feat(firebaseai): add responseJsonSchema to GenerationConfig

packages/firebase_ai/firebase_ai/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 3.1.0
+
+ - **FEAT**(firebase_ai): Add support for `responseJsonSchema` in the [GenerationConfig].
+
 ## 3.0.0
 
 > Note: This release has breaking changes.

packages/firebase_ai/firebase_ai/lib/src/api.dart

@@ -998,8 +998,10 @@ final class GenerationConfig extends BaseGenerationConfig {
     super.responseModalities,
     this.responseMimeType,
     this.responseSchema,
+    this.responseJsonSchema,
     this.thinkingConfig,
-  });
+  }) : assert(responseSchema == null || responseJsonSchema == null,
+            'responseSchema and responseJsonSchema cannot both be set.');
 
   /// The set of character sequences (up to 5) that will stop output generation.
   ///
@@ -1020,6 +1022,17 @@ final class GenerationConfig extends BaseGenerationConfig {
   ///   a schema; currently this is limited to `application/json`.
   final Schema? responseSchema;
 
+  /// The response schema as a JSON string.
+  ///
+  /// - Note: This only applies when the [responseMimeType] supports a schema;
+  ///   currently this is limited to `application/json`.
+  ///
+  /// This schema can include more advanced features of JSON than the [Schema]
+  /// class supports.  See [the Gemini
+  /// documentation](https://ai.google.dev/gemini-api/docs/structured-output#json-schema)
+  /// about the limitations of this feature.
+  final String? responseJsonSchema;
+
   /// Config for thinking features.
   ///
   /// An error will be returned if this field is set for models that don't
@@ -1036,6 +1049,8 @@ final class GenerationConfig extends BaseGenerationConfig {
           'responseMimeType': responseMimeType,
         if (responseSchema case final responseSchema?)
           'responseSchema': responseSchema.toJson(),
+        if (responseJsonSchema case final responseJsonSchema?)
+          'responseJsonSchema': responseJsonSchema,
         if (thinkingConfig case final thinkingConfig?)
           'thinkingConfig': thinkingConfig.toJson(),
       };

packages/firebase_ai/firebase_ai/pubspec.yaml

@@ -1,6 +1,6 @@
 name: firebase_ai
 description: Firebase AI SDK.
-version: 3.0.0
+version: 3.1.0
 homepage: https://firebase.google.com/docs/vertex-ai/get-started?platform=flutter
 topics:
   - firebase
@@ -17,7 +17,7 @@ platforms:
 
 environment:
   sdk: '>=3.2.0 <4.0.0'
-  flutter: ">=3.16.0"
+  flutter: '>=3.16.0'
 
 dependencies:
   firebase_app_check: ^0.4.0

packages/firebase_ai/firebase_ai/test/api_test.dart

@@ -442,6 +442,29 @@ void main() {
       });
     });
 
+    test('GenerationConfig toJson with responseJsonSchema', () {
+      const jsonSchema = '{"type": "string", "title": "MyString"}';
+      final config = GenerationConfig(
+        responseMimeType: 'application/json',
+        responseJsonSchema: jsonSchema,
+      );
+      expect(config.toJson(), {
+        'responseMimeType': 'application/json',
+        'responseJsonSchema': jsonSchema,
+      });
+    });
+
+    test(
+        'throws assertion if both responseSchema and responseJsonSchema are provided',
+        () {
+      final schema = Schema.object(properties: {});
+      const jsonSchema = '{"type": "string", "title": "MyString"}';
+      expect(
+          () => GenerationConfig(
+              responseSchema: schema, responseJsonSchema: jsonSchema),
+          throwsA(isA<AssertionError>()));
+    });
+
     test('GenerationConfig toJson with empty stopSequences (omitted)', () {
       final config = GenerationConfig(stopSequences: []);
       expect(config.toJson(), {}); // Empty list for stopSequences is omitted