🎉 Add Azure Content Moderator service for image analysis

webapi/Controllers/DocumentImportController.cs

@@ -21,6 +21,7 @@
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using Microsoft.SemanticKernel;
+using Microsoft.SemanticKernel.AI;
 using Microsoft.SemanticKernel.Text;
 using UglyToad.PdfPig;
 using UglyToad.PdfPig.DocumentLayoutAnalysis.TextExtractor;
@@ -79,6 +80,7 @@ private enum SupportedFileType
     private const string GlobalDocumentUploadedClientCall = "GlobalDocumentUploaded";
     private const string ReceiveMessageClientCall = "ReceiveMessage";
     private readonly IOcrEngine _ocrEngine;
+    private readonly AzureContentSafety? _contentSafetyService = null;
 
     /// <summary>
     /// Initializes a new instance of the <see cref="DocumentImportController"/> class.
@@ -91,7 +93,8 @@ private enum SupportedFileType
         ChatMemorySourceRepository sourceRepository,
         ChatMessageRepository messageRepository,
         ChatParticipantRepository participantRepository,
-        IOcrEngine ocrEngine)
+        IOcrEngine ocrEngine,
+        AzureContentSafety? contentSafety = null)
     {
         this._logger = logger;
         this._options = documentMemoryOptions.Value;
@@ -101,6 +104,19 @@ private enum SupportedFileType
         this._messageRepository = messageRepository;
         this._participantRepository = participantRepository;
         this._ocrEngine = ocrEngine;
+        this._contentSafetyService = contentSafety;
+    }
+
+    /// <summary>
+    /// Gets the status of content safety.
+    /// </summary>
+    /// <returns></returns>
+    [HttpGet]
+    [Route("contentSafety/status")]
+    [ProducesResponseType(StatusCodes.Status200OK)]
+    public bool ContentSafetyStatus()
+    {
+        return this._contentSafetyService!.ContentSafetyStatus(this._logger);
     }
 
     /// <summary>
@@ -265,7 +281,7 @@ private async Task ValidateDocumentImportFormAsync(DocumentImportForm documentIm
                 throw new ArgumentException($"File {formFile.FileName} size exceeds the limit.");
             }
 
-            // Make sure the file type is supported.
+            // Make sure the file type is supported and validate any images if ContentSafety is enabled.
             var fileType = this.GetFileType(Path.GetFileName(formFile.FileName));
             switch (fileType)
             {
@@ -276,16 +292,41 @@ private async Task ValidateDocumentImportFormAsync(DocumentImportForm documentIm
                 case SupportedFileType.Jpg:
                 case SupportedFileType.Png:
                 case SupportedFileType.Tiff:
-                {
                     if (this._ocrSupportOptions.Type != OcrSupportOptions.OcrSupportType.None)
                     {
+                        if (documentImportForm.UseContentSafety)
+                        {
+                            if (!this._contentSafetyService!.ContentSafetyStatus(this._logger))
+                            {
+                                throw new ArgumentException("Unable to analyze image. Content Safety is currently disabled in the backend.");
+                            }
+
+                            var violations = new List<string>();
+                            try
+                            {
+                                // Convert the form file to a base64 string
+                                var base64Image = await this.ConvertFormFileToBase64Async(formFile);
+
+                                // Call the content safety controller to analyze the image
+                                var imageAnalysisResponse = await this._contentSafetyService!.ImageAnalysisAsync(base64Image, default);
+                                violations = AzureContentSafety.ParseViolatedCategories(imageAnalysisResponse, this._contentSafetyService!.Options!.ViolationThreshold);
+                            }
+                            catch (Exception ex) when (!ex.IsCriticalException())
+                            {
+                                this._logger.LogError(ex, "Failed to analyze image {0} with Content Safety. ErrorCode: {{1}}", formFile.FileName, (ex as AIException)?.ErrorCode);
+                                throw new AggregateException($"Failed to analyze image {formFile.FileName} with Content Safety.", ex);
+                            }
+
+                            if (violations.Count > 0)
+                            {
+                                throw new ArgumentException($"Unable to upload image {formFile.FileName}. Detected undesirable content with potential risk: {string.Join(", ", violations)}");
+                            }
+                        }
                         break;
                     }
-
                     throw new ArgumentException($"Unsupported image file type: {fileType} when " +
                         $"{OcrSupportOptions.PropertyName}:{nameof(OcrSupportOptions.Type)} is set to " +
                         nameof(OcrSupportOptions.OcrSupportType.None));
-                }
                 default:
                     throw new ArgumentException($"Unsupported file type: {fileType}");
             }
@@ -315,11 +356,12 @@ private async Task<ImportResult> ImportDocumentHelperAsync(IKernel kernel, IForm
             case SupportedFileType.Jpg:
             case SupportedFileType.Png:
             case SupportedFileType.Tiff:
-            {
                 documentContent = await this.ReadTextFromImageFileAsync(formFile);
+                if (documentContent.Trim().Length == 0)
+                {
+                    throw new ArgumentException($"Image {{{formFile.FileName}}} does not contain text.");
+                }
                 break;
-            }
-
             default:
                 // This should never happen. Validation should have already caught this.
                 return ImportResult.Fail();
@@ -487,6 +529,19 @@ private async Task<string> ReadTextFromImageFileAsync(IFormFile file)
         return textFromFile;
     }
 
