From 8e4586a471f497981eac09dbc5a4e2dc5809049f Mon Sep 17 00:00:00 2001
From: sixwaaaay <lw.2675@qq.com>
Date: Wed, 9 Oct 2024 22:58:30 +0800
Subject: [PATCH] feat: add semantic similar search

---
 sharp/content.Tests/DomainTest.cs            | 21 ++++---
 sharp/content.Tests/repository/ClientTest.cs | 44 +++++++++++++-
 sharp/content/Program.cs                     |  3 +
 sharp/content/appsettings.json               | 10 ++--
 sharp/content/domainservice/DomainService.cs |  7 ++-
 sharp/content/endpoints/Endpoints.cs         |  4 ++
 sharp/content/repository/Client.cs           | 60 ++++++++++++++++----
 sharp/content/repository/Content.cs          | 48 +++++-----------
 8 files changed, 137 insertions(+), 60 deletions(-)

diff --git a/sharp/content.Tests/DomainTest.cs b/sharp/content.Tests/DomainTest.cs
index adddb289..3c6582ef 100644
--- a/sharp/content.Tests/DomainTest.cs
+++ b/sharp/content.Tests/DomainTest.cs
@@ -29,12 +29,13 @@ public async Task FindById_ReturnsVideoDto_WhenVideoExists()
         var mockVideoRepo = new Mock<IVideoRepository>();
         var mockUserRepo = new Mock<IUserRepository>();
         var mockVoteRepo = new Mock<IVoteRepository>();
+        var mockSearchClient = new Mock<SearchClient>(null);
         var video = new Video { Id = 1, UserId = 1 };
         var user = new User { Id = "1" };
         mockVideoRepo.Setup(repo => repo.FindById(1)).ReturnsAsync(video);
         mockUserRepo.Setup(repo => repo.FindById(1)).ReturnsAsync(user);
         mockVoteRepo.Setup(repo => repo.VotedOfVideos(It.IsAny<List<long>>())).ReturnsAsync([1]);
-        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object);
+        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object, mockSearchClient.Object);
 
         // Act
         var result = await service.FindById(1);
@@ -54,12 +55,13 @@ public async Task FindAllByIds_ReturnsVideoDtos_WhenVideosExist()
         var mockVideoRepo = new Mock<IVideoRepository>();
         var mockUserRepo = new Mock<IUserRepository>();
         var mockVoteRepo = new Mock<IVoteRepository>();
+        var mockSearchClient = new Mock<SearchClient>(null);
         var videos = new List<Video> { new() { Id = 1, UserId = 1 }, new() { Id = 2, UserId = 2 } };
         var users = new List<User> { new() { Id = "1" }, new() { Id = "2" } };
         mockVideoRepo.Setup(repo => repo.FindAllByIds(It.IsAny<IReadOnlyList<long>>())).ReturnsAsync(videos);
         mockUserRepo.Setup(repo => repo.FindAllByIds(It.IsAny<IEnumerable<long>>())).ReturnsAsync(users);
         mockVoteRepo.Setup(repo => repo.VotedOfVideos(It.IsAny<List<long>>())).ReturnsAsync([]);
-        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object);
+        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object, mockSearchClient.Object);
 
         // Act
         var result = await service.FindAllByIds([1, 2]);
@@ -76,10 +78,11 @@ public async Task Save_ReturnsSavedVideoDto_WhenVideoIsSaved()
         var mockVideoRepo = new Mock<IVideoRepository>();
         var mockUserRepo = new Mock<IUserRepository>();
         var mockVoteRepo = new Mock<IVoteRepository>();
+        var mockSearchClient = new Mock<SearchClient>(null);
         var video = new Video { Id = 1, UserId = 1 };
         var user = new User { Id = "1" };
         mockVideoRepo.Setup(repo => repo.Save(It.IsAny<Video>())).ReturnsAsync(video);
-        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object);
+        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object, mockSearchClient.Object);
 
