Merge pull request #42 from srcnalt/feature/response-streaming

Support for text stream responses.

Author: srcnalt

README.md

@@ -66,6 +66,30 @@ private async void SendRequest()
 }
 ```
 
+To make a stream request, you can use the `CreateCompletionAsync` and `CreateChatCompletionAsync` methods. 
+These methods are going to set `Stream` property of the request to `true` and return responses through an onResponse callback.
+In this case text responses are stored in `Delta` property of the `Choices` field.
+
+```csharp
+var req = new CreateCompletionRequest{
+    Model = "text-davinci-003",
+    Prompt = "Say this is a test.",
+    MaxTokens = 7,
+    Temperature = 0
+};
+    
+openai.CreateCompletionAsync(req, 
+    (responses) => {
+        var result = string.Join("", responses.Select(response => response.Choices[0].Delta.Content));
+        Debug.Log(result);
+    }, 
+    () => {
+        Debug.Log("completed");
+    }, 
+    new CancellationTokenSource());
+}
+```
+
 ### Sample Projects
 This package includes two sample scenes that you can import via the Package Manager:
 

Runtime/DataTypes.cs

@@ -83,8 +83,8 @@ public sealed class CreateChatCompletionRequest
         public string Model { get; set; }
         public List<ChatMessage> Messages { get; set; }
         public float? Temperature { get; set; } = 1;
-        public int? N { get; set; } = 1;
-        public bool? Stream { get; set; } = false;
+        public int N { get; set; } = 1;
+        public bool Stream { get; set; } = false;
         public string Stop { get; set; }
         public int? MaxTokens { get; set; }
         public float? PresencePenalty { get; set; } = 0;
@@ -107,6 +107,7 @@ public struct CreateChatCompletionResponse : IResponse
     public struct ChatChoice
     {
         public ChatMessage Message { get; set; }
+        public ChatMessage Delta { get; set; }
         public int? Index { get; set; }
         public string FinishReason { get; set; }
     }
@@ -116,6 +117,7 @@ public struct ChatMessage
         public string Role { get; set; }
         public string Content { get; set; }
     }
+    
     #endregion
 
     #region Audio Transcriptions Data Types
@@ -159,8 +161,8 @@ public sealed class CreateCompletionRequest
         public int? MaxTokens { get; set; } = 16;
         public float? Temperature { get; set; } = 1;
         public float? TopP { get; set; } = 1;
-        public int? N { get; set; } = 1;
-        public bool? Stream { get; set; } = false;
+        public int N { get; set; } = 1;
+        public bool Stream { get; set; } = false;
         public int? Logpropbs { get; set; }
         public bool? Echo { get; set; } = false;
         public string Stop { get; set; }

Runtime/OpenAIApi.cs

@@ -1,12 +1,15 @@
+using System;
+using System.IO;
 using UnityEngine;
 using System.Text;
 using Newtonsoft.Json;
+using System.Threading;
 using System.Globalization;
 using System.Threading.Tasks;
 using UnityEngine.Networking;
 using System.Collections.Generic;
-using System.IO;
 using Newtonsoft.Json.Serialization;
+using System.Linq;
 
 namespace OpenAI
 {
@@ -87,6 +90,61 @@ private async Task<T> DispatchRequest<T>(string path, string method, byte[] payl
 
             return data;
         }
+        
+        /// <summary>
+        ///     Dispatches an HTTP request to the specified path with the specified method and optional payload.
+        /// </summary>
+        /// <param name="path">The path to send the request to.</param>
+        /// <param name="method">The HTTP method to use for the request.</param>
+        /// <param name="onResponse">A callback function to be called when a response is updated.</param>
+        /// <param name="onComplete">A callback function to be called when the request is complete.</param>
+        /// <param name="token">A cancellation token to cancel the request.</param>
+        /// <param name="payload">An optional byte array of json payload to include in the request.</param>
+        private async void DispatchRequest<T>(string path, string method, Action<List<T>> onResponse, Action onComplete, CancellationTokenSource token, byte[] payload = null) where T: IResponse
+        {
+            using (var request = UnityWebRequest.Put(path, payload))
+            {
+                request.method = method;
+                request.SetHeaders(Configuration, ContentType.ApplicationJson);
+                