+    /// <summary>
+    /// Helper method to convert a form file to a base64 string.
+    /// </summary>
+    /// <param name="file">An IFormFile object.</param>
+    /// <returns>A Base64 string of the content of the image.</returns>
+    private async Task<string> ConvertFormFileToBase64Async(IFormFile formFile)
+    {
+        using var memoryStream = new MemoryStream();
+        await formFile.CopyToAsync(memoryStream);
+        var bytes = memoryStream.ToArray();
+        return Convert.ToBase64String(bytes);
+    }
+
     /// <summary>
     /// Read the content of a text file.
     /// </summary>

webapi/Extensions/SemanticKernelExtensions.cs

@@ -6,9 +6,11 @@
 using System.Threading.Tasks;
 using CopilotChat.WebApi.Hubs;
 using CopilotChat.WebApi.Options;
+using CopilotChat.WebApi.Services;
 using CopilotChat.WebApi.Skills.ChatSkills;
 using CopilotChat.WebApi.Storage;
 using Microsoft.AspNetCore.SignalR;
+using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
@@ -61,6 +63,9 @@ internal static IServiceCollection AddSemanticKernelServices(this IServiceCollec
         // Semantic memory
         services.AddSemanticTextMemory();
 
+        // Azure Content Safety
+        services.AddContentSafety();
+
         // Register skills
         services.AddScoped<RegisterSkillsWithKernel>(sp => RegisterSkillsAsync);
 
@@ -103,6 +108,7 @@ public static IKernel RegisterChatSkill(this IKernel kernel, IServiceProvider sp
                 messageRelayHubContext: sp.GetRequiredService<IHubContext<MessageRelayHub>>(),
                 promptOptions: sp.GetRequiredService<IOptions<PromptsOptions>>(),
                 documentImportOptions: sp.GetRequiredService<IOptions<DocumentMemoryOptions>>(),
+                contentSafety: sp.GetService<AzureContentSafety>(),
                 planner: sp.GetRequiredService<CopilotChatPlanner>(),
                 logger: sp.GetRequiredService<ILogger<ChatSkill>>()),
             nameof(ChatSkill));
@@ -253,6 +259,20 @@ private static void AddSemanticTextMemory(this IServiceCollection services)
                 .ToTextEmbeddingsService(logger: sp.GetRequiredService<ILogger<AIServiceOptions>>())));
     }
 