         // Act
         await service.Save(new Video());
@@ -93,13 +96,14 @@ public async Task FindByUserId_ReturnsExpectedVideos()
         var mockVideoRepo = new Mock<IVideoRepository>();
         var mockUserRepo = new Mock<IUserRepository>();
         var mockVoteRepo = new Mock<IVoteRepository>();
+        var mockSearchClient = new Mock<SearchClient>(null);
         var videos = new List<Video> { new() { Id = 1, UserId = 1 }, new() { Id = 2, UserId = 1 } };
         var user = new User { Id = "1" };
         var voteVideoIds = new List<long> { 1, 2 };
         mockVideoRepo.Setup(repo => repo.FindByUserId(1, 1, 2)).ReturnsAsync(videos);
         mockUserRepo.Setup(repo => repo.FindById(1)).ReturnsAsync(user);
         mockVoteRepo.Setup(repo => repo.VotedOfVideos(It.IsAny<List<long>>())).ReturnsAsync(voteVideoIds);
-        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object);
+        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object, mockSearchClient.Object);
 
         // Act
         var result = await service.FindByUserId(1, 1, 2);
@@ -116,6 +120,7 @@ public async Task FindRecent_ReturnsExpectedVideos()
         var mockVideoRepo = new Mock<IVideoRepository>();
         var mockUserRepo = new Mock<IUserRepository>();
         var mockVoteRepo = new Mock<IVoteRepository>();
+        var mockSearchClient = new Mock<SearchClient>(null);
         var videos = new List<Video> { new() { Id = 1, UserId = 1 }, new() { Id = 2, UserId = 2 } };
         var users = new List<User> { new() { Id = "1" }, new() { Id = "2" } };
         var voteVideoIds = new List<long> { 1 };
@@ -123,7 +128,7 @@ public async Task FindRecent_ReturnsExpectedVideos()
         mockVideoRepo.Setup(repo => repo.FindRecent(1, 2)).ReturnsAsync(videos);
         mockUserRepo.Setup(repo => repo.FindAllByIds(It.IsAny<IEnumerable<long>>())).ReturnsAsync(users);
         mockVoteRepo.Setup(repo => repo.VotedOfVideos(It.IsAny<List<long>>())).ReturnsAsync(voteVideoIds);
-        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object);
+        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object, mockSearchClient.Object);
         // Act
         var result = await service.FindRecent(1, 2);
 
@@ -139,6 +144,7 @@ public async Task DailyPopularVideos_ReturnsExpectedVideos()
         var mockVideoRepo = new Mock<IVideoRepository>();
         var mockUserRepo = new Mock<IUserRepository>();
         var mockVoteRepo = new Mock<IVoteRepository>();
+        var mockSearchClient = new Mock<SearchClient>(null);
         var videos = new List<Video> { new() { Id = 1, UserId = 1 }, new() { Id = 2, UserId = 2 } };
         var users = new List<User> { new() { Id = "1" }, new() { Id = "2" } };
         var voteVideoIds = new List<long> { 1 };
@@ -146,7 +152,7 @@ public async Task DailyPopularVideos_ReturnsExpectedVideos()
         mockVoteRepo.Setup(repo => repo.VotedOfVideos(It.IsAny<List<long>>())).ReturnsAsync(voteVideoIds);
         mockVideoRepo.Setup(repo => repo.FindAllByIds(It.IsAny<long[]>())).ReturnsAsync(videos);
         mockUserRepo.Setup(repo => repo.FindAllByIds(It.IsAny<IEnumerable<long>>())).ReturnsAsync(users);
-        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object);
+        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object, mockSearchClient.Object);
 
