Use HTTP Status Codes

Author: rasor

Contracts/interfaces/IBookService.yaml

@@ -43,6 +43,10 @@ paths:
       responses:
         200:
           description: OK
+        201:
+          description: "Book created"
+        409:
+          description: "Book exist"
         default:
           description: failed
           schema:
@@ -64,6 +68,10 @@ paths:
       responses:
         200:
           description: OK
+        404:
+          description: "Book not found"
+        405:
+          description: "Validation exception"
         default:
           description: failed
           schema:
@@ -83,6 +91,8 @@ paths:
       tags:
         - IBookService
       responses:
+        404:
+          description: "Book not found"
         200:
           description: OK
           schema:

README.md

@@ -118,10 +118,62 @@ In most cases the best thing is to create yet a WCF service using the same contr
 - GET <http://localhost:15563/RestService1.svc/Book/1> in Postman
 - => Response: `{"Id": 1, "Name": "The incredible stamp"}`
 
+## Use HTTP Status Codes 
+
+18. Add HTTP Status Codes to your service
+- In your service `RestService1.svc.cs` - method `AddBook()` add content
+```CSharp
+            WebOperationContext.Current.OutgoingResponse.StatusCode = System.Net.HttpStatusCode.Created; // 201
+            if (book.Name == "The incredible stamp") {   // Book exist
+                WebOperationContext.Current.OutgoingResponse.StatusCode = System.Net.HttpStatusCode.Conflict; // 409
+            }
+```
+  - In method `UpdateBook()` add content
+```CSharp
+            if (book.Id == 2) { // Book does not exist - 404
+                WebOperationContext.Current.OutgoingResponse.SetStatusAsNotFound("Resource not found");
+            } else if (book.Name == "") { // Invalid request
+                WebOperationContext.Current.OutgoingResponse.StatusCode = System.Net.HttpStatusCode.MethodNotAllowed; // 405
+            }
+```
+  - In method `GetBookById()` add content
+```CSharp
+            if (id == "2") { // Book does not exist - 404
+                WebOperationContext.Current.OutgoingResponse.SetStatusAsNotFound("Resource not found");
+                return null;
+            } else {
+                return new Book() { Id = 1, Name = "The incredible stamp" };
+            }
+```
+- Follow the guidance for HTTP Status Codes in <https://developers.redhat.com/blog/2017/01/19/applying-api-best-practices-in-fuse/>
+- => Test the change using Postman
+19. Update your yaml with the Status Codes
+- In `IBookService.yaml`
+```yaml
+    put:
+      responses:
+        201:
+          description: "Book created"
+        409:
+          description: "Book exist"
+    post:
+      responses:
+        404:
+          description: "Book not found"
+        405:
+          description: "Validation exception"
+    get:
+      responses:
+        404:
+          description: "Book not found"
+```
+
 ## Refs 
 - Postman: <https://www.getpostman.com/> or <https://chrome.google.com/webstore/detail/postman/fhbjgbiflinjbdggehcddcbncdddomop?hl=en>
 - Swagger4WCF: <https://www.codeproject.com/Tips/1190441/How-to-generate-basic-swagger-yaml-description-for>
 - NuGet Swagger4WCF: <https://www.nuget.org/packages/Swagger4WCF>
 - Unity.WCF: <https://www.devtrends.co.uk/blog/introducing-unity.wcf-providing-easy-ioc-integration-for-your-wcf-services>
+- Set StatusCode: <https://codeblitz.wordpress.com/2009/04/27/how-to-host-and-consume-wcf-restful-services/>
+- API Best Practices: <https://developers.redhat.com/blog/2017/01/19/applying-api-best-practices-in-fuse/#>
 
 The End

WebApplicationWcfRest1/README.txt

@@ -98,9 +98,55 @@
 - GET http://localhost:15563/RestService1.svc/Book/1 in Postman
 => Response: {"Id": 1, "Name": "The incredible stamp"}
 