+    /// <summary>
+    /// Adds Azure Content Safety
+    /// </summary>
+    internal static void AddContentSafety(this IServiceCollection services)
+    {
+        IConfiguration configuration = services.BuildServiceProvider().GetRequiredService<IConfiguration>();
+        ContentSafetyOptions options = configuration.GetSection(ContentSafetyOptions.PropertyName).Get<ContentSafetyOptions>();
+
+        if (options.Enabled)
+        {
+            services.AddSingleton<AzureContentSafety>(sp => new AzureContentSafety(new Uri(options.Endpoint), options.Key, options));
+        }
+    }
+
     /// <summary>
     /// Add the completion backend to the kernel config
     /// </summary>

webapi/Extensions/ServiceExtensions.cs

@@ -108,6 +108,12 @@ public static IServiceCollection AddOptions(this IServiceCollection services, Co
             .ValidateOnStart()
             .PostConfigure(TrimStringProperties);
 
+        // Content safety options
+        services.AddOptions<ContentSafetyOptions>()
+            .Bind(configuration.GetSection(ContentSafetyOptions.PropertyName))
+            .ValidateOnStart()
+            .PostConfigure(TrimStringProperties);
+
         return services;
     }
 

webapi/Models/Request/DocumentImportForm.cs

@@ -50,4 +50,9 @@ public enum DocumentScopes
     /// Will be used to create the chat message representing the document upload.
     /// </summary>
     public string UserName { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Flag indicating whether user has content safety enabled from the client.
+    /// </summary>
+    public bool UseContentSafety { get; set; } = false;
 }

webapi/Models/Response/ImageAnalysisResponse.cs

@@ -0,0 +1,37 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Text.Json.Serialization;
+using CopilotChat.WebApi.Services;
+
+namespace CopilotChat.WebApi.Models.Response;
+
+/// <summary>
+/// Response definition to the /contentsafety/image:analyze
+/// endpoint made by the AzureContentSafety.
+/// </summary>
+public class ImageAnalysisResponse
+{
+    /// <summary>
+    /// Gets or sets the AnalysisResult related to hate.
+    /// </summary>
+    [JsonPropertyName("hateResult")]
+    public AnalysisResult? HateResult { get; set; }
+
+    /// <summary>
+    /// Gets or sets the AnalysisResult related to self-harm.
+    /// </summary>
+    [JsonPropertyName("selfHarmResult")]
+    public AnalysisResult? SelfHarmResult { get; set; }
+
+    /// <summary>
+    /// Gets or sets the AnalysisResult related to sexual content.
+    /// </summary>
+    [JsonPropertyName("sexualResult")]
+    public AnalysisResult? SexualResult { get; set; }
+
+    /// <summary>
+    /// Gets or sets the AnalysisResult related to violence.
+    /// </summary>
+    [JsonPropertyName("violenceResult")]
+    public AnalysisResult? ViolenceResult { get; set; }
+}

webapi/Options/ContentSafetyOptions.cs

@@ -0,0 +1,38 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.ComponentModel.DataAnnotations;
+
+namespace CopilotChat.WebApi.Options;
+
+/// <summary>
+/// Configuration options for content safety.
+/// </summary>
+public class ContentSafetyOptions
+{
+    public const string PropertyName = "ContentSafety";
+
+    /// <summary>
+    /// Whether to enable content safety.
+    /// </summary>
+    [Required, NotEmptyOrWhitespace]
+    public bool Enabled { get; set; } = false;
+
+    /// <summary>
+    /// Azure Content Safety endpoints
+    /// </summary>
+    [RequiredOnPropertyValue(nameof(Enabled), true)]
+    public string Endpoint { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Key to access the content safety service.
+    /// </summary>
+    [RequiredOnPropertyValue(nameof(Enabled), true)]
+    public string Key { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Set the violation threshold. See https://learn.microsoft.com/en-us/azure/ai-services/content-safety/quickstart-image for details.
+    /// </summary>
+    [Range(0, 6)]
+    public short ViolationThreshold { get; set; } = 4;
+}