         // Act
         var result = await service.DailyPopularVideos(1, 2);
@@ -164,6 +170,7 @@ public async Task VotedVideos_ReturnsExpectedVideos()
         var mockVideoRepo = new Mock<IVideoRepository>();
         var mockUserRepo = new Mock<IUserRepository>();
         var mockVoteRepo = new Mock<IVoteRepository>();
+        var mockSearchClient = new Mock<SearchClient>(null);
         var videoIds = new long[] { 1, 2 };
         var videos = new List<Video> { new() { Id = 1, UserId = 1 }, new() { Id = 2, UserId = 2 } };
         var users = new List<User> { new() { Id = "1" }, new() { Id = "2" } };
@@ -172,7 +179,7 @@ public async Task VotedVideos_ReturnsExpectedVideos()
         mockVoteRepo.Setup(repo => repo.VotedOfVideos(It.IsAny<List<long>>())).ReturnsAsync(voteVideoIds);
         mockVideoRepo.Setup(repo => repo.FindAllByIds(It.IsAny<long[]>())).ReturnsAsync(videos);
         mockUserRepo.Setup(repo => repo.FindAllByIds(It.IsAny<IEnumerable<long>>())).ReturnsAsync(users);
-        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object);
+        var service = new DomainService(mockVideoRepo.Object, mockUserRepo.Object, mockVoteRepo.Object, mockSearchClient.Object);
 
         // Act
         var result = await service.VotedVideos(1, 1, 2);
diff --git a/sharp/content.Tests/repository/ClientTest.cs b/sharp/content.Tests/repository/ClientTest.cs
index e227c981..41e32158 100644
--- a/sharp/content.Tests/repository/ClientTest.cs
+++ b/sharp/content.Tests/repository/ClientTest.cs
@@ -162,6 +162,48 @@ public async Task VotedVideos_ThrowsException_WhenResponseIsNotSuccessful()
         // Act & Assert
         await Assert.ThrowsAsync<HttpRequestException>(() => voteRepository.VotedVideos(page, size));
     }
+
+    [Fact]
+    public async Task SimilarSearch_ReturnsListOfVideoIds()
+    {
+        // Arrange
+        var videoId = 1;
+        var expectedResponse = new Response()
+        {
+            Hits = [
+                new SimilarVideo(2), new SimilarVideo(3) 
+            ]
+        };
+
+        var mockHttpMessageHandler = new Mock<HttpMessageHandler>();
+        var mockFactory = new Mock<IHttpClientFactory>();
+        var client = new HttpClient(mockHttpMessageHandler.Object)
+        {
+            BaseAddress = new Uri("http://localhost:5151")
+        };
+        mockFactory.Setup(_ => _.CreateClient("Search")).Returns(client);
+
+        var searchClient = new SearchClient(mockFactory.Object);
+
+        mockHttpMessageHandler.Protected()
+            .Setup<Task<HttpResponseMessage>>(
+                "SendAsync",
+                ItExpr.IsAny<HttpRequestMessage>(),
+                ItExpr.IsAny<CancellationToken>()
+            )
+            .ReturnsAsync(new HttpResponseMessage
+            {
+                StatusCode = HttpStatusCode.OK,
+                Content = JsonContent.Create(expectedResponse, SearchContext.Default.Response)
+            });
+        
+        // Act
+        var result = await searchClient.SimilarSearch(videoId);
+
+        // Assert
+        Assert.Equal(expectedResponse.Hits.Select(h => h.Id).ToList(), result);
+
+    }
 }
 
 
@@ -173,4 +215,4 @@ public record ScanResp(long? NextToken, List<long> TargetIds);
 [JsonSerializable(typeof(List<long>))]
 [JsonSerializable(typeof(ScanResp))]
 [JsonSerializable(typeof(InQuery))]
-partial class VoteJsonContext: JsonSerializerContext;
\ No newline at end of file
+partial class VoteJsonContext : JsonSerializerContext;
\ No newline at end of file
diff --git a/sharp/content/Program.cs b/sharp/content/Program.cs
index 36f311a9..928cdd53 100644
--- a/sharp/content/Program.cs
+++ b/sharp/content/Program.cs
@@ -86,6 +86,9 @@
 
 builder.Services.AddVoteRepository(builder.Configuration.GetConnectionString("Vote") ?? throw new InvalidOperationException("Vote connection string is null"));
 
