#17 Make configuration eidtable at runtime (#18)

Reviewed-on: https://git.hobbs.zone/henry/AccessQueueService/pulls/18

AccessQueuePlayground/Components/Layout/MainLayout.razor

@@ -1,6 +1,33 @@
 @inherits LayoutComponentBase
 
-@Body
+<nav class="navbar navbar-expand-lg navbar-light bg-light mb-4">
+    <div class="container-fluid">
+        <a class="navbar-brand" href="/">AccessQueue Playground</a>
+        <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
+            <span class="navbar-toggler-icon"></span>
+        </button>
+        <div class="collapse navbar-collapse" id="navbarNav">
+            <ul class="navbar-nav">
+                <li class="nav-item">
+                    <a class="nav-link" href="/">Home</a>
+                </li>
+                <li class="nav-item">
+                    <a class="nav-link" href="/about">About</a>
+                </li>
+                <li class="nav-item">
+                    <a class="nav-link" href="/config">Config</a>
+                </li>
+                <li class="nav-item">
+                    <a class="nav-link" href="https://git.hobbs.zone/henry/AccessQueueService" target="_blank" rel="noopener">Source</a>
+                </li>
+            </ul>
+        </div>
+    </div>
+</nav>
+
+<div class="container-body">
+    @Body
+</div>
 
 <div id="blazor-error-ui">
     An unhandled error has occurred.

AccessQueuePlayground/Components/Layout/MainLayout.razor.css

@@ -16,3 +16,10 @@
         right: 0.75rem;
         top: 0.5rem;
     }
+
+.container-body {
+    width: 90%;
+    max-width: 1000px;
+    margin-left: auto;
+    margin-right: auto;
+}

AccessQueuePlayground/Components/Pages/About.razor

@@ -0,0 +1,48 @@
+@page "/about"
+
+<PageTitle>About - AccessQueue Playground</PageTitle>
+
+<h2>About AccessQueue Playground</h2>
+<p>
+    <b>AccessQueue Playground</b> is a demo Blazor application for testing and visualizing the <b>AccessQueueService</b> system. It allows you to simulate users requesting access, manage a queue, and experiment with configuration options such as expiration, activity, and capacity limits.
+</p>
+<ul>
+    <li>Project: <b>AccessQueueService</b></li>
+    <li>Frontend: <b>Blazor (BlazorBootstrap)</b></li>
+    <li>Backend: <b>.NET 8</b></li>
+</ul>
+
+<h3>How AccessQueueService Works</h3>
+<ol>
+    <li><b>Requesting Access:</b> Users are granted access if capacity is available, otherwise they are queued. Expiration and activity timeouts are enforced.</li>
+    <li><b>Queueing:</b> Users in the queue must remain active to keep their spot. The queue is managed FIFO (first-in, first-out).</li>
+    <li><b>Dequeuing:</b> When capacity is available, users are dequeued and granted access if still active.</li>
+    <li><b>Maintaining Access:</b> Users must re-request access to remain active. Expiration can be rolling or fixed.</li>
+    <li><b>Revoking Access:</b> Users can revoke their access, freeing up capacity for others.</li>
+</ol>
+
+<h3>Configuration Options</h3>
+<ul>
+    <li><b>CapacityLimit:</b> Max concurrent users with access.</li>
+    <li><b>ActivitySeconds:</b> How long a user can be inactive before losing their spot.</li>
+    <li><b>ExpirationSeconds:</b> How long before an access ticket expires.</li>
+    <li><b>RollingExpiration:</b> If true, expiration resets on activity.</li>
+    <li><b>RefreshRateMilliseconds:</b> How often the playground requests access for active users and updates the UI.</li>
+</ul>
+<p>For now these options can only be set via appsettings.json. The Playground UI does not yet support changing these values.</p>
+
+<h3>About the Playground UI</h3>
+<p>
+    The Playground UI lets you:
+    <ul>
+        <li>Add users to the queue and grant access.</li>
+        <li>Revoke access for individual users or all users.</li>
+        <li>Reset all data for testing.</li>
+        <li>See real-time updates of users with access, in queue, and inactive.</li>
+    </ul>
+</p>
+
+<h3>Source Code & Documentation</h3>
+<p>
+    See the <a href="https://git.hobbs.zone/henry/AccessQueueService" target="_blank" rel="noopener">project repository</a> for full documentation, source code, and usage instructions.
+</p>

