Rename LinkMemories -> ConnectMemories

Support linking multiple memories in one call.

Author: mbcrawfo

src/KnowledgeBaseServer/Tools/ConnectMemoriesTool.cs

@@ -0,0 +1,64 @@
+using System;
+using System.ComponentModel;
+using System.Linq;
+using Dapper;
+using Microsoft.Data.Sqlite;
+using ModelContextProtocol.Server;
+
+namespace KnowledgeBaseServer.Tools;
+
+[McpServerToolType]
+public static class ConnectMemoriesTool
+{
+    [McpServerTool(
+        Name = "ConnectMemories",
+        ReadOnly = false,
+        Destructive = false,
+        Idempotent = true,
+        OpenWorld = false
+    )]
+    [Description("Connects memories together to help find related memories in the future.")]
+    public static string Handle(
+        ConnectionString connectionString,
+        [Description("Id of the parent memory (the older memory).")] Guid parentMemoryId,
+        [Description("Id of the child memories (the newer memories).")] Guid[] childMemories
+    )
+    {
+        var now = DateTimeOffset.UtcNow;
+        var data = childMemories
+            .Select(id => new
+            {
+                FromMemoryId = id,
+                ToMemoryId = parentMemoryId,
+                Created = now,
+            })
+            .ToArray();
+
+        using var connection = connectionString.CreateConnection();
+        using var transaction = connection.BeginTransaction();
+
+        try
+        {
+            connection.Execute(
+                sql: """
+                insert into memory_links (from_memory_id, to_memory_id, created) values
+                (@FromMemoryId, @ToMemoryId, @Created)
+                """,
+                data
+            );
+            transaction.Commit();
+        }
+        // FK constraint violation
+        catch (SqliteException ex) when (ex is { SqliteErrorCode: 19, SqliteExtendedErrorCode: 787 })
+        {
+            return "Invalid memory ids provided.";
+        }
+        // PK constraint violation
+        catch (SqliteException ex) when (ex is { SqliteErrorCode: 19, SqliteExtendedErrorCode: 1555 })
+        {
+            return "Some of the requested memories are already linked.";
+        }
+
+        return "Memories linked successfully.";
+    }
+}

src/KnowledgeBaseServer/Tools/LinkMemoriesTool.cs

@@ -0,0 +1,100 @@
+using System.Diagnostics;
+using System.Text.Json;
+using Bogus;
+using KnowledgeBaseServer.Dtos;
+using KnowledgeBaseServer.Tests.Data;
+using KnowledgeBaseServer.Tools;
+using Shouldly;
+using Xunit;
+
+namespace KnowledgeBaseServer.Tests.Tools;
+
+public class ConnectMemoriesToolTests : DatabaseTest
+{
+    private readonly Faker _faker = new();
+
+    [Fact]
+    public void ShouldReturnError_WhenIdsAreNotValid()
+    {
+        // arrange
+
+        // act
+        var result = ConnectMemoriesTool.Handle(ConnectionString, _faker.Random.Guid(), [_faker.Random.Guid()]);
+
+        // assert
+        using var connection = ConnectionString.CreateConnection();
+        result.ShouldBe("Invalid memory ids provided.");
+        connection.GetMemoryLinks().ShouldBeEmpty();
+    }
+
+    [Fact]
+    public void ShouldReturnNotModifyDatabase_WhenLinkExists()
+    {
+        // arrange
+        var memories = JsonSerializer.Deserialize<CreatedMemoryDto[]>(
+            CreateMemoriesTool.Handle(
+                ConnectionString,
+                JsonSerializerOptions.Default,
+                _faker.Lorem.Word(),
+                _faker.Lorem.Words(2)
+            )
+        );
+
+        Debug.Assert(memories is { Length: 2 });
+        var parentMemoryId = memories[0].Id;
+        var childMemoryId = memories[1].Id;
+
+        using (var seedConnection = ConnectionString.CreateConnection())
+        {
+            seedConnection.SeedMemoryLink(
+                new MemoryLink
+                {
+                    Created = _faker.Date.PastOffset(),
+                    FromMemoryId = childMemoryId,
+                    ToMemoryId = parentMemoryId,
+                }
+            );
+        }
+
+        // act
+        var result = ConnectMemoriesTool.Handle(ConnectionString, parentMemoryId, [childMemoryId]);
+
+        // assert
+        using var connection = ConnectionString.CreateConnection();
+        result.ShouldContain("already linked");
+        connection.GetMemoryLinks().ShouldHaveSingleItem();
+    }
+
+    [Fact]
+    public void ShouldCreateLink()
+    {
+        // arrange
+        var memories = JsonSerializer.Deserialize<CreatedMemoryDto[]>(
+            CreateMemoriesTool.Handle(
+                ConnectionString,
+                JsonSerializerOptions.Default,
+                _faker.Lorem.Word(),
+                _faker.Lorem.Words()
+            )
+        );
+
+        Debug.Assert(memories is { Length: 3 });
+        var parentMemoryId = memories[0].Id;
+        var child1MemoryId = memories[1].Id;
+        var child2MemoryId = memories[2].Id;
+
+        // act
+        var result = ConnectMemoriesTool.Handle(ConnectionString, parentMemoryId, [child1MemoryId, child2MemoryId]);
+
+        using var connection = ConnectionString.CreateConnection();
+        var actualMemoryLinks = connection.GetMemoryLinks();
+
+        // assert
+        result.ShouldBe("Memories linked successfully.");
+        actualMemoryLinks.ShouldSatisfyAllConditions(
+            () => actualMemoryLinks.ShouldContain(ml => ml.ToMemoryId == parentMemoryId, expectedCount: 2),
+            () => actualMemoryLinks.ShouldContain(ml => ml.FromMemoryId == child1MemoryId, expectedCount: 1),
+            () => actualMemoryLinks.ShouldContain(ml => ml.FromMemoryId == child2MemoryId, expectedCount: 1)
+        );
+    }
+}