Azure SQL Database vectorization content source

src/dotnet/Vectorization/Models/Configuration/AzureSQLDatabaseContentSourceServiceSettings.cs

@@ -0,0 +1,13 @@
+namespace FoundationaLLM.Vectorization.Models.Configuration
+{
+    /// <summary>
+    /// Provides configuration settings to initialize a Sql Database content source service.
+    /// </summary>
+    public class AzureSQLDatabaseContentSourceServiceSettings
+    {
+        /// <summary>
+        /// The connection string used for authentication.
+        /// </summary>
+        public string? ConnectionString { get; set; }
+    }
+}

src/dotnet/Vectorization/Models/Resources/ContentSourceType.cs

@@ -19,6 +19,11 @@ public enum ContentSourceType
         /// <summary>
         /// SharePoint Online document library.
         /// </summary>
-        SharePointOnline
+        SharePointOnline,
+
+        /// <summary>
+        /// Azure SQL Database.
+        /// </summary>
+        AzureSQLDatabase
     }
 }

src/dotnet/Vectorization/Services/ContentSources/AzureSQLDatabaseContentSourceService.cs

@@ -0,0 +1,87 @@
+using FoundationaLLM.Common.Constants;
+using FoundationaLLM.Vectorization.DataFormats.PDF;
+using FoundationaLLM.Vectorization.Exceptions;
+using FoundationaLLM.Vectorization.Interfaces;
+using FoundationaLLM.Vectorization.Models.Configuration;
+using Microsoft.Data.SqlClient;
+using Microsoft.Extensions.Logging;
+
+namespace FoundationaLLM.Vectorization.Services.ContentSources
+{
+    /// <summary>
+    /// Implements a vectorization content source for content residing in Azure SQL.
+    /// </summary>
+    public class AzureSQLDatabaseContentSourceService : ContentSourceServiceBase, IContentSourceService
+    {
+        private readonly ILogger<AzureSQLDatabaseContentSourceService> _logger;
+        private readonly AzureSQLDatabaseContentSourceServiceSettings _settings;
+
+        /// <summary>
+        /// Creates a new instance of the vectorization content source.
+        /// </summary>
+        public AzureSQLDatabaseContentSourceService(
+            AzureSQLDatabaseContentSourceServiceSettings settings,
+            ILoggerFactory loggerFactory)
+        {
+            _settings = settings;
+            _logger = loggerFactory.CreateLogger<AzureSQLDatabaseContentSourceService>();
+        }
+
+        /// <inheritdoc/>
+        public async Task<string> ExtractTextFromFileAsync(List<string> multipartId, CancellationToken cancellationToken)
+        {
+            ValidateMultipartId(multipartId, 5);
+
+            var binaryContent = await GetBinaryContent(
+                multipartId[0],
+                multipartId[1],
+                multipartId[2],
+                multipartId[3],
+                multipartId[4],
+                cancellationToken);
+
+            return await ExtractTextFromFileAsync(multipartId[4], binaryContent);
+        }
+
+        /// <summary>
+        /// Retrieves the binary content.
+        /// </summary>
+        /// <param name="schema">The database schema containing the target table.</param>
+        /// <param name="tableName">The name of the table from which to retrieve binary content.</param>
+        /// <param name="contentColumnName">The name of the column containing binary data.</param>
+        /// <param name="identifierColumnName">The name of the column used for identifying the specific record.</param>
+        /// <param name="identifierValue">The value identifying the specific record in the identifier column.</param>
+        /// <param name="cancellationToken">The cancellation token that signals that operations should be cancelled</param>
+        /// <returns>An object representing the binary contents.</returns>
+        private async Task<BinaryData> GetBinaryContent(string schema, string tableName, string contentColumnName, string identifierColumnName, string identifierValue, CancellationToken cancellationToken)
+        {
+            try
+            {
+                using (var connection = new SqlConnection(_settings.ConnectionString))
+                {
+                    await connection.OpenAsync(cancellationToken);
+
+                    // WARNING! This is for experimentation purposes only as it is not injection-safe!
+                    // TODO: More work to sanitize and add safety layers against injection.
+
+                    using (var command = new SqlCommand($"SELECT TOP 1 {contentColumnName} FROM [{schema}].[{tableName}] WHERE {identifierColumnName} = @identifierValue", connection))
+                    {
+                        command.Parameters.Add(new SqlParameter("@identifierValue", identifierValue));
+
+                        using (var reader = await command.ExecuteReaderAsync(cancellationToken))
+                        {
+                            if (!reader.HasRows)
+                                throw new VectorizationException($"The file {identifierValue} was not found in the database.");
+                            await reader.ReadAsync();
+                            return new BinaryData(reader[contentColumnName]);
+                        }
+                    }
+                }
+            }
+            catch (Exception ex)
+            {
+                throw new VectorizationException($"Error when extracting content from file identified by {identifierValue} in Azure SQL Database.", ex);
+            }
+        }
+    }
+}

