don't expose FileInfo as source via IngestionResult, as it could be S…

…tream in the future. Just expose the document id

src/Libraries/Microsoft.Extensions.DataIngestion/IngestionPipeline.cs

@@ -154,7 +154,7 @@ private async IAsyncEnumerable<IngestionResult> ProcessAsync(IEnumerable<FileInf
                     processFileActivity?.SetTag(ProcessSource.DocumentIdTagName, document.Identifier);
                     _logger?.ReadDocument(document.Identifier);
 
-                    await IngestAsync(document, processFileActivity, cancellationToken).ConfigureAwait(false);
+                    document = await IngestAsync(document, processFileActivity, cancellationToken).ConfigureAwait(false);
                 }
                 catch (Exception ex)
                 {
@@ -164,12 +164,13 @@ private async IAsyncEnumerable<IngestionResult> ProcessAsync(IEnumerable<FileInf
                     failure = ex;
                 }
 
-                yield return new IngestionResult(fileInfo, document, failure);
+                string documentId = document?.Identifier ?? fileInfo.FullName;
+                yield return new IngestionResult(documentId, document, failure);
             }
         }
     }
 
-    private async Task IngestAsync(IngestionDocument document, Activity? parentActivity, CancellationToken cancellationToken)
+    private async Task<IngestionDocument> IngestAsync(IngestionDocument document, Activity? parentActivity, CancellationToken cancellationToken)
     {
         foreach (IngestionDocumentProcessor processor in DocumentProcessors)
         {
@@ -188,5 +189,7 @@ private async Task IngestAsync(IngestionDocument document, Activity? parentActiv
         _logger?.WritingChunks(GetShortName(_writer));
         await _writer.WriteAsync(chunks, cancellationToken).ConfigureAwait(false);
         _logger?.WroteChunks(document.Identifier);
+
+        return document;
     }
 }

src/Libraries/Microsoft.Extensions.DataIngestion/IngestionResult.cs

@@ -2,7 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System;
-using System.IO;
 using Microsoft.Shared.Diagnostics;
 
 namespace Microsoft.Extensions.DataIngestion;
@@ -13,9 +12,9 @@ namespace Microsoft.Extensions.DataIngestion;
 public sealed class IngestionResult
 {
     /// <summary>
-    /// Gets the source file that was ingested.
+    /// Gets the ID of the document that was ingested.
     /// </summary>
-    public FileInfo Source { get; }
+    public string DocumentId { get; }
 
     /// <summary>
     /// Gets the ingestion document created from the source file, if reading the document has succeeded.
@@ -32,9 +31,9 @@ public sealed class IngestionResult
     /// </summary>
     public bool Succeeded => Exception is null;
 
-    internal IngestionResult(FileInfo source, IngestionDocument? document, Exception? exception)
+    internal IngestionResult(string documentId, IngestionDocument? document, Exception? exception)
     {
-        Source = Throw.IfNull(source);
+        DocumentId = Throw.IfNullOrEmpty(documentId);
         Document = document;
         Exception = exception;
     }

test/Libraries/Microsoft.Extensions.DataIngestion.Tests/IngestionPipelineTests.cs

@@ -211,7 +211,7 @@ async Task Verify(IAsyncEnumerable<IngestionResult> results)
             List<IngestionResult> ingestionResults = await results.ToListAsync();
 
             Assert.Equal(_sampleFiles.Count, ingestionResults.Count);
-            Assert.All(ingestionResults, result => Assert.NotNull(result.Source));
+            Assert.All(ingestionResults, result => Assert.NotEmpty(result.DocumentId));
             IngestionResult ingestionResult = Assert.Single(ingestionResults.Where(result => !result.Succeeded));
             Assert.IsType<ExpectedException>(ingestionResult.Exception);
             AssertErrorActivities(activities, expectedFailedActivitiesCount: 1);
@@ -246,7 +246,7 @@ private static void AssertAllIngestionsSucceeded(List<IngestionResult> ingestion
     {
         Assert.NotEmpty(ingestionResults);
         Assert.All(ingestionResults, result => Assert.True(result.Succeeded));
-        Assert.All(ingestionResults, result => Assert.NotNull(result.Source));
+        Assert.All(ingestionResults, result => Assert.NotEmpty(result.DocumentId));
         Assert.All(ingestionResults, result => Assert.NotNull(result.Document));
         Assert.All(ingestionResults, result => Assert.Null(result.Exception));
     }