+                var asyncOperation = request.SendWebRequest();
+
+                do
+                {
+                    List<T> dataList = new List<T>();
+                    string[] lines = request.downloadHandler.text.Split('\n').Where(line => line != "").ToArray();
+
+                    foreach (string line in lines)
+                    {
+                        var value = line.Replace("data: ", "");
+                        
+                        if (value.Contains("[DONE]")) 
+                        {
+                            onComplete?.Invoke();
+                            break;
+                        }
+                        
+                        var data = JsonConvert.DeserializeObject<T>(value, jsonSerializerSettings);
+
+                        if (data?.Error != null)
+                        {
+                            ApiError error = data.Error;
+                            Debug.LogError($"Error Message: {error.Message}\nError Type: {error.Type}\n");
+                        }
+                        else
+                        {
+                            dataList.Add(data);
+                        }
+                    }
+                    onResponse?.Invoke(dataList);
+                    
+                    await Task.Yield();
+                }
+                while (!asyncOperation.isDone && !token.IsCancellationRequested);
+                
+                onComplete?.Invoke();
+            }
+        }
 
         /// <summary>
         ///     Dispatches an HTTP request to the specified path with a multi-part data form.
@@ -167,6 +225,22 @@ public async Task<CreateCompletionResponse> CreateCompletion(CreateCompletionReq
             return await DispatchRequest<CreateCompletionResponse>(path, UnityWebRequest.kHttpVerbPOST, payload);
         }
 
+        /// <summary>
+        ///     Creates a chat completion request as in ChatGPT.
+        /// </summary>
+        /// <param name="request">See <see cref="CreateChatCompletionRequest"/></param>
+        /// <param name="onResponse">Callback function that will be called when stream response is updated.</param>
+        /// <param name="onComplete">Callback function that will be called when stream response is completed.</param>
+        /// <param name="token">Cancellation token to cancel the request.</param>
+        public void CreateCompletionAsync(CreateCompletionRequest request, Action<List<CreateCompletionResponse>> onResponse, Action onComplete, CancellationTokenSource token)
+        {
+            request.Stream = true;
+            var path = $"{BASE_PATH}/completions";
+            var payload = CreatePayload(request);
+            
+            DispatchRequest(path, UnityWebRequest.kHttpVerbPOST, onResponse, onComplete, token, payload);
+        }
+        
         /// <summary>
         ///     Creates a chat completion request as in ChatGPT.
         /// </summary>
@@ -176,9 +250,26 @@ public async Task<CreateChatCompletionResponse> CreateChatCompletion(CreateChatC
         {
             var path = $"{BASE_PATH}/chat/completions";
             var payload = CreatePayload(request);
+            
             return await DispatchRequest<CreateChatCompletionResponse>(path, UnityWebRequest.kHttpVerbPOST, payload);
         }
 
+        /// <summary>
+        ///     Creates a chat completion request as in ChatGPT.
+        /// </summary>
+        /// <param name="request">See <see cref="CreateChatCompletionRequest"/></param>
+        /// <param name="onResponse">Callback function that will be called when stream response is updated.</param>
+        /// <param name="onComplete">Callback function that will be called when stream response is completed.</param>
+        /// <param name="token">Cancellation token to cancel the request.</param>
+        public void CreateChatCompletionAsync(CreateChatCompletionRequest request, Action<List<CreateChatCompletionResponse>> onResponse, Action onComplete, CancellationTokenSource token)
+        {
+            request.Stream = true;
+            var path = $"{BASE_PATH}/chat/completions";
+            var payload = CreatePayload(request);
+            
+            DispatchRequest(path, UnityWebRequest.kHttpVerbPOST, onResponse, onComplete, token, payload);
+        }
+        
         /// <summary>
         ///     Creates a new edit for the provided input, instruction, and parameters.
         /// </summary>