.Net: Fix bug where filtered tag field throws. (#9804)

### Motivation and Context

#9799

### Description

Missed the mapping for enumerable strings for index creation, so needed
to add it, and a proper check for unsupported types.

### Contribution Checklist

<!-- Before submitting this PR, please make sure: -->

- [x] The code builds clean without any errors or warnings
- [x] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [x] All unit tests pass, and I have added new tests where possible
- [x] I didn't break anyone 😄

dotnet/src/Connectors/Connectors.Memory.Qdrant/QdrantVectorStoreRecordCollection.cs

@@ -175,7 +175,20 @@ await this.RunOperationAsync(
         foreach (var dataProperty in dataProperties)
         {
             var storageFieldName = this._propertyReader.GetStoragePropertyName(dataProperty.DataModelPropertyName);
-            var schemaType = QdrantVectorStoreCollectionCreateMapping.s_schemaTypeMap[dataProperty.PropertyType!];
+
+            if (QdrantVectorStoreCollectionCreateMapping.s_schemaTypeMap.TryGetValue(dataProperty.PropertyType!, out PayloadSchemaType schemaType))
+            {
+                // Do nothing since schemaType is already set.
+            }
+            else if (VectorStoreRecordPropertyVerification.IsSupportedEnumerableType(dataProperty.PropertyType) && VectorStoreRecordPropertyVerification.GetCollectionElementType(dataProperty.PropertyType) == typeof(string))
+            {
+                // For enumerable of strings, use keyword schema type, since this allows tag filtering.
+                schemaType = PayloadSchemaType.Keyword;
+            }
+            else
+            {
+                throw new InvalidOperationException($"Property {nameof(VectorStoreRecordDataProperty.IsFilterable)} on {nameof(VectorStoreRecordDataProperty)} '{dataProperty.DataModelPropertyName}' is set to true, but the property type is not supported for filtering. The Qdrant VectorStore supports filtering on {string.Join(", ", QdrantVectorStoreCollectionCreateMapping.s_schemaTypeMap.Keys.Select(x => x.Name))} properties only.");
+            }
 
             await this.RunOperationAsync(
                 "CreatePayloadIndex",

dotnet/src/IntegrationTests/Connectors/Memory/Qdrant/QdrantVectorStoreFixture.cs

@@ -57,7 +57,7 @@ public QdrantVectorStoreFixture()
                 new VectorStoreRecordDataProperty("HotelCode", typeof(int)) { IsFilterable = true },
                 new VectorStoreRecordDataProperty("ParkingIncluded", typeof(bool)) { IsFilterable = true, StoragePropertyName = "parking_is_included" },
                 new VectorStoreRecordDataProperty("HotelRating", typeof(float)) { IsFilterable = true },
-                new VectorStoreRecordDataProperty("Tags", typeof(List<string>)),
+                new VectorStoreRecordDataProperty("Tags", typeof(List<string>)) { IsFilterable = true },
                 new VectorStoreRecordDataProperty("Description", typeof(string)),
                 new VectorStoreRecordVectorProperty("DescriptionEmbedding", typeof(ReadOnlyMemory<float>?)) { Dimensions = VectorDimensions, DistanceFunction = DistanceFunction.ManhattanDistance }
             }
@@ -146,11 +146,17 @@ await this.QdrantClient.CreateCollectionAsync(
 
         // Create test data common to both named and unnamed vectors.
         var tags = new ListValue();
-        tags.Values.Add("t1");
-        tags.Values.Add("t2");
+        tags.Values.Add("t11.1");
+        tags.Values.Add("t11.2");
         var tagsValue = new Value();
         tagsValue.ListValue = tags;
 
+        var tags2 = new ListValue();
+        tags2.Values.Add("t13.1");
+        tags2.Values.Add("t13.2");
+        var tagsValue2 = new Value();
+        tagsValue2.ListValue = tags2;
+
         // Create some test data using named vectors.
         var embedding = await this.EmbeddingGenerator.GenerateEmbeddingAsync("This is a great hotel.");
         var embeddingArray = embedding.ToArray();
@@ -183,7 +189,7 @@ await this.QdrantClient.CreateCollectionAsync(
             {
                 Id = 13,
                 Vectors = new Vectors { Vectors_ = namedVectors3 },
-                Payload = { ["HotelName"] = "My Hotel 13", ["HotelCode"] = 13, ["parking_is_included"] = false, ["Description"] = "This is a great hotel." }
+                Payload = { ["HotelName"] = "My Hotel 13", ["HotelCode"] = 13, ["parking_is_included"] = false, ["Tags"] = tagsValue2, ["Description"] = "This is a great hotel." }
             },
             new PointStruct
             {
@@ -214,7 +220,7 @@ await this.QdrantClient.CreateCollectionAsync(
             {
                 Id = 13,
                 Vectors = embeddingArray,
-                Payload = { ["HotelName"] = "My Hotel 13", ["HotelCode"] = 13, ["parking_is_included"] = false, ["Description"] = "This is a great hotel." }
+                Payload = { ["HotelName"] = "My Hotel 13", ["HotelCode"] = 13, ["parking_is_included"] = false, ["Tags"] = tagsValue2, ["Description"] = "This is a great hotel." }
             },
         ];
 