+builder.Services.AddSearchClient(builder.Configuration.GetConnectionString("Search") ?? throw new InvalidOperationException("Search connection string is null"),
+    builder.Configuration["Token"] ?? throw new InvalidOperationException("Token is null"));
+
 builder.Services.AddDomainService().AddMessageDomain();
 
 var app = builder.Build();
diff --git a/sharp/content/appsettings.json b/sharp/content/appsettings.json
index a595d627..342f949a 100644
--- a/sharp/content/appsettings.json
+++ b/sharp/content/appsettings.json
@@ -7,9 +7,11 @@
   },
   "AllowedHosts": "*",
   "ConnectionStrings": {
-    "Default" : "Server=db; User ID=name; Password=passwd; Database=db;",
+    "Default": "Server=db; User ID=name; Password=passwd; Database=db;",
     "User": "http://user:8080",
-    "Vote": "http://graph:8088"
+    "Vote": "http://graph:8088",
+    "Search": "http://localhost:7700"
   },
-  "Secret": "secret"
-}
+  "Secret": "secret",
+  "Token": "this is a token for search"
+}
\ No newline at end of file
diff --git a/sharp/content/domainservice/DomainService.cs b/sharp/content/domainservice/DomainService.cs
index 88a5b55e..6786b607 100644
--- a/sharp/content/domainservice/DomainService.cs
+++ b/sharp/content/domainservice/DomainService.cs
@@ -33,17 +33,18 @@ public interface IDomainService
     Task<Pagination<VideoDto>> FindRecent(long page, int size);
     Task<Pagination<VideoDto>> VotedVideos(long userId, long page, int size);
     Task<Pagination<VideoDto>> DailyPopularVideos(long page, int size);
+    Task<IReadOnlyList<VideoDto>> FindSimilarVideos(long videoId);
     Task Save(Video video);
 }
 
-public class DomainService(IVideoRepository videoRepo, IUserRepository userRepo, IVoteRepository voteRepo)
+public class DomainService(IVideoRepository videoRepo, IUserRepository userRepo, IVoteRepository voteRepo, SearchClient searchClient)
     : IDomainService
 {
     public async Task<VideoDto> FindById(long id)
     {
         var video = await videoRepo.FindById(id);
         var videoToVideoDto = video.ToDto();
-        var (UserTask, VoteTask) = ( userRepo.FindById(video.UserId), voteRepo.VotedOfVideos([video.Id]));
+        var (UserTask, VoteTask) = (userRepo.FindById(video.UserId), voteRepo.VotedOfVideos([video.Id]));
         var user = await UserTask;
         var votedVideos = await VoteTask;
 
@@ -128,6 +129,8 @@ public async Task<Pagination<VideoDto>> DailyPopularVideos(long page, int size)
             NextPage = token.ToString()
         };
     }
+
+    public async Task<IReadOnlyList<VideoDto>> FindSimilarVideos(long videoId) => await FindAllByIds(await searchClient.SimilarSearch(videoId));
 }
 
 [Mapper]
diff --git a/sharp/content/endpoints/Endpoints.cs b/sharp/content/endpoints/Endpoints.cs
index 1e907f27..08990adc 100644
--- a/sharp/content/endpoints/Endpoints.cs
+++ b/sharp/content/endpoints/Endpoints.cs
@@ -70,6 +70,9 @@ public static Task<Pagination<VideoDto>> Likes(IDomainService service, long user
         return service.VotedVideos(userId, page ?? long.MaxValue, size ?? 10);
     }
 
+    public static Task<IReadOnlyList<VideoDto>> SimilarVideos(IDomainService service, long id) =>
+        service.FindSimilarVideos(id);
+
     public static async Task CreateVideo(IDomainService service, IProbe probe, ClaimsPrincipal user,
         VideoRequest request, VideoRequestValidator validator)
     {
@@ -123,6 +126,7 @@ public static void MapEndpoints(this IEndpointRouteBuilder endpoints)
         endpoints.MapGet("/users/{userId:long}/likes", Likes).WithName("getUserLikes");
         endpoints.MapGet("/videos", Videos).WithName("getVideos");
         endpoints.MapGet("/videos/{id:long}", FindVideoById).WithName("getVideo");
+        endpoints.MapGet("/videos/{id:long}/similar", SimilarVideos).WithName("getSimilarVideos");
         endpoints.MapPost("/videos/popular", DailyPopularVideos).WithName("getDailyPopularVideos");
         endpoints.MapPost("/videos", CreateVideo).RequireAuthorization().WithName("createVideo");
 
diff --git a/sharp/content/repository/Client.cs b/sharp/content/repository/Client.cs
index 97b7dc96..16f7144e 100644
--- a/sharp/content/repository/Client.cs
+++ b/sharp/content/repository/Client.cs
@@ -49,15 +49,11 @@ public interface IUserRepository
 {
     string? Token { get; set; }
 