AccessQueuePlayground/Components/Pages/Config.razor

@@ -0,0 +1,96 @@
+@page "/config"
+@inject AccessQueuePlayground.Services.IAccessQueueManager QueueManager
+@using BlazorBootstrap
+
+<h3>Access Queue Configuration</h3>
+
+<EditForm Model="config" OnValidSubmit="HandleValidSubmit">
+	<DataAnnotationsValidator />
+	<ValidationSummary />
+	<div class="mb-3">
+		<label for="capacityLimit">Capacity Limit</label>
+		<TextInput Id="capacityLimit" @bind-Value="config.CapacityLimit" Type="TextInputType.Number" />
+		@if (!isCapacityLimitValid)
+		{
+			<div class="text-danger">Please enter a positive integer.</div>
+		}
+	</div>
+	<div class="mb-3">
+		<label for="activitySeconds">Activity Seconds</label>
+		<TextInput Id="activitySeconds" @bind-Value="config.ActivitySeconds" Type="TextInputType.Number" />
+		@if (!isActivitySecondsValid)
+		{
+			<div class="text-danger">Please enter a positive integer.</div>
+		}
+	</div>
+	<div class="mb-3">
+		<label for="expirationSeconds">Expiration Seconds</label>
+		<TextInput Id="expirationSeconds" @bind-Value="config.ExpirationSeconds" Type="TextInputType.Number" />
+		@if (!isExpirationSecondsValid)
+		{
+			<div class="text-danger">Please enter a positive integer.</div>
+		}
+	</div>
+	<div class="mb-3">
+		<Switch Id="rollingExpiration" @bind-Value="config.RollingExpiration" Label="Rolling Expiration" />
+	</div>
+	<Button Type="ButtonType.Submit" Color="ButtonColor.Primary">Save</Button>
+	@if (successMessage != null)
+	{
+		<Alert Color="AlertColor.Success" Class="mt-3">@successMessage</Alert>
+	}
+</EditForm>
+
+@code {
+	private ConfigModel config = new();
+	private bool isCapacityLimitValid = true;
+	private bool isActivitySecondsValid = true;
+	private bool isExpirationSecondsValid = true;
+	private string? successMessage;
+
+	protected override void OnInitialized()
+	{
+		var current = QueueManager.GetConfig();
+		config = new ConfigModel
+			{
+				ActivitySeconds = (current.ActivitySeconds ?? 0).ToString(),
+				CapacityLimit = (current.CapacityLimit ?? 0).ToString(),
+				ExpirationSeconds = (current.ExpirationSeconds ?? 0).ToString(),
+				RollingExpiration = current.RollingExpiration ?? false
+			};
+		ValidateInputs();
+	}
+
+	private bool IsFormValid => isCapacityLimitValid && isActivitySecondsValid && isExpirationSecondsValid;
+
+	private void ValidateInputs()
+	{
+		isCapacityLimitValid = int.TryParse(config.CapacityLimit, out var cap) && cap > 0;
+		isActivitySecondsValid = int.TryParse(config.ActivitySeconds, out var act) && act > 0;
+		isExpirationSecondsValid = int.TryParse(config.ExpirationSeconds, out var exp) && exp > 0;
+	}
+
+	private async Task HandleValidSubmit()
+	{
+		successMessage = null;
+		ValidateInputs();
+		if (!IsFormValid)
+			return;
+		await Task.Run(() => QueueManager.UpdateConfig(new ()
+		{
+			ActivitySeconds = int.Parse(config.ActivitySeconds),
+			CapacityLimit = int.Parse(config.CapacityLimit),
+			ExpirationSeconds = int.Parse(config.ExpirationSeconds),
+			RollingExpiration = config.RollingExpiration
+		}));
+		successMessage = "Configuration updated successfully.";
+	}
+
+	public class ConfigModel
+	{
+		public string CapacityLimit { get; set; } = "";
+		public string ActivitySeconds { get; set; } = "";
+		public string ExpirationSeconds { get; set; } = "";
+		public bool RollingExpiration { get; set; }
+	}
+}