@@ -327,7 +333,7 @@ public record HotelInfo()
         [VectorStoreRecordData(IsFilterable = true, StoragePropertyName = "parking_is_included")]
         public bool ParkingIncluded { get; set; }
 
-        [VectorStoreRecordData]
+        [VectorStoreRecordData(IsFilterable = true)]
         public List<string> Tags { get; set; } = new List<string>();
 
         /// <summary>A data field.</summary>

dotnet/src/IntegrationTests/Connectors/Memory/Qdrant/QdrantVectorStoreRecordCollectionTests.cs

@@ -66,7 +66,7 @@ public async Task ItCanCreateACollectionUpsertGetAndSearchAsync(bool hasNamedVec
         var vector = await fixture.EmbeddingGenerator.GenerateEmbeddingAsync("A great hotel");
         var actual = await sut.VectorizedSearchAsync(
             vector,
-            new VectorSearchOptions { Filter = new VectorSearchFilter().EqualTo("HotelCode", 30) });
+            new VectorSearchOptions { Filter = new VectorSearchFilter().EqualTo("HotelCode", 30).AnyTagEqualTo("Tags", "t2") });
 
         // Assert
         var collectionExistResult = await sut.CollectionExistsAsync();
@@ -221,8 +221,8 @@ public async Task ItCanGetDocumentFromVectorStoreAsync(bool useRecordDefinition,
         Assert.True(getResult?.ParkingIncluded);
         Assert.Equal(4.5f, getResult?.HotelRating);
         Assert.Equal(2, getResult?.Tags.Count);
-        Assert.Equal("t1", getResult?.Tags[0]);
-        Assert.Equal("t2", getResult?.Tags[1]);
+        Assert.Equal("t11.1", getResult?.Tags[0]);
+        Assert.Equal("t11.2", getResult?.Tags[1]);
         Assert.Equal("This is a great hotel.", getResult?.Description);
         if (withEmbeddings)
         {
@@ -389,7 +389,7 @@ public async Task ItCanSearchWithFilterAsync(bool useRecordDefinition, string co
 
         // Act.
         var vector = await fixture.EmbeddingGenerator.GenerateEmbeddingAsync("A great hotel");
-        var filter = filterType == "equality" ? new VectorSearchFilter().EqualTo("HotelName", "My Hotel 11") : new VectorSearchFilter().AnyTagEqualTo("Tags", "t1");
+        var filter = filterType == "equality" ? new VectorSearchFilter().EqualTo("HotelName", "My Hotel 13") : new VectorSearchFilter().AnyTagEqualTo("Tags", "t13.2");
         var actual = await sut.VectorizedSearchAsync(
             vector,
             new()
@@ -402,12 +402,11 @@ public async Task ItCanSearchWithFilterAsync(bool useRecordDefinition, string co
         Assert.Single(searchResults);
 
         var searchResultRecord = searchResults.First().Record;
-        Assert.Equal(11ul, searchResultRecord?.HotelId);
-        Assert.Equal("My Hotel 11", searchResultRecord?.HotelName);
-        Assert.Equal(11, searchResultRecord?.HotelCode);
-        Assert.Equal(4.5f, searchResultRecord?.HotelRating);
-        Assert.Equal(true, searchResultRecord?.ParkingIncluded);
-        Assert.Equal(new string[] { "t1", "t2" }, searchResultRecord?.Tags.ToArray());
+        Assert.Equal(13ul, searchResultRecord?.HotelId);
+        Assert.Equal("My Hotel 13", searchResultRecord?.HotelName);
+        Assert.Equal(13, searchResultRecord?.HotelCode);
+        Assert.Equal(false, searchResultRecord?.ParkingIncluded);
+        Assert.Equal(new string[] { "t13.1", "t13.2" }, searchResultRecord?.Tags.ToArray());
         Assert.Equal("This is a great hotel.", searchResultRecord?.Description);
     }
 
@@ -448,7 +447,7 @@ public async Task ItCanUpsertAndRetrieveUsingTheGenericMapperAsync()
         Assert.Equal(11, baseSetGetResult.Data["HotelCode"]);
         Assert.True((bool)baseSetGetResult.Data["ParkingIncluded"]!);
         Assert.Equal(4.5f, baseSetGetResult.Data["HotelRating"]);
-        Assert.Equal(new[] { "t1", "t2" }, ((List<string>)baseSetGetResult.Data["Tags"]!).ToArray());
+        Assert.Equal(new[] { "t11.1", "t11.2" }, ((List<string>)baseSetGetResult.Data["Tags"]!).ToArray());
         Assert.Equal("This is a great hotel.", baseSetGetResult.Data["Description"]);
         Assert.NotNull(baseSetGetResult.Vectors["DescriptionEmbedding"]);
         Assert.IsType<ReadOnlyMemory<float>>(baseSetGetResult.Vectors["DescriptionEmbedding"]);