feat(openai_dart): Support different embedding response formats (#180)

packages/openai_dart/README.md

@@ -237,7 +237,7 @@ final res = await client.createEmbedding(
     input: EmbeddingInput.string('The food was delicious and the waiter...'),
   ),
 );
-print(res.data.first.embedding);
+print(res.data.first.embeddingVector);
 // [0.002253932, -0.009333183, 0.01574578, -0.007790351, -0.004711035, ...]
 ```
 
@@ -251,6 +251,20 @@ print(res.data.first.embedding);
 - `EmbeddingInput.arrayString(['input'])`: batch of string inputs.
 - `EmbeddingInput.array([[...]])`: batch of tokenized inputs.
 
+You can also request the embedding vector encoded as a base64 string:
+
+```dart
+final res = await client.createEmbedding(
+  request: CreateEmbeddingRequest(
+    model: EmbeddingModel.string('text-embedding-ada-002'),
+    input: EmbeddingInput.string('The food was delicious and the waiter...'),
+    encodingFormat: EmbeddingEncodingFormat.base64,
+  ),
+);
+print(res.data.first.embeddingVectorBase64);
+// tLYTOzXqGLxL/YA8M0b/uwdfmrsdNXM8iJIfvEOOHL3IJeK7Ok3rv...
+```
+
 ### Fine-tuning
 
 Manage fine-tuning jobs to tailor a model to your specific training data.

packages/openai_dart/example/openai_dart_example.dart

@@ -57,7 +57,7 @@ Future<void> _embeddings(final OpenAIClient client) async {
       input: EmbeddingInput.string('The food was delicious and the waiter...'),
     ),
   );
-  print(res.data.first.embedding);
+  print(res.data.first.embeddingVector);
 }
 
 Future<void> _fineTuning(final OpenAIClient client) async {

packages/openai_dart/lib/openai_dart.dart

@@ -2,5 +2,6 @@
 library;
 
 export 'src/client.dart';
+export 'src/extensions.dart';
 export 'src/generated/client.dart' show OpenAIClientException;
 export 'src/generated/schema/schema.dart';

packages/openai_dart/lib/src/extensions.dart

@@ -0,0 +1,31 @@
+import 'generated/schema/schema.dart';
+
+extension EmbeddingX on Embedding {
+  /// The embedding vector as a list of doubles.
+  ///
+  /// You can only use this field if you created the embedding with
+  /// [CreateEmbeddingRequest.encodingFormat] set to
+  /// [EmbeddingEncodingFormat.float].
+  List<double> get embeddingVector {
+    return embedding.mapOrNull(
+      string: (final s) => throw ArgumentError(
+        '`encodingFormat` is not set to `float` in the create embedding request',
+      ),
+      arrayNumber: (final a) => a.value,
+    )!;
+  }
+
+  /// The embedding vector as a base64-encoded string.
+  ///
+  /// You can only use this field if you created the embedding with
+  /// [CreateEmbeddingRequest.encodingFormat] set to
+  /// [EmbeddingEncodingFormat.base64].
+  String get embeddingVectorBase64 {
+    return embedding.mapOrNull(
+      string: (final s) => s.value,
+      arrayNumber: (final a) => throw ArgumentError(
+        '`encodingFormat` is not set to `base64` in the create embedding request',
+      ),
+    )!;
+  }
+}

packages/openai_dart/lib/src/generated/schema/create_chat_completion_request.dart

@@ -287,8 +287,8 @@ class _ChatCompletionStopConverter
     if (data is String) {
       return ChatCompletionStop.string(data);
     }
-    if (data is List<String>) {
-      return ChatCompletionStop.arrayString(data);
+    if (data is List && data.every((item) => item is String)) {
+      return ChatCompletionStop.arrayString(data.cast());
     }
     throw Exception('Unexpected value for ChatCompletionStop: $data');
   }

packages/openai_dart/lib/src/generated/schema/create_completion_request.dart

@@ -343,14 +343,14 @@ class _CompletionPromptConverter
     if (data is String) {
       return CompletionPrompt.string(data);
     }
-    if (data is List<String>) {
-      return CompletionPrompt.arrayString(data);
+    if (data is List && data.every((item) => item is String)) {
+      return CompletionPrompt.arrayString(data.cast());
     }
-    if (data is List<int>) {
-      return CompletionPrompt.arrayInteger(data);
+    if (data is List && data.every((item) => item is int)) {
+      return CompletionPrompt.arrayInteger(data.cast());
     }
-    if (data is List<List<int>>) {