AccessQueuePlayground/Components/Pages/Home.razor

@@ -1,6 +1,7 @@
 @page "/"
 @using AccessQueuePlayground.Models
 @using AccessQueuePlayground.Services
+@using AccessQueueService.Models;
 @using BlazorBootstrap
 
 @inject IAccessQueueManager Manager
@@ -12,17 +13,19 @@
 	<p>
 		<b>Expiration Seconds:</b> @Config.ExpirationSeconds,
 		<b>Activity Seconds:</b> @Config.ActivitySeconds,
-		<b>Capacity Limit:</b> @Config.CapacityLimit
+		<b>Capacity Limit:</b> @Config.CapacityLimit,
+		<b>Rolling Expiration:</b> @Config.RollingExpiration
 	</p>
 }
 <p>
-	<Button Color="ButtonColor.Success" @onclick="AddUser">Add User</Button>
+	<Button Color="ButtonColor.Success" @onclick="() => AddUser(true)">Add Active User</Button>
+	<Button Color="ButtonColor.Success" Outline @onclick="() => AddUser(false)">Add Inctive User</Button>
 	<Button Color="ButtonColor.Danger" @onclick="RevokeAllAccess">Revoke All</Button>
 	<Button Color="ButtonColor.Warning" @onclick="Reset">Reset Data</Button>
 </p>
 @if (Status != null)
 {
-	<h2>Users with access</h2>
+	<h4>Users with access</h4>
 	<Grid TItem="User" Data="Status.AccessUsers" Class="table table-bordered mt-3" AllowSorting>
 		<GridColumns>
 			<GridColumn TItem="User" HeaderText="Id" PropertyName="Id" SortKeySelector="item => item.Id">
@@ -43,7 +46,7 @@
 			</GridColumn>
 		</GridColumns>
 	</Grid>
-	<h2>Users in queue</h2>
+	<h4>Users in queue</h4>
 	<Grid TItem="User" Data="Status.QueuedUsers" Class="table table-bordered mt-3">
 		<GridColumns>
 			<GridColumn TItem="User" HeaderText="Id" PropertyName="Id">
@@ -64,7 +67,7 @@
 			</GridColumn>
 		</GridColumns>
 	</Grid>
-	<h2>Inactive users</h2>
+	<h4>Inactive users</h4>
 	<Grid TItem="User" Data="Status.InactiveUsers" Class="table table-bordered mt-3" AllowSorting>
 		<GridColumns>
 			<GridColumn TItem="User" HeaderText="Id" PropertyName="Id" SortKeySelector="item => item.Id">
@@ -98,9 +101,9 @@
 		});
 	}
 
-	public void AddUser()
+	public void AddUser(bool isActive)
 	{
-		Manager.AddUser();
+		Manager.AddUser(isActive);
 		Status = Manager.GetStatus();
 	}
 

AccessQueuePlayground/Models/AccessQueueConfig.cs

@@ -1,10 +0,0 @@
-namespace AccessQueuePlayground.Models
-{
-    public class AccessQueueConfig
-    {
-        public int ActivitySeconds { get; set; }
-        public int ExpirationSeconds { get; set; }
-        public int CapacityLimit { get; set; }
-
-    }
-}

