Add support for JSON array format for embedings (#571)

* added tools nuget feed

* added auto detect logic

* added a test

Author: KrzysztofCwalina

codegen/nuget.config

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<configuration>
+  <packageSources>
+    <add key="generator" value="https://pkgs.dev.azure.com/azure-sdk/public/_packaging/azure-sdk-for-net/nuget/v3/index.json" />
+  </packageSources>
+</configuration>

src/Custom/Embeddings/OpenAIEmbedding.cs

@@ -4,6 +4,7 @@
 using System.Buffers.Text;
 using System.Collections.Generic;
 using System.Runtime.InteropServices;
+using System.Text.Json;
 
 namespace OpenAI.Embeddings;
 
@@ -107,13 +108,18 @@ internal OpenAIEmbedding(int index, ReadOnlyMemory<float> vector)
     // CUSTOM: Implemented custom logic to transform from BinaryData to ReadOnlyMemory<float>.
     private static ReadOnlyMemory<float> ConvertToVectorOfFloats(BinaryData binaryData)
     {
-        ReadOnlySpan<byte> base64 = binaryData.ToMemory().Span;
+        ReadOnlySpan<byte> bytes = binaryData.ToMemory().Span;
 
         // Remove quotes around base64 string.
-        if (base64.Length < 2 || base64[0] != (byte)'"' || base64[base64.Length - 1] != (byte)'"')
+        if (bytes.Length > 2 && bytes[0] == (byte)'"' && bytes[bytes.Length - 1] == (byte)'"')
         {
-            ThrowInvalidData();
+            return ConvertFromBase64(bytes);
         }
+        return ConvertFromJsonArray(binaryData);
+    }
+
+    private static ReadOnlyMemory<float> ConvertFromBase64(ReadOnlySpan<byte> base64)
+    {
         base64 = base64.Slice(1, base64.Length - 2);
 
         // Decode base64 string to bytes.
@@ -153,7 +159,33 @@ private static ReadOnlyMemory<float> ConvertToVectorOfFloats(BinaryData binaryDa
             }
         }
 
-        static void ThrowInvalidData() =>
-            throw new FormatException("The input is not a valid Base64 string of encoded floats.");
+        static void ThrowInvalidData()
+            => throw new FormatException("The input is not a valid Base64 string of encoded floats.");
+    }
+
+    private static ReadOnlyMemory<float> ConvertFromJsonArray(BinaryData jsonArray)
+    {
+        using JsonDocument document = JsonDocument.Parse(jsonArray);
+        JsonElement array = document.RootElement;
+        if (array.ValueKind != JsonValueKind.Array)
+        {
+            throw new FormatException("The input is not a valid JSON array");
+        }
+
+        int arrayLength = array.GetArrayLength();
+        float[] vector = new float[arrayLength];
+        int index = 0;
+        try
+        {
+            foreach (JsonElement value in array.EnumerateArray())
+            {
+                vector[index++] = value.GetSingle();
+            }
+            return vector.AsMemory();
+        }
+        catch
+        {
+            throw new FormatException("The input is not a valid JSON array of float values");
+        }
     }
 }

tests/Embeddings/EmbeddingsTests.cs

@@ -3,6 +3,7 @@
 using OpenAI.Tests.Utility;
 using System;
 using System.ClientModel;
+using System.ClientModel.Primitives;
 using System.Collections.Generic;
 using System.Threading.Tasks;
 using static OpenAI.Tests.TestHelpers;
@@ -205,4 +206,34 @@ public void SerializeEmbeddingCollection()
     {
         // TODO: Add this test.
     }
+
+    [Test]
+    public void JsonArraySupport()
+    {
+        string json = """
+        {
+          "object":"list",
+          "data":[
+            {
+              "object":"embedding",
+              "embedding":[-0.011229509,0.107915245,-0.15163477]
+            }
+          ]
+        }
+        """;
+
+        BinaryData binaryData = BinaryData.FromString(json);
+
+        OpenAIEmbeddingCollection embeddings = ModelReaderWriter.Read<OpenAIEmbeddingCollection>(binaryData);
+
+        Assert.That(embeddings, Is.Not.Null);
+        Assert.That(embeddings.Count, Is.EqualTo(1));
+        var embedding = embeddings[0];
+        Assert.That(embedding, Is.Not.Null);
+        ReadOnlySpan<float> vector = embedding.ToFloats().Span;
+        Assert.That(vector.Length, Is.EqualTo(3));
+        Assert.That(vector[0], Is.EqualTo(-0.011229509f));
+        Assert.That(vector[1], Is.EqualTo(0.107915245f));
+        Assert.That(vector[2], Is.EqualTo(-0.15163477f));
+    }
 }