-      return CompletionPrompt.array(data);
+    if (data is List && data.every((item) => item is List<int>)) {
+      return CompletionPrompt.array(data.cast());
     }
     return CompletionPrompt.string('<|endoftext|>');
   }
@@ -401,8 +401,8 @@ class _CompletionStopConverter
     if (data is String) {
       return CompletionStop.string(data);
     }
-    if (data is List<String>) {
-      return CompletionStop.arrayString(data);
+    if (data is List && data.every((item) => item is String)) {
+      return CompletionStop.arrayString(data.cast());
     }
     throw Exception('Unexpected value for CompletionStop: $data');
   }

packages/openai_dart/lib/src/generated/schema/create_embedding_request.dart

@@ -158,14 +158,14 @@ class _EmbeddingInputConverter
     if (data is String) {
       return EmbeddingInput.string(data);
     }
-    if (data is List<String>) {
-      return EmbeddingInput.arrayString(data);
+    if (data is List && data.every((item) => item is String)) {
+      return EmbeddingInput.arrayString(data.cast());
     }
-    if (data is List<int>) {
-      return EmbeddingInput.arrayInteger(data);
+    if (data is List && data.every((item) => item is int)) {
+      return EmbeddingInput.arrayInteger(data.cast());
     }
-    if (data is List<List<int>>) {
-      return EmbeddingInput.array(data);
+    if (data is List && data.every((item) => item is List<int>)) {
+      return EmbeddingInput.array(data.cast());
     }
     throw Exception('Unexpected value for EmbeddingInput: $data');
   }

packages/openai_dart/lib/src/generated/schema/create_moderation_request.dart

@@ -148,8 +148,8 @@ class _ModerationInputConverter
     if (data is String) {
       return ModerationInput.string(data);
     }
-    if (data is List<String>) {
-      return ModerationInput.arrayString(data);
+    if (data is List && data.every((item) => item is String)) {
+      return ModerationInput.arrayString(data.cast());
     }
     throw Exception('Unexpected value for ModerationInput: $data');
   }

packages/openai_dart/lib/src/generated/schema/embedding.dart

@@ -19,7 +19,7 @@ class Embedding with _$Embedding {
     required int index,
 
     /// The embedding vector, which is a list of floats. The length of vector depends on the model as listed in the [embedding guide](https://platform.openai.com/docs/guides/embeddings).
-    required List<double> embedding,
+    @_EmbeddingVectorConverter() required EmbeddingVector embedding,
 
     /// The object type, which is always "embedding".
     required String object,
@@ -46,3 +46,50 @@ class Embedding with _$Embedding {
     };
   }
 }
+
+// ==========================================
+// CLASS: EmbeddingVector
+// ==========================================
+
+/// The embedding vector, which is a list of floats. The length of vector depends on the model as listed in the [embedding guide](https://platform.openai.com/docs/guides/embeddings).
+@freezed
+sealed class EmbeddingVector with _$EmbeddingVector {
+  const EmbeddingVector._();
+
+  const factory EmbeddingVector.string(
+    String value,
+  ) = _UnionEmbeddingVectorString;
+
+  const factory EmbeddingVector.arrayNumber(
+    List<double> value,
+  ) = _UnionEmbeddingVectorArrayNumber;
+
+  /// Object construction from a JSON representation
+  factory EmbeddingVector.fromJson(Map<String, dynamic> json) =>
+      _$EmbeddingVectorFromJson(json);
+}
+
+/// Custom JSON converter for [EmbeddingVector]
+class _EmbeddingVectorConverter
+    implements JsonConverter<EmbeddingVector, Object?> {
+  const _EmbeddingVectorConverter();
+
+  @override
+  EmbeddingVector fromJson(Object? data) {
+    if (data is String) {
+      return EmbeddingVector.string(data);
+    }
+    if (data is List && data.every((item) => item is double)) {
+      return EmbeddingVector.arrayNumber(data.cast());
+    }
+    throw Exception('Unexpected value for EmbeddingVector: $data');
+  }
+
+  @override
+  Object? toJson(EmbeddingVector data) {
+    return switch (data) {
+      _UnionEmbeddingVectorString(value: final v) => v,
+      _UnionEmbeddingVectorArrayNumber(value: final v) => v,
+    };
+  }
+}