Use AzureEmbedFunctionService from EmbedFunction in PrepDoc (#211)

## Purpose
<!-- Describe the intention of the changes being proposed. What problem
does it solve or functionality does it add? -->
* ...

## Does this introduce a breaking change?
<!-- Mark one with an "x". -->
```
[ ] Yes
[ ] No
```

## Pull Request Type
What kind of change does this Pull Request introduce?

<!-- Please check the one that applies to this PR using "x". -->
```
[ ] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:
```

## How to Test
*  Get the code

```
git clone [repo-address]
cd [repo-name]
git checkout [branch-name]
npm install
```

* Test the code
<!-- Add steps to run the tests suite and/or manually test -->
```
```

## What to Check
Verify that the following are valid
* ...

## Other Information
<!-- Add any other helpful information that may be needed here. -->

app/functions/EmbedFunctions/EmbedFunctions.csproj

@@ -12,6 +12,7 @@
     <PackageReference Include="Azure.AI.FormRecognizer" />
     <PackageReference Include="Azure.Search.Documents" />
     <PackageReference Include="Azure.Storage.Blobs" />
+    <PackageReference Include="Azure.AI.OpenAI" />
     <PackageReference Include="Azure.Storage.Files.Shares" />
     <PackageReference Include="Azure.Storage.Queues" />
     <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Storage" />

app/functions/EmbedFunctions/EmbeddingFunction.cs

@@ -12,7 +12,6 @@ public sealed class EmbeddingFunction(
     public Task EmbedAsync(
         [BlobTrigger(
             blobPath: "content/{name}",
-            Connection = "AzureStorageAccountEndpoint")] Stream blobStream,
-        string name,
-        BlobClient client) => embeddingAggregateService.EmbedBlobAsync(client, blobStream, blobName: name);
+            Connection = "AzureWebJobsStorage")] Stream blobStream,
+        string name) => embeddingAggregateService.EmbedBlobAsync(blobStream, blobName: name);
 }

app/functions/EmbedFunctions/Program.cs

@@ -1,5 +1,8 @@
 // Copyright (c) Microsoft. All rights reserved.
 
+using Azure.AI.OpenAI;
+using Microsoft.Extensions.DependencyInjection;
+
 var host = new HostBuilder()
     .ConfigureServices(services =>
     {
@@ -36,7 +39,7 @@ uri is not null
         services.AddSingleton<BlobContainerClient>(_ =>
         {
             var blobServiceClient = new BlobServiceClient(
-                GetUriFromEnvironment("AZURE_STORAGE_ACCOUNT_ENDPOINT"),
+                GetUriFromEnvironment("AZURE_STORAGE_BLOB_ENDPOINT"),
                 credential);
 
             return blobServiceClient.GetBlobContainerClient("corpus");
@@ -45,10 +48,22 @@ uri is not null
         services.AddSingleton<EmbedServiceFactory>();
         services.AddSingleton<EmbeddingAggregateService>();
 
-        services.AddSingleton<IEmbedService, AzureSearchEmbedService>();
-        services.AddSingleton<IEmbedService, PineconeEmbedService>();
-        services.AddSingleton<IEmbedService, QdrantEmbedService>();
-        services.AddSingleton<IEmbedService, MilvusEmbedService>();
+        services.AddSingleton<IEmbedService, AzureSearchEmbedService>(provider =>
+        {
+            var searchIndexName = Environment.GetEnvironmentVariable("AZURE_SEARCH_INDEX") ?? throw new ArgumentNullException("AZURE_SEARCH_INDEX is null");
+            var embeddingModelName = Environment.GetEnvironmentVariable("AZURE_OPENAI_EMBEDDING_DEPLOYMENT") ?? throw new ArgumentNullException("AZURE_OPENAI_EMBEDDING_DEPLOYMENT is null");
+            var openaiEndPoint = Environment.GetEnvironmentVariable("AZURE_OPENAI_ENDPOINT") ?? throw new ArgumentNullException("AZURE_OPENAI_ENDPOINT is null");
+
+            var openAIClient = new OpenAIClient(new Uri(openaiEndPoint), new DefaultAzureCredential());
+
+            var searchClient = provider.GetRequiredService<SearchClient>();
+            var searchIndexClient = provider.GetRequiredService<SearchIndexClient>();
+            var blobContainerClient = provider.GetRequiredService<BlobContainerClient>();
+            var documentClient = provider.GetRequiredService<DocumentAnalysisClient>();
+            var logger = provider.GetRequiredService<ILogger<AzureSearchEmbedService>>();
+
+            return new AzureSearchEmbedService(openAIClient, embeddingModelName, searchClient, searchIndexName, searchIndexClient, documentClient, blobContainerClient, logger);
+        });
     })
     .ConfigureFunctionsWorkerDefaults()
     .Build();

app/functions/EmbedFunctions/Services/AzureSearchEmbedService.cs

@@ -1,13 +1,20 @@
 // Copyright (c) Microsoft. All rights reserved.
 