src/dotnet/Vectorization/Services/ContentSources/ContentSourceServiceFactory.cs

@@ -41,6 +41,7 @@ public IContentSourceService GetService(string serviceName)
             {
                 ContentSourceType.AzureDataLake => CreateAzureDataLakeContentSourceService(serviceName),
                 ContentSourceType.SharePointOnline => CreateSharePointOnlineContentSourceService(serviceName),
+                ContentSourceType.AzureSQLDatabase => CreateAzureSQLDatabaseContentSourceService(serviceName),
                 _ => throw new VectorizationException($"The content source type {contentSourceProfile.Type} is not supported."),
             };
         }
@@ -55,6 +56,7 @@ public IContentSourceService GetService(string serviceName)
             {
                 ContentSourceType.AzureDataLake => (CreateAzureDataLakeContentSourceService(serviceName), contentSourceProfile),
                 ContentSourceType.SharePointOnline => (CreateSharePointOnlineContentSourceService(serviceName), contentSourceProfile),
+                ContentSourceType.AzureSQLDatabase => (CreateAzureSQLDatabaseContentSourceService(serviceName), contentSourceProfile),
                 _ => throw new VectorizationException($"The content source type {contentSourceProfile.Type} is not supported."),
             };
         }
@@ -83,5 +85,17 @@ private SharePointOnlineContentSourceService CreateSharePointOnlineContentSource
                 sharePointOnlineContentSourceServiceSettings,
                 _loggerFactory);
         }
+
+        private AzureSQLDatabaseContentSourceService CreateAzureSQLDatabaseContentSourceService(string serviceName)
+        {
+            var azureSQLDatabaseContentSourceServiceSettings = new AzureSQLDatabaseContentSourceServiceSettings();
+            _configuration.Bind(
+                $"{AppConfigurationKeySections.FoundationaLLM_Vectorization_ContentSources}:{serviceName}",
+                azureSQLDatabaseContentSourceServiceSettings);
+
+            return new AzureSQLDatabaseContentSourceService(
+                azureSQLDatabaseContentSourceServiceSettings,
+                _loggerFactory);
+        }
     }
 }

src/dotnet/Vectorization/Vectorization.csproj

@@ -15,6 +15,7 @@
     <PackageReference Include="Azure.Security.KeyVault.Secrets" Version="4.5.0" />
     <PackageReference Include="Azure.Storage.Blobs" Version="12.19.1" />
     <PackageReference Include="Azure.Storage.Queues" Version="12.17.1" />
+    <PackageReference Include="Microsoft.Data.SqlClient" Version="5.1.4" />
     <PackageReference Include="ClosedXML" Version="0.104.0-preview2" />
     <PackageReference Include="ClosedXML.Parser" Version="1.2.0" />
     <PackageReference Include="DocumentFormat.OpenXml" Version="3.0.1" />

src/dotnet/VectorizationAPI/VectorizationAPI.csproj

@@ -4,7 +4,7 @@
     <TargetFramework>net8.0</TargetFramework>
     <Nullable>enable</Nullable>
     <ImplicitUsings>enable</ImplicitUsings>
-    <InvariantGlobalization>true</InvariantGlobalization>
+    <InvariantGlobalization>false</InvariantGlobalization>
     <UserSecretsId>35b5c460-a49c-4185-a169-676d90673146</UserSecretsId>
     <AssemblyName>FoundationaLLM.Vectorization.API</AssemblyName>
     <RootNamespace>FoundationaLLM.Vectorization.API</RootNamespace>