+-------- TFS Changeset 8 - Use HTTP Status Codes ---------------------
+18. Add HTTP Status Codes to your service
+- In your service RestService1.svc.cs
+-- In method AddBook() add content
+            WebOperationContext.Current.OutgoingResponse.StatusCode = System.Net.HttpStatusCode.Created; // 201
+            if (book.Name == "The incredible stamp") {   // Book exist
+                WebOperationContext.Current.OutgoingResponse.StatusCode = System.Net.HttpStatusCode.Conflict; // 409
+            }
+-- In method UpdateBook() add content
+            if (book.Id == 2) { // Book does not exist - 404
+                WebOperationContext.Current.OutgoingResponse.SetStatusAsNotFound("Resource not found");
+            } else if (book.Name == "") { // Invalid request
+                WebOperationContext.Current.OutgoingResponse.StatusCode = System.Net.HttpStatusCode.MethodNotAllowed; // 405
+            }
+-- In method GetBookById() add content
+            if (id == "2") { // Book does not exist - 404
+                WebOperationContext.Current.OutgoingResponse.SetStatusAsNotFound("Resource not found");
+                return null;
+            } else {
+                return new Book() { Id = 1, Name = "The incredible stamp" };
+            }
+- Follow the guidance for HTTP Status Codes in https://developers.redhat.com/blog/2017/01/19/applying-api-best-practices-in-fuse/
+=> Test the change using Postman
+19. Update your yaml with the Status Codes
+- In IBookService.yaml
+-- 
+    put:
+      responses:
+        201:
+          description: "Book created"
+        409:
+          description: "Book exist"
+    post:
+      responses:
+        404:
+          description: "Book not found"
+        405:
+          description: "Validation exception"
+    get:
+      responses:
+        404:
+          description: "Book not found"
+
 Ref: 
+- Postman: https://www.getpostman.com/ or https://chrome.google.com/webstore/detail/postman/fhbjgbiflinjbdggehcddcbncdddomop?hl=en
 - Swagger4WCF: https://www.codeproject.com/Tips/1190441/How-to-generate-basic-swagger-yaml-description-for
 - NuGet Swagger4WCF: https://www.nuget.org/packages/Swagger4WCF
 - Unity.WCF: https://www.devtrends.co.uk/blog/introducing-unity.wcf-providing-easy-ioc-integration-for-your-wcf-services
+- Set StatusCode: https://codeblitz.wordpress.com/2009/04/27/how-to-host-and-consume-wcf-restful-services/
+- API Best Practices: https://developers.redhat.com/blog/2017/01/19/applying-api-best-practices-in-fuse/#
 
 The End

WebApplicationWcfRest1/RestService1.svc.cs

@@ -1,5 +1,6 @@
 using System.Diagnostics;
 using System.ServiceModel.Activation;
+using System.ServiceModel.Web;
 using WebApplicationWcfRest1.interfaces;
 using WebApplicationWcfRest1.models;
 
@@ -12,6 +13,10 @@ public class RestService1 : IBookService
         public void AddBook(Book book)
         {
             Debug.WriteLine(book.Name);
+            WebOperationContext.Current.OutgoingResponse.StatusCode = System.Net.HttpStatusCode.Created; // 201
+            if (book.Name == "The incredible stamp") { // Book exist
+                WebOperationContext.Current.OutgoingResponse.StatusCode = System.Net.HttpStatusCode.Conflict; // 409
+            }
         }
 
         public void DeleteBook(string id)
@@ -21,7 +26,12 @@ public void DeleteBook(string id)
 
         public Book GetBookById(string id)
         {
-            return new Book() {Id = 1, Name= "The incredible stamp" };
+            if (id == "2") { // Book does not exist - 404
+                WebOperationContext.Current.OutgoingResponse.SetStatusAsNotFound("Resource not found");
+                return null;
+            } else {
+                return new Book() { Id = 1, Name = "The incredible stamp" };
+            }
         }
 
         public Book[] GetBooksList()
@@ -32,6 +42,11 @@ public Book[] GetBooksList()
         public void UpdateBook(Book book)
         {
             Debug.WriteLine(book.Name);
+            if (book.Id == 2) { // Book does not exist - 404
+                WebOperationContext.Current.OutgoingResponse.SetStatusAsNotFound("Resource not found");
+            } else if (book.Name == "") { // Invalid request
+                WebOperationContext.Current.OutgoingResponse.StatusCode = System.Net.HttpStatusCode.MethodNotAllowed; // 405
+            }
         }
     }
 }