-    /// <summary>
-    /// Find user information by id.
-    /// </summary>
+    /// <summary> Find user information by id. </summary>
     /// <param name="id"> User id. </param>
     /// <returns> User information. </returns>
     Task<User> FindById(long id);
-    /// <summary>
-    /// Find user information by id list.
-    /// </summary>
+    /// <summary> Find user information by id list. </summary>
     /// <param name="ids"> User id list. </param>
     /// <returns> User information list. </returns>
     Task<IReadOnlyList<User>> FindAllByIds(IEnumerable<long> ids);
@@ -109,17 +105,13 @@ public interface IVoteRepository
 {
     string? Token { get; set; }
 
-    /// <summary>
-    /// Get voted status of videos.
-    /// </summary>
+    /// <summary> Get voted status of videos. </summary>
     /// <param name="videoIds"> Video ids. </param>
     /// <returns> Voted status of videos. </returns>
     Task<IReadOnlyList<long>> VotedOfVideos(List<long> videoIds);
 
 
-    /// <summary>
-    /// Scan voted videos, which means paging through all voted videos.
-    /// </summary>
+    /// <summary> Scan voted videos, which means paging through all voted videos. </summary>
     /// <param name="userId"> User id. </param>
     /// <param name="page"> Page token. </param>
     /// <param name="size"> Page size. </param>
@@ -184,6 +176,41 @@ public record InQuery(List<long> ObjectIds);
 [JsonSerializable(typeof(InQuery))]
 internal partial class VoteJsonContext : JsonSerializerContext;
 
+public class SearchClient(IHttpClientFactory clientFactory)
+{
+
+    public async Task<IReadOnlyList<long>> SimilarSearch(long videoId)
+    {
+        using var client = clientFactory.CreateClient("Search");
+        var body = new RequestBody(videoId, ["id"]);
+        var content = JsonContent.Create(body, SearchContext.Default.RequestBody);
+        var req = new HttpRequestMessage(HttpMethod.Post, "/indexes/videos/similar") { Content = content };
+        var resp = await client.SendAsync(req);
+        resp.EnsureSuccessStatusCode();
+
+        var result = await resp.Content.ReadFromJsonAsync(SearchContext.Default.Response) ?? new Response();
+
+        return result.Hits.Select(h => h.Id).ToList();
+    }
+
+}
+public record RequestBody(
+    [property: JsonPropertyName("id")] long Id,
+    [property: JsonPropertyName("attributesToRetrieve")] string[] AttributesToRetrieve
+);
+
+public record Response
+{
+    [JsonPropertyName("hits")]
+    public IReadOnlyList<SimilarVideo> Hits { get; init; } = [];
+}
+
+public record SimilarVideo([property: JsonPropertyName("id")] long Id);
+
+[JsonSerializable(typeof(Response))]
+[JsonSerializable(typeof(RequestBody))]
+public partial class SearchContext : JsonSerializerContext;
+
 public static class Extension
 {
     public static IServiceCollection AddVoteRepository(this IServiceCollection services, string baseAddress)
@@ -194,6 +221,15 @@ public static IServiceCollection AddVoteRepository(this IServiceCollection servi
         return services;
     }
 