AccessQueuePlayground/Services/AccessQueueManager.cs

@@ -29,20 +29,20 @@ namespace AccessQueuePlayground.Services
 
         public AccessQueueStatus GetStatus() => _status;
 
-        public AccessQueueConfig GetConfig() => new AccessQueueConfig
+        public AccessQueueConfig GetConfig() => _accessService.GetConfiguration();
+        
+        public void UpdateConfig(AccessQueueConfig config)
         {
-            ActivitySeconds = _config.GetValue<int>("AccessQueue:ActivitySeconds"),
-            ExpirationSeconds = _config.GetValue<int>("AccessQueue:ExpirationSeconds"),
-            CapacityLimit = _config.GetValue<int>("AccessQueue:CapacityLimit")
-        };
+            _accessService.UpdateConfiguration(config);
+        }
 
-        public Guid AddUser()
+        public Guid AddUser(bool isActive)
         {
             var id = Guid.NewGuid();
             _users[id] = new User
             {
                 Id = id,
-                Active = false,
+                Active = isActive,
             };
             return id;
         }

AccessQueuePlayground/Services/IAccessQueueManager.cs

@@ -1,4 +1,5 @@
 using AccessQueuePlayground.Models;
+using AccessQueueService.Models;
 
 namespace AccessQueuePlayground.Services
 {
@@ -6,9 +7,10 @@ namespace AccessQueuePlayground.Services
     {
         public event Action? StatusUpdated;
         public AccessQueueConfig GetConfig();
+        public void UpdateConfig(AccessQueueConfig config);
         public Task RecalculateStatus();
         public AccessQueueStatus GetStatus();
-        public Guid AddUser();
+        public Guid AddUser(bool isActive);
         public void SetUserActive(Guid userId, bool isActive);
         public void RevokeAccess(Guid userId);
         public void RevokeAllAccess();

AccessQueuePlayground/appsettings.Development.json

@@ -1,8 +0,0 @@
-{
-  "Logging": {
-    "LogLevel": {
-      "Default": "Information",
-      "Microsoft.AspNetCore": "Warning"
-    }
-  }
-}

AccessQueueService/AccessQueueService.http

@@ -1,6 +0,0 @@
-@AccessQueueService_HostAddress = http://localhost:5199
-
-GET {{AccessQueueService_HostAddress}}/weatherforecast/
-Accept: application/json
-
-###

AccessQueueService/Controllers/AccessController.cs

@@ -28,5 +28,18 @@ namespace AccessQueueService.Controllers
         {
             return await _accessService.RevokeAccess(id);
         }
+
+        [HttpGet("configuration")]
+        public ActionResult<AccessQueueConfig> GetConfiguration()
+        {
+            return Ok(_accessService.GetConfiguration());
+        }
+
+        [HttpPost("configuration")]
+        public IActionResult UpdateConfiguration([FromBody] AccessQueueConfig config)
+        {
+            _accessService.PatchConfiguration(config);
+            return NoContent();
+        }
     }
 }

AccessQueueService/Models/AccessQueueConfig.cs

@@ -0,0 +1,15 @@
+namespace AccessQueueService.Models
+{
+    public class AccessQueueConfig
+    {
+        public int? CapacityLimit { get; set; }
+        public int? ActivitySeconds { get; set; }
+        public int? ExpirationSeconds { get; set; }
+        public bool? RollingExpiration { get; set; }
+
+        public AccessQueueConfig Clone()
+        {
+            return (AccessQueueConfig)this.MemberwiseClone();
+        }
+    }
+}

