Added to prevent reposting cart and return conflict result

State Management/daprstate/src/Post.http

@@ -1,12 +1,12 @@
 ## Post Cart Item 
 POST http://{{host-url}}/cart
 accept: application/json
-x-session-id: {{create-session-id}}
+x-session-id: {{session-id}}
 Content-Type: application/json-patch+json
 
 [
   {
-    "sku": "abc-100",
+    "sku": "abc-104",
     "quantity": 2,
     "amount": 9.99
   }

State Management/daprstate/src/ShoppingCart/Activities/Cart/Get/Get.cs

@@ -4,10 +4,9 @@
 using MediatR;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
-using ShoppingCart.Activities.Sample.Get;
 using Swashbuckle.AspNetCore.Annotations;
 
-namespace ShoppingCart.Activities.Cart
+namespace ShoppingCart.Activities.Cart.Get
 {
    [Route(Routes.Cart)]
     public class Get : BaseAsyncEndpoint.WithRequest<Query>.WithResponse<Response>

State Management/daprstate/src/ShoppingCart/Activities/Cart/Get/Handler.cs

@@ -4,8 +4,9 @@
 using MediatR;
 using ShoppingCart.Content.Activities.Cart.Post;
 using ShoppingCart.Content.Activities.Cart.Post.Models;
+using ShoppingCart.Content.Exceptions;
 
-namespace ShoppingCart.Activities.Sample.Get
+namespace ShoppingCart.Activities.Cart.Get
 {
     public class Handler : IRequestHandler<Query, Response>
     {
@@ -19,7 +20,8 @@ public Handler(IService<Item> cartStateService)
         public async Task<Response> Handle(Query request, CancellationToken cancellationToken)
         {
 
-            var items = await _cartStateService.Get(request.Session);
+            var items = await _cartStateService.Get(request.Session, cancellationToken);
+
             /// Your Logic Goes here 
             // This is only to supply an example and you should do whatever you need to achieve here
             return await Task.FromResult(new Response

State Management/daprstate/src/ShoppingCart/Activities/Cart/Get/Query.cs

@@ -1,7 +1,7 @@
 using MediatR;
 using Microsoft.AspNetCore.Mvc;
 
-namespace ShoppingCart.Activities.Sample.Get
+namespace ShoppingCart.Activities.Cart.Get
 {
     public class Query : IRequest<Response>
     {

State Management/daprstate/src/ShoppingCart/Activities/Cart/Get/Response.cs

@@ -1,7 +1,7 @@
 using System.Collections.Generic;
 using ShoppingCart.Content.Activities.Cart.Post.Models;
 
-namespace ShoppingCart.Activities.Sample.Get
+namespace ShoppingCart.Activities.Cart
 {
     public class Response
     {

State Management/daprstate/src/ShoppingCart/Activities/Cart/Get/Validator.cs

@@ -1,7 +1,13 @@
-namespace ShoppingCart.Activities.Sample.Get
+using System.Data;
+using FluentValidation;
+
+namespace ShoppingCart.Activities.Cart.Get
 {
-    public class Validator
+    public class Validator : AbstractValidator<Query>
     {
-
+        public Validator()
+        {
+            RuleFor(b => b.Session).NotNull().NotEmpty();
+        } 
     }
 }

State Management/daprstate/src/ShoppingCart/Activities/Cart/Patch/Handler.cs

@@ -17,7 +17,7 @@ public Handler(IService<Item> cartStateService)
 
         public async Task<Response> Handle(Command request, CancellationToken cancellationToken)
         {
-            var items = await _cartStateService.Update(request.Session, request.Items);
+            var items = await _cartStateService.Update(request.Session, request.Items, cancellationToken);
             return await Task.FromResult(new Response
             {
                 Items = items

State Management/daprstate/src/ShoppingCart/Activities/Cart/Post/Command.cs

@@ -8,8 +8,10 @@ namespace ShoppingCart.Content.Activities.Cart.Post
 {
     public class Command : IRequest<Response>
     {
-     [Required][FromHeader(Name = "x-session-id")] public string Session { get; set; }
+        [Required]
+        [FromHeader(Name = "x-session-id")]
+        public string Session { get; set; }
+
         [FromBody] public List<Item> Items { get; set; }
-
     }
 }

State Management/daprstate/src/ShoppingCart/Activities/Cart/Post/Handler.cs

@@ -15,8 +15,12 @@ public Handler(IService<Item> cartService)
         }
         public async Task<Response> Handle(Command request, CancellationToken cancellationToken)
         {
-            await _cartService.Save(request.Session, request.Items);
-            return new Response { Items = request.Items };
+
+            return new Response
+            {
+                Exists =  await _cartService.Save(request.Session, request.Items, cancellationToken),
+                Items = request.Items
+            };
         }
     }
 }

