Add Ping backend

.NET 10 solution for Ping, a Discord style chat app: Domain, Application and Infrastructure projects plus the Api host. SignalR for chat and presence, LiveKit for call tokens, EF Core on Postgres, S3 compatible storage for attachments, and OIDC auth shared with the Musify Zitadel instance. Includes the Compose stack for local development.
2026-09-21 19:32:55 +02:00
commit 0623875dfa
126 changed files with 5048 additions and 0 deletions
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+using ErrorOr;
+using Mediator;
+using Microsoft.EntityFrameworkCore;
+using Ping.Application.Contracts;
+using Ping.Application.Friends.Responses;
+using Ping.Domain.ValueObjects;
+
+namespace Ping.Application.Friends
+{
+    public record AcceptFriendRequestCommand(long CurrentUserId, Guid FriendshipId) : ICommand<ErrorOr<FriendshipResponse>>;
+
+    public class AcceptFriendRequestCommandHandler(IDatabase database, IRealtimeNotifier notifier)
+        : ICommandHandler<AcceptFriendRequestCommand, ErrorOr<FriendshipResponse>>
+    {
+        public async ValueTask<ErrorOr<FriendshipResponse>> Handle(AcceptFriendRequestCommand request, CancellationToken cancellationToken)
+        {
+            var friendship = await database.Friendships
+                .Include(f => f.Requester)
+                .Include(f => f.Addressee)
+                .FirstOrDefaultAsync(f => f.Id == request.FriendshipId, cancellationToken);
+
+            if (friendship is null)
+                return Error.NotFound(description: $"Friend request {request.FriendshipId} not found");
+
+            if (friendship.AddresseeId != request.CurrentUserId)
+                return Error.Forbidden(description: "Only the addressee can accept this friend request");
+
+            if (friendship.Status != FriendshipStatus.Pending)
+                return Error.Conflict(description: "This friend request is no longer pending");
+
+            friendship.Status = FriendshipStatus.Accepted;
+            friendship.RespondedAt = DateTime.UtcNow;
+            await database.SaveChangesAsync(cancellationToken);
+
+            await notifier.FriendshipUpdatedAsync(friendship.RequesterId, friendship.Id, cancellationToken);
+
+            return FriendshipResponse.FromEntity(friendship, request.CurrentUserId);
+        }
+    }
+}