AccessQueueService/Services/AccessService.cs

@@ -12,37 +12,52 @@ namespace AccessQueueService.Services
         private readonly ILogger<AccessService> _logger;
 
         private readonly SemaphoreSlim _queueLock = new(1, 1);
-        private readonly int EXP_SECONDS;
-        private readonly int ACT_SECONDS;
-        private readonly int CAPACITY_LIMIT;
-        private readonly bool ROLLING_EXPIRATION;
+        private AccessQueueConfig _config;
         public AccessService(IConfiguration configuration, IAccessQueueRepo accessQueueRepo, ILogger<AccessService> logger)
         {
             _configuration = configuration;
             _accessQueueRepo = accessQueueRepo;
             _logger = logger;
-            EXP_SECONDS = _configuration.GetValue<int>("AccessQueue:ExpirationSeconds");
-            ACT_SECONDS = _configuration.GetValue<int>("AccessQueue:ActivitySeconds");
-            CAPACITY_LIMIT = _configuration.GetValue<int>("AccessQueue:CapacityLimit");
-            ROLLING_EXPIRATION = _configuration.GetValue<bool>("AccessQueue:RollingExpiration");
+            _config = new AccessQueueConfig
+            {
+                ExpirationSeconds = _configuration.GetValue<int>("AccessQueue:ExpirationSeconds"),
+                ActivitySeconds = _configuration.GetValue<int>("AccessQueue:ActivitySeconds"),
+                CapacityLimit = _configuration.GetValue<int>("AccessQueue:CapacityLimit"),
+                RollingExpiration = _configuration.GetValue<bool>("AccessQueue:RollingExpiration")
+            };
+        }
+        public AccessQueueConfig GetConfiguration() => _config.Clone();
+        public void UpdateConfiguration(AccessQueueConfig config)
+        {
+            _config = config.Clone();
+        }
+        public void PatchConfiguration(AccessQueueConfig partialConfig)
+        {
+            if (partialConfig.CapacityLimit.HasValue) _config.CapacityLimit = partialConfig.CapacityLimit.Value;
+            if (partialConfig.ActivitySeconds.HasValue) _config.ActivitySeconds = partialConfig.ActivitySeconds.Value;
+            if (partialConfig.ExpirationSeconds.HasValue) _config.ExpirationSeconds = partialConfig.ExpirationSeconds.Value;
+            if (partialConfig.RollingExpiration.HasValue) _config.RollingExpiration = partialConfig.RollingExpiration.Value;
         }
         public int UnexpiredTicketsCount => _accessQueueRepo.GetUnexpiredTicketsCount();
-        public int ActiveTicketsCount => _accessQueueRepo.GetActiveTicketsCount(DateTime.UtcNow.AddSeconds(-_configuration.GetValue<int>("AccessQueue:ActivitySeconds")));
+        public int ActiveTicketsCount => _accessQueueRepo.GetActiveTicketsCount(DateTime.UtcNow.AddSeconds(-_config.ActivitySeconds.Value));
         public int QueueCount => _accessQueueRepo.GetQueueCount();
         public async Task<AccessResponse> RequestAccess(string userId)
         {
             await _queueLock.WaitAsync();
             try
             {
-                var hasCapacity = !_accessQueueRepo.DidDequeueUntilFull(ACT_SECONDS, EXP_SECONDS, CAPACITY_LIMIT);
+                var hasCapacity = !_accessQueueRepo.DidDequeueUntilFull(
+                    _config.ActivitySeconds.Value,
+                    _config.ExpirationSeconds.Value,
+                    _config.CapacityLimit.Value);
                 var existingTicket = _accessQueueRepo.GetTicket(userId);
                 if (existingTicket != null && existingTicket.ExpiresOn > DateTime.UtcNow)
                 {
                     // Already has access
                     var expiresOn = existingTicket.ExpiresOn;
-                    if (ROLLING_EXPIRATION)
+                    if (_config.RollingExpiration.Value)
                     {
-                        expiresOn = DateTime.UtcNow.AddSeconds(EXP_SECONDS);
+                        expiresOn = DateTime.UtcNow.AddSeconds(_config.ExpirationSeconds.Value);
                     }
                     _accessQueueRepo.UpsertTicket(new AccessTicket
                     {
@@ -62,7 +77,7 @@ namespace AccessQueueService.Services
                     var accessTicket = new AccessTicket
                     {
                         UserId = userId,
-                        ExpiresOn = DateTime.UtcNow.AddSeconds(EXP_SECONDS),
+                        ExpiresOn = DateTime.UtcNow.AddSeconds(_config.ExpirationSeconds.Value),
                         LastActive = DateTime.UtcNow
                     };
                     _accessQueueRepo.UpsertTicket(accessTicket);