+using Azure.AI.OpenAI;
+using Google.Protobuf.WellKnownTypes;
+using Microsoft.Extensions.Options;
+
 namespace EmbedFunctions.Services;
 
-internal sealed partial class AzureSearchEmbedService(
+public sealed partial class AzureSearchEmbedService(
+    OpenAIClient openAIClient,
+    string embeddingModelName,
     SearchClient indexSectionClient,
+    string searchIndexName,
     SearchIndexClient searchIndexClient,
     DocumentAnalysisClient documentAnalysisClient,
     BlobContainerClient corpusContainerClient,
-    ILogger<AzureSearchEmbedService> logger) : IEmbedService
+    ILogger<AzureSearchEmbedService>? logger) : IEmbedService
 {
     [GeneratedRegex("[^0-9a-zA-Z_-]")]
     private static partial Regex MatchInSetRegex();
@@ -16,9 +23,6 @@ public async Task<bool> EmbedBlobAsync(Stream blobStream, string blobName)
     {
         try
         {
-            var searchIndexName = Environment.GetEnvironmentVariable(
-                "AZURE_SEARCH_INDEX") ?? "gptkbindex";
-
             await EnsureSearchIndexAsync(searchIndexName);
 
             var pageMap = await GetDocumentTextAsync(blobStream, blobName);
@@ -41,67 +45,94 @@ public async Task<bool> EmbedBlobAsync(Stream blobStream, string blobName)
         }
         catch (Exception exception)
         {
-            logger.LogError(
+            logger?.LogError(
                 exception, "Failed to embed blob '{BlobName}'", blobName);
 
             return false;
         }
     }
 
-    private async Task EnsureSearchIndexAsync(string searchIndexName)
+    public async Task CreateSearchIndexAsync(string searchIndexName)
     {
-        var indexNames = searchIndexClient.GetIndexNamesAsync();
-        await foreach (var page in indexNames.AsPages())
+        string vectorSearchConfigName = "my-vector-config";
+        string vectorSearchProfile = "my-vector-profile";
+        var index = new SearchIndex(searchIndexName)
         {
-            if (page.Values.Any(indexName => indexName == searchIndexName))
+            VectorSearch = new()
             {
-                logger.LogWarning(
-                    "Search index '{SearchIndexName}' already exists", searchIndexName);
-                return;
+                Algorithms =
+            {
+                new HnswVectorSearchAlgorithmConfiguration(vectorSearchConfigName)
+            },
+                Profiles =
+            {
+                new VectorSearchProfile(vectorSearchProfile, vectorSearchConfigName)
             }
-        }
-
-        var index = new SearchIndex(searchIndexName)
-        {
+            },
             Fields =
+        {
+            new SimpleField("id", SearchFieldDataType.String) { IsKey = true },
+            new SearchableField("content") { AnalyzerName = LexicalAnalyzerName.EnMicrosoft },
+            new SimpleField("category", SearchFieldDataType.String) { IsFacetable = true },
+            new SimpleField("sourcepage", SearchFieldDataType.String) { IsFacetable = true },
+            new SimpleField("sourcefile", SearchFieldDataType.String) { IsFacetable = true },
+            new SearchField("embedding", SearchFieldDataType.Collection(SearchFieldDataType.Single))
             {
-                new SimpleField("id", SearchFieldDataType.String) { IsKey = true },
-                new SearchableField("content") { AnalyzerName = "en.microsoft" },
-                new SimpleField("category", SearchFieldDataType.String) { IsFacetable = true },
-                new SimpleField("sourcepage", SearchFieldDataType.String) { IsFacetable = true },
-                new SimpleField("sourcefile", SearchFieldDataType.String) { IsFacetable = true }
-            },
+                VectorSearchDimensions = 1536,
+                IsSearchable = true,
+                VectorSearchProfile = vectorSearchProfile,
+            }
+        },
             SemanticSettings = new SemanticSettings
             {
                 Configurations =
+            {
+                new SemanticConfiguration("default", new PrioritizedFields
                 {
-                    new SemanticConfiguration("default", new PrioritizedFields
+                    ContentFields =
                     {
-                        ContentFields =
+                        new SemanticField
                         {
-                            new SemanticField
-                            {
-                                FieldName = "content"
-                            }
+                            FieldName = "content"
                         }
-                    })
                     }
+                })
+            }
             }
         };
 
