiveModel` instance with the flash-live model (only model that supports the Live
+    // API)
+    let model = FirebaseAI.firebaseAI(backend: .googleAI()).liveModel(
+      modelName: "gemini-live-2.5-flash-preview",
+      // Configure the model to respond with audio
+      generationConfig: LiveGenerationConfig(
+        responseModalities: [.audio]
+      )
+    )
+
+    do {
+      let session = try await model.connect()
+
+      // Provide a text prompt
+      let text = "tell a short story"
+
+      await session.sendTextRealtime(text)
+
+      for try await message in session.responses {
+        if case let .content(content) = message.payload {
+          content.modelTurn?.parts.forEach { part in
+            if let part = part as? InlineDataPart, part.mimeType.starts(with: "audio/pcm") {
+              // Handle 16bit pcm audio data at 24khz
+              playAudio(part.data)
+            }
+          }
+          // Optional: if you don't require to send more requests.
+          if content.isTurnComplete {
+            await session.close()
+          }
+        }
+      }
+    } catch {
+      fatalError(error.localizedDescription)
+    }
+  }
+
+  func sendTextReceiveText() async throws {
+    // Initialize the Gemini Developer API backend service
+    // Create a `LiveModel` instance with the flash-live model (only model that supports the Live
+    // API)
+    let model = FirebaseAI.firebaseAI(backend: .googleAI()).liveModel(
+      modelName: "gemini-live-2.5-flash-preview",
+      // Configure the model to respond with audio
+      generationConfig: LiveGenerationConfig(
+        responseModalities: [.audio]
+      )
+    )
+
+    do {
+      let session = try await model.connect()
+
+      // Provide a text prompt
+      let text = "tell a short story"
+
+      await session.sendTextRealtime(text)
+
+      for try await message in session.responses {
+        if case let .content(content) = message.payload {
+          content.modelTurn?.parts.forEach { part in
+            if let part = part as? InlineDataPart, part.mimeType.starts(with: "audio/pcm") {
+              // Handle 16bit pcm audio data at 24khz
+              playAudio(part.data)
+            }
+          }
+          // Optional: if you don't require to send more requests.
+          if content.isTurnComplete {
+            await session.close()
+          }
+        }
+      }
+    } catch {
+      fatalError(error.localizedDescription)
+    }
+  }
+
+  func changeVoiceAndLanguage() {
+    let model = FirebaseAI.firebaseAI(backend: .googleAI()).liveModel(
+      modelName: "gemini-live-2.5-flash-preview",
+      // Configure the model to use a specific voice for its audio response
+      generationConfig: LiveGenerationConfig(
+        responseModalities: [.audio],
+        speech: SpeechConfig(voiceName: "Fenrir")
+      )
+    )
+
+    // Not part of snippet
+    silenceWarning(model)
+  }
+
+  func modelParameters() {
+    // ...
+
+    // Set parameter values in a `LiveGenerationConfig` (example values shown here)
+    let config = LiveGenerationConfig(
+      temperature: 0.9,
+      topP: 0.1,
+      topK: 16,
+      maxOutputTokens: 200,
+      responseModalities: [.audio],
+      speech: SpeechConfig(voiceName: "Fenrir")
+    )
+
+    // Initialize the Vertex AI Gemini API backend service
+    // Specify the config as part of creating the `LiveGenerativeModel` instance
+    let model = FirebaseAI.firebaseAI(backend: .googleAI()).liveModel(
+      modelName: "gemini-live-2.5-flash-preview",
+      generationConfig: config
+    )
+
+    // ...
+
+    // Not part of snippet
+    silenceWarning(model)
+  }
+
+  func systemInstructions() {
+    // Specify the system instructions as part of creating the `LiveGenerativeModel` instance
+    let model = FirebaseAI.firebaseAI(backend: .googleAI()).liveModel(
+      modelName: "gemini-live-2.5-flash-preview",
+      systemInstruction: ModelContent(role: "system", parts: "You are a cat. Your name is Neko.")
+    )
+
+    // Not part of snippet
+    silenceWarning(model)
+  }
+
+  private func playAudio(_ data: Data) {
+    // Use AVAudioPlayerNode or something akin to play back audio
+  }
+
+  /// This function only exists to silence the "unused value" warnings.
+  ///
+  /// This allows us to ensure the snippets match devsite.
+  private func silenceWarning(_ model: LiveGenerativeModel) {}
+}

FirebaseAI/Tests/Unit/Snippets/README.md

@@ -5,6 +5,6 @@ documentation continue to compile. They are intentionally skipped in CI but can
 be manually run to verify expected behavior / outputs.
 
 To run the tests, place a valid `GoogleService-Info.plist` file in the
-[`FirebaseVertexAI/Tests/Unit/Resources`](https://github.com/firebase/firebase-ios-sdk/tree/main/FirebaseVertexAI/Tests/Unit/Resources)
+[`FirebaseAI/Tests/Unit/Resources`](https://github.com/firebase/firebase-ios-sdk/tree/main/FirebaseAI/Tests/Unit/Resources)
 folder. They may then be invoked individually or alongside the rest of the unit
 tests in Xcode.