State Management/daprstate/src/ShoppingCart/Activities/Cart/Post/Post.cs

@@ -19,22 +19,28 @@ public Post(IMediator mediator)
         {
             _mediator = mediator;
         }
-        
+
         [HttpPost]
         [SwaggerOperation(
             Summary = "Create a shopping cart for a user",
             Description = "Create a shopping cart for a user",
             OperationId = "4D730510-3399-4324-BB2D-0A6C7270F783",
-            Tags = new[] {Routes.Cart})
+            Tags = new[] { Routes.Cart })
         ]
         [ProducesResponseType(StatusCodes.Status201Created)]
-       public async override Task<ActionResult> HandleAsync([FromRoute] Command request, CancellationToken cancellationToken = new CancellationToken())
+        [ProducesErrorResponseType(typeof(ConflictResult))]
+        public override async Task<ActionResult> HandleAsync([FromRoute] Command request,
+            CancellationToken cancellationToken = new CancellationToken())
         {
-           var response=  await _mediator.Send(request, cancellationToken);
-             return new CreatedResult(
-                 new Uri($"/{Routes.Cart}/{request.Session}", UriKind.Relative), response);
+            var response = await _mediator.Send(request, cancellationToken);
+
+            return response.Exists
+                ? new ConflictResult()
+                : new CreatedResult(
+                    new Uri($"/{Routes.Cart}/{request.Session}", UriKind.Relative), response.Items);
         }
     }
 }
 
+
 //dapr run --app-id "article-service" --app-port "5001" --dapr-grpc-port "50010" --dapr-http-port "5010" --components-path "./components" -- dotnet run --project ./ShoppingCart.csproj --urls="http://+:5001"

State Management/daprstate/src/ShoppingCart/Activities/Cart/Post/Response.cs

@@ -6,5 +6,6 @@ namespace ShoppingCart.Content.Activities.Cart.Post
     public class Response
     {
         public List<Item> Items { get; set; }
+        public bool Exists { get; set; }
     }
 }

State Management/daprstate/src/ShoppingCart/Exceptions/DaprStateException.cs

@@ -1,10 +1,12 @@
 using System;
+using System.Collections.Generic;
 
 namespace ShoppingCart.Content.Exceptions
 {
     public class DaprStateException : Exception
     {
-        public DaprStateException(string title, string message) : base(message) => Title = title;
+        public DaprStateException(string title, string message, IReadOnlyDictionary<string, string[]> errors) : base(message) => Title = title;
         public string Title { get; set; }
+        public IReadOnlyDictionary<string, string[]> Errors { get; }
     }
 }

State Management/daprstate/src/ShoppingCart/Exceptions/NotFoundException.cs

@@ -1,12 +1,13 @@
 using System;
+using System.Collections.Generic;
 using ShoppingCart.Resources;
 
 namespace ShoppingCart.Content.Exceptions
 {
     [Serializable]
     public class NotFoundException : DaprStateException
     {
-        public NotFoundException(string title, string message) : base(ExceptionTitle.NotFound, message)
+        public NotFoundException( string message, IReadOnlyDictionary<string, string[]> errors) : base(ExceptionTitle.NotFound, message, errors)
         {
         }
     }

State Management/daprstate/src/ShoppingCart/Exceptions/ValidationException.cs

@@ -5,9 +5,9 @@ namespace ShoppingCart.Content.Exceptions
 {
     public class ValidationException : DaprStateException
     {
-        public ValidationException( string message, IReadOnlyDictionary<string, string[]> errors) : base(ExceptionTitle.Validation , message) =>
-            Errors = errors;
-
-        public IReadOnlyDictionary<string, string[]> Errors { get; }
+        public ValidationException(string message, IReadOnlyDictionary<string, string[]> errors) : base(
+            ExceptionTitle.Validation, message, errors)
+        {
+        }
     }
 }

State Management/daprstate/src/ShoppingCart/Middleware/ExceptionHandlingMiddleware.cs

@@ -62,11 +62,12 @@ private static IReadOnlyDictionary<string, string[]> GetErrors(Exception excepti
         {
             IReadOnlyDictionary<string, string[]> errors = null;
 
-            if (exception is ValidationException validationException)
+            if (exception is DaprStateException baseException)
             {
-                errors = validationException.Errors;
+                return baseException.Errors;
             }
-
+
+
             return errors;
         }
     }

