Add an integration test and fix uncovered camelCase JSON issues

FirebaseVertexAI/Sources/GenerationConfig.swift

@@ -162,4 +162,17 @@ public struct GenerationConfig {
 // MARK: - Codable Conformances
 
 @available(iOS 15.0, macOS 12.0, macCatalyst 15.0, tvOS 15.0, watchOS 8.0, *)
-extension GenerationConfig: Encodable {}
+extension GenerationConfig: Encodable {
+  enum CodingKeys: String, CodingKey {
+    case temperature
+    case topP
+    case topK
+    case candidateCount
+    case maxOutputTokens
+    case presencePenalty
+    case frequencyPenalty
+    case stopSequences
+    case responseMIMEType = "responseMimeType"
+    case responseSchema
+  }
+}

FirebaseVertexAI/Sources/Types/Internal/InternalPart.swift

@@ -34,6 +34,11 @@ struct FileData: Codable, Equatable, Sendable {
     self.fileURI = fileURI
     self.mimeType = mimeType
   }
+
+  enum CodingKeys: String, CodingKey {
+    case fileURI = "fileUri"
+    case mimeType
+  }
 }
 
 @available(iOS 15.0, macOS 12.0, macCatalyst 15.0, tvOS 15.0, watchOS 8.0, *)

FirebaseVertexAI/Tests/TestApp/Tests/Integration/IntegrationTests.swift

@@ -41,6 +41,7 @@ final class IntegrationTests: XCTestCase {
 
   var vertex: VertexAI!
   var model: GenerativeModel!
+  var imagenModel: ImagenModel!
   var storage: Storage!
   var userID1 = ""
 
@@ -60,6 +61,9 @@ final class IntegrationTests: XCTestCase {
       toolConfig: .init(functionCallingConfig: .none()),
       systemInstruction: systemInstruction
     )
+    imagenModel = vertex.imagenModel(
+      modelName: "imagen-3.0-fast-generate-001"
+    )
 
     storage = Storage.storage()
   }
@@ -235,6 +239,30 @@ final class IntegrationTests: XCTestCase {
       XCTAssertTrue(String(describing: error).contains("Firebase App Check token is invalid"))
     }
   }
+
+  // MARK: - Imagen
+
+  func testGenerateImage_inlineData() async throws {
+    let imagePrompt = """
+    A realistic photo of a male lion, mane thick and dark, standing proudly on a rocky outcrop
+    overlooking a vast African savanna at sunset. Golden hour light, long shadows, sharp focus on
+    the lion, shallow depth of field, detailed fur texture, DSLR, 85mm lens.
+    """
+
+    let imageResponse = try await imagenModel.generateImages(prompt: imagePrompt)
+
+    XCTAssertNil(imageResponse.raiFilteredReason)
+    XCTAssertEqual(imageResponse.images.count, 1)
+    let image = try XCTUnwrap(imageResponse.images.first)
+
+    let textResponse = try await model.generateContent(
+      InlineDataPart(data: image.data, mimeType: "image/png"),
+      "What is the name of this animal? Answer with the animal name only."
+    )
+
+    let text = try XCTUnwrap(textResponse.text).trimmingCharacters(in: .whitespacesAndNewlines)
+    XCTAssertEqual(text, "Lion")
+  }
 }
 
 extension StorageReference {