AccessQueueService/Services/IAccessService.cs

@@ -7,5 +7,8 @@ namespace AccessQueueService.Services
         public Task<AccessResponse> RequestAccess(string userId);
         public Task<bool> RevokeAccess(string userId);
         public Task<int> DeleteExpiredTickets();
+        public AccessQueueConfig GetConfiguration();
+        public void UpdateConfiguration(AccessQueueConfig config);
+        public void PatchConfiguration(AccessQueueConfig partialConfig);
     }
 }

AccessQueueService/appsettings.Development.json

@@ -1,8 +0,0 @@
-{
-  "Logging": {
-    "LogLevel": {
-      "Default": "Information",
-      "Microsoft.AspNetCore": "Warning"
-    }
-  }
-}

LICENSE.txt

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) [year] [fullname]
+Copyright (c) 2025 Henry Hobbs
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -1 +1,139 @@
-# AccessQueueService
+**NOTE:** I have added github as a remote but for the latest commits and issue tracking please visit https://git.hobbs.zone/henry/AccessQueueService
+
+# AccessQueueService
+
+AccessQueueService is a microservice API designed to control access to a resource with a limited number of concurrent users. It ensures fair access by:
+
+- Granting immediate access if capacity is available.
+- Placing users in a queue when the resource is full.
+- Automatically managing the queue in a first-in, first-out (FIFO) order.
+- Allowing users to revoke their access, freeing up capacity for others.
+
+This service is ideal for scenarios where you need to limit the number of users accessing a resource at the same time, such as online ticket sale platforms that control how many users can purchase tickets concurrently.
+
+Note: This service is not intended to be called directly from end-user client applications, as it could be easily bypassed. Instead, it should be integrated as middleware within your own APIs or backend services.
+
+## How the Service Works
+
+1. **Requesting Access:**
+   - When a user requests access, the service checks if the current number of active users is below `CapacityLimit`.
+   - If there is capacity, the user is granted access immediately and receives an expiration date set by `ExpirationSeconds`.
+   - If not, the user is added to a queue and receives their position in the queue.
+
+2. **Queueing:**
+   - If a user is placed in the queue, subsequent access requests will return the number of users ahead.
+   - Users must continually re-request access to remain active in the queue; inactivity may result in losing their spot.
+
+3. **Dequeuing:**
+   - Users in the queue are managed in a FIFO (first-in, first-out) order.
+   - Whenever an access request is made, if there is capacity, the service attempts to dequeue users until capacity is met.
+   - If a user is dequeued but the time since their last activity is greater than `ActivitySeconds`, they are not granted access and lose their spot in the queue.
+
+4. **Maintaining Access:**
+   - Users should continually re-request access while they are active to avoid being considered inactive.
+   - If `RollingExpiration` is enabled, the expiration is reset whenever access is re-requested.
+
+5. **Revoking Access:**
+   - If a user requests access after their expiration date, they must restart the process and re-join the queue if there isn't capacity.
+   - When a user revokes access (or their access times out), their access expires immediately.
+   
+### Note on inactivity vs expiration
+
+It is possible for the number of users with access to temporarily exceed the `CapacityLimit` if `ActivitySeconds` is less than `ExpirationSeconds`. This happens because:
+
+- The number of available slots is determined by the time since a user's last activity (`ActivitySeconds`), not by their access expiration (`ExpirationSeconds`).
+- If a user is inactive for longer than `ActivitySeconds`, they no longer count toward the capacity, allowing another user to gain access.