State Management/daprstate/src/ShoppingCart/Services/CartStateService.cs

@@ -1,37 +1,46 @@
 using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
 using System.Threading.Tasks;
 using Dapr.Client;
 using Microsoft.AspNetCore.JsonPatch;
 using ShoppingCart.Content.Activities.Cart.Post.Models;
+using ShoppingCart.Content.Exceptions;
 
 namespace ShoppingCart.Content.Activities.Cart.Post
 {
     public class CartStateService : IService<Item>
     {
-        private const string DAPR_STORE_NAME = "cart";
+        private const string DAPR_STORE_NAME = "cart-service";
         private readonly DaprClient _client;
 
         public CartStateService(DaprClient client)
         {
             _client = client;
         }
 
-        public async Task<List<Item>> Update(string session, JsonPatchDocument<List<Item>> items)
+        public async Task<List<Item>> Update(string session, JsonPatchDocument<List<Item>> items,  CancellationToken cancellationToken)
         {
-            var currentItems = await Get(session);
+            var (currentItems, etag) = await _client.GetStateAndETagAsync<List<Item>>(DAPR_STORE_NAME, session, cancellationToken: cancellationToken);
             items.ApplyTo(currentItems);
-            await Save(session, currentItems);
+            await _client.TrySaveStateAsync(DAPR_STORE_NAME, session, currentItems, etag, cancellationToken: cancellationToken);
             return currentItems;
         }
-
-        public async Task Save(string session, List<Item> entity)
+        public async Task<bool> Save(string session, List<Item> entity,  CancellationToken cancellationToken)
        {
-           await  _client.SaveStateAsync(DAPR_STORE_NAME, session , entity);
+           var stateEntry = await _client.GetStateEntryAsync<List<Item>>(DAPR_STORE_NAME, session, default, cancellationToken: cancellationToken);
+           if (stateEntry.Value is not null) return true;
+           await _client.SaveStateAsync(DAPR_STORE_NAME, session, entity, cancellationToken: cancellationToken);
+           return false;
+
        }
 
-       public async Task<List<Item>>Get(string session)
+       public async Task<List<Item>>Get(string session,  CancellationToken cancellationToken)
        {
-           return  await _client.GetStateAsync<List<Item>>(DAPR_STORE_NAME, session, ConsistencyMode.Strong);
+          return await _client.GetStateAsync<List<Item>>(DAPR_STORE_NAME, session, ConsistencyMode.Strong, cancellationToken: cancellationToken);
+
        }
+
+
     }
 }

State Management/daprstate/src/ShoppingCart/Services/IService.cs

@@ -1,13 +1,14 @@
 using System.Collections.Generic;
+using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.JsonPatch;
 
 namespace ShoppingCart.Content.Activities.Cart.Post
 {
     public interface IService<T> where T : class
     {
-        Task<List<T>> Update(string session, JsonPatchDocument<List<T>> items);
-        Task Save(string session, List<T> entity);
-        Task<List<T>> Get(string session);
+        Task<List<T>> Update(string session, JsonPatchDocument<List<T>> items, CancellationToken cancellationToken);
+        Task<bool> Save(string session, List<T> entity,  CancellationToken cancellationToken);
+        Task<List<T>> Get(string session,  CancellationToken cancellationToken);
     }
 }

State Management/daprstate/src/ShoppingCart/components/mongo.yaml

@@ -1,22 +1,22 @@
 apiVersion: dapr.io/v1alpha1
 kind: Component
 metadata:
-  name: cart
+  name: cart-service
 spec:
   type: state.mongodb
   version: v1
   metadata:
     - name: keyPrefix
-      value: appid
+      value: name
     - name: host
       value: localhost:27017
     - name: username
       value: dapr
     - name: password
       value: daprPassword 
     - name: databaseName
-      value: admin 
+      value: admin
     - name: collectionName
       value: cart 
-scopes:
-  - cart-service
+  scopes:
+   - cart-service

State Management/daprstate/src/ShoppingCart/obj/Debug/net5.0/ShoppingCart.csproj.CoreCompileInputs.cache

@@ -1 +1 @@
-52bde6a5a5838dc6c49cc744b5a919bb856714d2
+d8886b9e2c6471a0dae77374cf1e75b015a8405d

State Management/daprstate/src/ShoppingCart/obj/rider.project.restore.info

@@ -1 +1 @@
-16360564658755498
+16365798909296117

State Management/daprstate/src/http-client.env.json

@@ -1,7 +1,6 @@
 {
   "dev": {
-    "host-url": "localhost:5001/",
-    "session-id": "9F520260-2CB4-462A-BA04-C2F7CFAB1EFE",
-    "create-session-id": "93416A7B-A2B6-4CC8-AE94-9CD6BE89AE32"
+    "host-url": "localhost:5001",
+    "session-id": "D80D2408-4946-4A66-879C-CED411CBD0CB"
   }
 }