-        logger.LogInformation(
-            "Creating '{searchIndexName}' search index", searchIndexName);
+        logger?.LogInformation(
+                       "Creating '{searchIndexName}' search index", searchIndexName);
 
         await searchIndexClient.CreateIndexAsync(index);
     }
 
+    public async Task EnsureSearchIndexAsync(string searchIndexName)
+    {
+        var indexNames = searchIndexClient.GetIndexNamesAsync();
+        await foreach (var page in indexNames.AsPages())
+        {
+            if (page.Values.Any(indexName => indexName == searchIndexName))
+            {
+                logger?.LogWarning(
+                    "Search index '{SearchIndexName}' already exists", searchIndexName);
+                return;
+            }
+        }
+
+        await CreateSearchIndexAsync(searchIndexName);
+    }
+
     private async Task<IReadOnlyList<PageDetail>> GetDocumentTextAsync(Stream blobStream, string blobName)
     {
-        logger.LogInformation(
+        logger?.LogInformation(
             "Extracting text from '{Blob}' using Azure Form Recognizer", blobName);
 
+        using var ms = new MemoryStream();
+        blobStream.CopyTo(ms);
+        ms.Position = 0;
         AnalyzeDocumentOperation operation = documentAnalysisClient.AnalyzeDocument(
-            WaitUntil.Started, "prebuilt-layout", blobStream);
+            WaitUntil.Started, "prebuilt-layout", ms);
 
         var offset = 0;
         List<PageDetail> pageMap = [];
@@ -208,7 +239,7 @@ private async Task UploadCorpusAsync(string corpusBlobName, string text)
             return;
         }
 
-        logger.LogInformation("Uploading corpus '{CorpusBlobName}'", corpusBlobName);
+        logger?.LogInformation("Uploading corpus '{CorpusBlobName}'", corpusBlobName);
 
         await using var stream = new MemoryStream(Encoding.UTF8.GetBytes(text));
         await blobClient.UploadAsync(stream, new BlobHttpHeaders
@@ -231,7 +262,7 @@ private IEnumerable<Section> CreateSections(
         var start = 0;
         var end = length;
 
-        logger.LogInformation("Splitting '{BlobName}' into sections", blobName);
+        logger?.LogInformation("Splitting '{BlobName}' into sections", blobName);
 
         while (start + SectionOverlap < length)
         {
@@ -300,9 +331,9 @@ private IEnumerable<Section> CreateSections(
                 // If the section ends with an unclosed table, we need to start the next section with the table.
                 // If table starts inside SentenceSearchLimit, we ignore it, as that will cause an infinite loop for tables longer than MaxSectionLength
                 // If last table starts inside SectionOverlap, keep overlapping
-                if (logger.IsEnabled(LogLevel.Warning))
+                if (logger?.IsEnabled(LogLevel.Warning) is true)
                 {
-                    logger.LogWarning("""
+                    logger?.LogWarning("""
                         Section ends with unclosed table, starting next section with the
                         table at page {Offset} offset {Start} table start {LastTableStart}
                         """,
@@ -349,10 +380,10 @@ private static string BlobNameFromFilePage(string blobName, int page = 0) => Pat
 
     private async Task IndexSectionsAsync(string searchIndexName, IEnumerable<Section> sections, string blobName)
     {
-        var infoLoggingEnabled = logger.IsEnabled(LogLevel.Information);
-        if (infoLoggingEnabled)
+        var infoLoggingEnabled = logger?.IsEnabled(LogLevel.Information);
+        if (infoLoggingEnabled is true)
         {
-            logger.LogInformation("""
+            logger?.LogInformation("""
                 Indexing sections from '{BlobName}' into search index '{SearchIndexName}'
                 """,
                 blobName,
@@ -363,6 +394,8 @@ Indexing sections from '{BlobName}' into search index '{SearchIndexName}'
         var batch = new IndexDocumentsBatch<SearchDocument>();
         foreach (var section in sections)
         {
+            var embeddings = await openAIClient.GetEmbeddingsAsync(embeddingModelName, new Azure.AI.OpenAI.EmbeddingsOptions(section.Content.Replace('\r', ' ')));
+            var embedding = embeddings.Value.Data.FirstOrDefault()?.Embedding.ToArray() ?? [];
             batch.Actions.Add(new IndexDocumentsAction<SearchDocument>(
                 IndexActionType.MergeOrUpload,
                 new SearchDocument
@@ -371,7 +404,8 @@ Indexing sections from '{BlobName}' into search index '{SearchIndexName}'
                     ["content"] = section.Content,
                     ["category"] = section.Category,
                     ["sourcepage"] = section.SourcePage,
-                    ["sourcefile"] = section.SourceFile
+                    ["sourcefile"] = section.SourceFile,
+                    ["embedding"] = embedding,
                 }));
 