+- However, the original user still technically has access until their `ExpirationSeconds` elapses.
+
+**To ensure the number of users with access never exceeds `CapacityLimit`, set `ActivitySeconds` equal to `ExpirationSeconds`.**
+
+## API Routes
+
+### Request Access
+- **GET /access/{id}**
+  - **Description:** Request access for a user with the specified `id`.
+  - **Response:** Returns an `AccessResponse` object indicating whether access was granted or the user's position in the queue.
+
+### Revoke Access
+- **DELETE /access/{id}**
+  - **Description:** Revoke access for a user with the specified `id`. This will remove the user from the active list or queue and may allow the next user in the queue to gain access.
+  - **Response:** Returns a boolean indicating success.
+
+## Configuration Variables
+
+Configuration is set in `appsettings.json` or via environment variables. The main configuration section is `AccessQueue`:
+
+- **CapacityLimit**: The maximum number of users that can have access at the same time (default: 100).
+- **ActivitySeconds**: How long (in seconds) a user can remain active before being considered inactive (default: 900).
+- **ExpirationSeconds**: How long (in seconds) before an access ticket expires (default: 43200).
+- **RollingExpiration**: If true, the expiration timer resets on activity (default: true).
+- **CleanupIntervalSeconds**: How often (in seconds) the background cleanup runs to remove expired/inactive users (default: 60).
+
+Example `appsettings.json`:
+```json
+{
+  "AccessQueue": {
+    "CapacityLimit": 100,
+    "ActivitySeconds": 900,
+    "ExpirationSeconds": 43200,
+    "RollingExpiration": true,
+    "CleanupIntervalSeconds": 60
+  }
+}
+```
+
+## AccessResponse Object
+
+The `AccessResponse` object returned by the API contains the following properties:
+
+- **ExpiresOn** (`DateTime?`): The UTC timestamp when the user's access will expire. `null` if the user does not have access.
+- **RequestsAhead** (`int`): The number of requests ahead of the user in the queue. `0` if the user has access.
+- **HasAccess** (`bool`): Indicates whether the user currently has access (true if `ExpiresOn` is set and in the future).
+
+## Running the Service
+
+1. Build and run the project using .NET 8.0 or later:
+   ```powershell
+   dotnet run --project AccessQueueService/AccessQueueService.csproj
+   ```
+2. By default, the API will be available at:
+   - HTTP: http://localhost:5199
+   - HTTPS: https://localhost:7291
+   (See `AccessQueueService/Properties/launchSettings.json` for details.)
+
+## Running the Tests
+
+Unit tests for the service are located in the `AccessQueueServiceTests` project. To run all tests, use the following command from the root of the repository:
+
+```powershell
+# Run all tests in the solution
+ dotnet test
+```
+
+Test results will be displayed in the terminal. You can also use Visual Studio's Test Explorer for a graphical interface.
+
+## AccessQueuePlayground (Demo UI)
+
+The `AccessQueuePlayground` project provides a simple web-based UI for interacting with the AccessQueueService API. This is useful for testing and demonstration purposes.
+
+### Running the Playground
+
+1. Build and run the playground project:
+   ```powershell
+   dotnet run --project AccessQueuePlayground/AccessQueuePlayground.csproj
+   ```
+2. By default, the playground will be available at:
+   - HTTP: http://localhost:5108
+   - HTTPS: https://localhost:7211
+   (See `AccessQueuePlayground/Properties/launchSettings.json` for details.)
+
+### Using the Playground
+
+- Open the provided URL in your browser.
+- Use the UI to request and revoke access for different user IDs.
+- The UI will display your access status, queue position, and expiration time.
+
+This playground is intended only for local development and demonstration.
+
+## License
+See [LICENSE.txt](./LICENSE.txt) for license information.