+    public static IServiceCollection AddSearchClient(this IServiceCollection services, string baseAddress, string token)
+    {
+        services.AddScoped<SearchClient>().AddHttpClient("Search", client => {
+            client.BaseAddress = new Uri(baseAddress.TrimEnd('/'));
+            client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
+        });
+        return services;
+    }
+
     public static IServiceCollection AddUserRepository(this IServiceCollection services) =>
         services.AddScoped<IUserRepository, UserRepository>();
 
diff --git a/sharp/content/repository/Content.cs b/sharp/content/repository/Content.cs
index 17796f88..db70bca6 100644
--- a/sharp/content/repository/Content.cs
+++ b/sharp/content/repository/Content.cs
@@ -106,7 +106,9 @@ public async Task<IReadOnlyList<Video>> FindAllByIds(IReadOnlyList<long> ids)
                 Processed = result.GetInt16(11)
             });
         }
-
+        // reorder the videos by the ids
+        var mapOrder = ids.Select((id, index) => (id, index)).ToDictionary(p => p.id, p => p.index);
+        videos.Sort((a, b) => mapOrder[a.Id].CompareTo(mapOrder[b.Id]));
         return videos;
     }
 
@@ -127,9 +129,7 @@ public async Task<IReadOnlyList<Video>> FindByUserId(long userId, long page, int
         return videos.ToList();
     }
 
-    /// <summary>
-    ///    Find the recent videos.
-    /// </summary>
+    /// <summary>  Find the recent videos. </summary>
     /// <param name="page">
     /// The page number.
     /// </param>
@@ -154,14 +154,10 @@ internal class RankedVideo
         public long OrderNum { get; set; }
     };
 
-    /// <summary>
-    ///   Get the daily popular videos.
-    /// </summary>
+    /// <summary> Get the daily popular videos. </summary>
     /// <param name="page"> The page number.</param>
     /// <param name="size">  The size of the page. </param>
-    /// <returns>
-    ///  A tuple of the next page token and the list of videos.
-    /// </returns>
+    /// <returns> A tuple of the next page token and the list of videos. </returns>
     public async Task<(long, IReadOnlyList<Video>)> DailyPopularVideos(long page, int size)
     {
         IEnumerable<RankedVideo> ranks;
@@ -179,15 +175,9 @@ internal class RankedVideo
         return (nextToken, videos);
     }
 
-    /// <summary>
-    ///  Save the video.
-    /// </summary>
-    /// <param name="video">
-    /// The video to save.
-    /// </param>
-    /// <returns>
-    /// The saved video.
-    /// </returns>
+    /// <summary> Save the video. </summary>
+    /// <param name="video"> The video to save. </param>
+    /// <returns> The saved video. </returns>
     public async Task<Video> Save(Video video)
     {
         await using var connection = await dataSource.OpenConnectionAsync();
@@ -211,35 +201,25 @@ public async Task<Video> Save(Video video)
     }
 }
 
-/// <summary>
-///  The extensions for the video repository.
-/// </summary>
+/// <summary> The extensions for the video repository. </summary>
 public static class VideoRepositoryExtensions
 {
     public static IServiceCollection AddVideoRepository(this IServiceCollection services) =>
         services.AddSingleton<IVideoRepository, VideoRepository>();
 }
 
-/// <summary>
-/// Represents a SQL IN clause for a list of values of type T.
-/// </summary>
+/// <summary>  a SQL IN clause for a list of values of type T. </summary>
 /// <typeparam name="T">The type of the values in the IN clause.</typeparam>
 internal class InClause<T>(IEnumerable<T> values)
 {
-    /// <summary>
-    /// Gets the parameters for the IN clause, each with a unique name and a value.
-    /// </summary>
+    /// <summary>  the parameters for the IN clause, each with a unique name and a value. </summary>
     private IEnumerable<(string, T)> Parameters =>
         values.Select((value, index) => ($"p{index}", value));
 
-    /// <summary>
-    /// Gets the condition for the IN clause, which can be used in a SQL query.
-    /// </summary>
+    /// <summary>  the condition for the IN clause, which can be used in a SQL query. </summary>
     public string Condition => $"({string.Join(", ", Parameters.Select(p => $"@{p.Item1}"))})";
 
-    /// <summary>
-    /// Adds the parameters for the IN clause to the specified SQL command.
-    /// </summary>
+    /// <summary> Adds the parameters for the IN clause to the specified SQL command.</summary>
     /// <param name="command">The SQL command to which the parameters will be added.</param>
     /// <returns>The same SQL command, for chaining calls.</returns>
     public MySqlCommand BindParam(MySqlCommand command)