             iteration++;
@@ -380,9 +414,9 @@ Indexing sections from '{BlobName}' into search index '{SearchIndexName}'
                 // Every one thousand documents, batch create.
                 IndexDocumentsResult result = await indexSectionClient.IndexDocumentsAsync(batch);
                 int succeeded = result.Results.Count(r => r.Succeeded);
-                if (infoLoggingEnabled)
+                if (infoLoggingEnabled is true)
                 {
-                    logger.LogInformation("""
+                    logger?.LogInformation("""
                         Indexed {Count} sections, {Succeeded} succeeded
                         """,
                         batch.Actions.Count,
@@ -399,9 +433,9 @@ Indexing sections from '{BlobName}' into search index '{SearchIndexName}'
             var index = new SearchIndex($"index-{batch.Actions.Count}");
             IndexDocumentsResult result = await indexSectionClient.IndexDocumentsAsync(batch);
             int succeeded = result.Results.Count(r => r.Succeeded);
-            if (logger.IsEnabled(LogLevel.Information))
+            if (logger?.IsEnabled(LogLevel.Information) is true)
             {
-                logger.LogInformation("""
+                logger?.LogInformation("""
                     Indexed {Count} sections, {Succeeded} succeeded
                     """,
                 batch.Actions.Count,

app/functions/EmbedFunctions/Services/EmbeddingAggregateService.cs

@@ -1,12 +1,15 @@
 // Copyright (c) Microsoft. All rights reserved.
 
+using System.IO;
+
 namespace EmbedFunctions.Services;
 
 public sealed class EmbeddingAggregateService(
     EmbedServiceFactory embedServiceFactory,
+    BlobContainerClient client,
     ILogger<EmbeddingAggregateService> logger)
 {
-    internal async Task EmbedBlobAsync(BlobClient client, Stream blobStream, string blobName)
+    internal async Task EmbedBlobAsync(Stream blobStream, string blobName)
     {
         try
         {

app/prepdocs/PrepareDocs/PrepareDocs.csproj

@@ -18,5 +18,9 @@
     <PackageReference Include="PdfSharpCore" />
     <PackageReference Include="System.CommandLine" />
   </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\functions\EmbedFunctions\EmbedFunctions.csproj" />
+  </ItemGroup>
 
 </Project>

app/prepdocs/PrepareDocs/Program.Clients.cs

@@ -1,6 +1,9 @@
 // Copyright (c) Microsoft. All rights reserved.
 
 
+using EmbedFunctions.Services;
+using Microsoft.Extensions.Logging;
+
 internal static partial class Program
 {
     private static BlobContainerClient? s_corpusContainerClient;
@@ -16,6 +19,21 @@ internal static partial class Program
     private static readonly SemaphoreSlim s_searchIndexLock = new(1);
     private static readonly SemaphoreSlim s_searchLock = new(1);
     private static readonly SemaphoreSlim s_openAILock = new(1);
+    private static readonly SemaphoreSlim s_embeddingLock = new(1);
+
+    private static Task<AzureSearchEmbedService> GetAzureSearchEmbedService(AppOptions options) =>
+        GetLazyClientAsync<AzureSearchEmbedService>(options, s_embeddingLock, async o =>
+        {
+            var searchIndexClient = await GetSearchIndexClientAsync(o);
+            var searchClient = await GetSearchClientAsync(o);
+            var documentClient = await GetFormRecognizerClientAsync(o);
+            var blobContainerClient = await GetBlobContainerClientAsync(o);
+            var openAIClient = await GetAzureOpenAIClientAsync(o);
+            var embeddingModelName = o.EmbeddingModelName ?? throw new ArgumentNullException(nameof(o.EmbeddingModelName));
+            var searchIndexName = o.SearchIndexName ?? throw new ArgumentNullException(nameof(o.SearchIndexName));
+
+            return new AzureSearchEmbedService(openAIClient, embeddingModelName, searchClient, searchIndexName, searchIndexClient, documentClient, blobContainerClient, null);
+        });
 
     private static Task<BlobContainerClient> GetCorpusBlobContainerClientAsync(AppOptions options) =>
         GetLazyClientAsync<BlobContainerClient>(options, s_corpusContainerLock, static async o =>