SignalRServiceMock.cs

using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
using Api.Database.Models;
using Api.Services;

namespace Api.Test.Mocks
{
    public class MockSignalRService : ISignalRService
    {
        // Messages arrive on background threads -- the MQTT event handler raises them
        // while a test is polling this collection from another thread. An unguarded
        // List throws "Collection was modified; enumeration operation may not execute"
        // in the middle of a foreach, so writes take a lock and reads hand back a
        // snapshot that the caller can safely enumerate.
        private readonly List<object> _latestMessages = [];
        private readonly Lock _lock = new();

        public IReadOnlyList<object> LatestMessages
        {
            get
            {
                lock (_lock)
                {
                    return [.. _latestMessages];
                }
            }
        }

        private void Record(string label, object messageObject)
        {
            lock (_lock)
            {
                _latestMessages.Add(new { Label = label, Message = messageObject });
            }
        }

        public async Task SendMessageAsync<T>(
            string label,
            Installation? installation,
            T messageObject
        )
        {
            Record(label, messageObject!);
            await Task.CompletedTask;
        }

        public async Task SendMessageAsync<T>(
            string label,
            string? installationCode,
            T messageObject
        )
        {
            Record(label, messageObject!);
            await Task.CompletedTask;
        }

        public async Task SendMessageAsync(string label, string? installationCode, string message)
        {
            await Task.CompletedTask;
        }

        public void ReportDockFailureToSignalR(Robot robot, string message) { }

        public void ReportGeneralFailToSignalR(Robot robot, string title, string message) { }

        public void ReportAutoScheduleToSignalR(
            string type,
            string missionDefinitionId,
            string message,
            string installationCode
        ) { }
    }
}