I have ASP.NETCORE 3.1 WEBAPI , Azure SQL server as the database for an application.
In order to avoid repetitive code, I thought of implementing a filter which will decide the HTTP Status code based on the result return from the API endpoint. The idea here is remove the duplicate code related to setting up the result returned along with HTTP Status code always.
I wanted to know is it good practice to move away from the traditional approach of sending the response back to client with result and appropriate HTTP Status code from the action method itself or delegate it to an action filter post execution of the action method.
Code (Without Filter):
[HttpGet("{param1:long}", Name = "GetData")]
[ResponseCache(CacheProfileName = "Never")]
[ProducesResponseType(200)]
[ProducesResponseType(400)]
[ProducesResponseType(500)]
public async Task<ActionResult<TestModel>> GetData(long param1)
{
var result = await _testService.GetData(param1);
return result is null ? NotFound() : (ActionResult<TestModel>)Ok(result);
}
Code (With Filter)
[HttpGet("{param1:long}", Name = "GetData")]
[ResponseCache(CacheProfileName = "Never")]
[ProducesResponseType(200)]
[ProducesResponseType(400)]
[ProducesResponseType(500)]
[ServiceFilter(typeof(StatusFilter))]
public async Task<ActionResult<TestModel>> GetData(long param1)=>
await _testService.GetData(param1);
// Filter to handle the HTTP Status code
public class StatusFilter : ActionFilterAttribute
{
public override void OnActionExecuting(ActionExecutingContext context)
{
}
public override void OnActionExecuted(ActionExecutedContext context)
{
var value = ((Microsoft.AspNetCore.Mvc.ObjectResult)context.Result).Value;
if (value is null)
{
context.Result = new NotFoundResult(value);
}
else
{
context.Result = new OkObjectResult(value);
}
}
}
Is there any better approach in order to implement it.
Can anyone help me here by providing their guidance?
I've 7 actions in my controllers. I've refactored them an was able to isolate the common portion.
public IActionResult Get()
{
var response = CommonCode();
}
public IActionResult Get(guid id)
{
var response = CommonCode();
}
public IActionResult Post(ViewModel vm)
{
var response = CommonCode();
}
This is where I refactored the common code.
provate IActionResult CommonCode()
{
if(userHasNoPermission())
return Forbid();
if(IdProvidedDoesntExist())
return BadRequest();
//...
}
When I look inside the response, I see only one method: ExecuteResultAsync().
Is there a way to retrieve the HTTP code that I sent inside the helper method?
I'd like for instance to stop the processing if it's 500, retrieve the message to add to the ModelState* if it's 400, but proceed if it's OK.
There are a few "filthy" ways you can do it without a case statement. The status code is actually in the result but IActionResult and ActionResult hate being cast to a common type.
This example takes a IActionResult from any common result and rips the status code out using reflection. If you don't mind doing it that way it saves requiring the case statement to pattern match. The same can be done for the content.
public static HttpStatusCode GetHttpStatusCode(IActionResult functionResult)
{
try
{
return (HttpStatusCode)functionResult
.GetType()
.GetProperty("StatusCode")
.GetValue(functionResult, null);
}
catch
{
return HttpStatusCode.InternalServerError;
}
}
The return of CommonCode is simply some type of IActionResult. The "result" is not actually a "response". That comes later when the action is fully returned back into the request pipeline (which has not occurred yet when you're calling the method directly in code). As result, concepts like HTTP status code aren't even relevant yet. If you return something like StatusCodeResult, that's technically only a suggested status code. If there's an exception later in the request pipeline or some piece of middleware explicitly changes the status code for some reason, it will be different.
Long and short, you're trying to conflate two unrelated things together. I think you simply want to know what happened in CommonCode, and think the HTTP status is the best way to determine that. In actuality, you'd be better served by returning a tuple or doing something like pattern matching:
With a tuple, you can essentially return more than one thing from your CommonCode method. For example, you could do something like:
private (int, IActionResult) CommonCode()
{
if(userHasNoPermission())
return (403, Forbid());
if(IdProvidedDoesntExist())
return (400, BadRequest());
//...
}
Then:
public IActionResult Get()
{
(var status, var response) = CommonCode();
// branch on `status`
}
Or, with pattern matching:
public IActionResult Get()
{
var response = CommonCode();
switch (response)
{
case ForbidResult forbid:
// do something for forbidden
break;
case BadRequestResult badRequest:
// do something for bad request
break;
}
}
I had a similar problem returning Ok() and NotFound(). I
was able to get the status code using the IStatusCodeActionResult interface.
((IStatusCodeActionResult)response).StatusCode;
You could return the statuscode itself from the private method. for example
private IActionResult CommonCode() {
if(userHasNoPermission())
return StatusCode(401);
if(IdProvidedDoesntExist())
return StatusCode(400);
//... }
then in your method just check for the status code
public IActionResult Post(ViewModel vm)
{
var response = CommonCode();
if (this.HttpContext.Response.StatusCode == 418)
Console.WriteLine("I'm a teapot")
else {
return response;
}
}
Environment:
I am working in WebAPI. I implemented all CRUD methods.
Scenario:
In PUT method, i am excluding some properties like 'CreatedDate' to be updated. My Code like below;
[Route("")]
public async Task<IHttpActionResult> Put(MyModel myModel)
{
//Parsing to Business Entity
var item = TheFactory.Parse(myModel);
bool result = await _myBL.UpdateLab(item);
if (!result)
{
return BadRequest("Error in Save");
}
//Converting to view model and return
return Ok(TheFactory.Create(item));
}
Problem:
Here i am not getting CreatedDate from user. So it always min date.In DAL i specified this field as not modified so it always have the created data value. In return i am converting to viewmodel from the model user given. So CreatedDate is min date not original.
MySolution:
So to avoid that get the updated object from the Database again and return to the user. I already have get method to return the object by passing id. So i just changed my PUT method like below;
[Route("")]
public async Task<IHttpActionResult> Put(MyModel myModel)
{
//Parsing to Business Entity
var item = TheFactory.Parse(myModel);
bool result = await _myBL.UpdateLab(item);
if (!result)
{
return BadRequest("Error in Save");
}
//Redirect to getbyid method
return RedirectToRoute("GetById", new { id = item.Id });
}
Issue:
Here i thought i can reuse the method get method so it also returns ok(object). But after changed to this I got the following exception;
The requested resource does not support http method 'PUT'.
The response status is 405. Please help me to find the routecause
You need to just call GetById(item.id)
[Route("")]
public async Task<IHttpActionResult> Put(MyModel myModel)
{
//Parsing to Business Entity
var item = TheFactory.Parse(myModel);
bool result = await _myBL.UpdateLab(item);
if (!result)
{
return BadRequest("Error in Save");
}
return GetById(item.Id);
}
I'm looking for the correct way to return JSON with a HTTP status code in my .NET Core Web API controller. I use to use it like this:
public IHttpActionResult GetResourceData()
{
return this.Content(HttpStatusCode.OK, new { response = "Hello"});
}
This was in a 4.6 MVC application but now with .NET Core I don't seem to have this IHttpActionResult I have ActionResult and using like this:
public ActionResult IsAuthenticated()
{
return Ok(Json("123"));
}
But the response from the server is weird, as in the image below:
I just want the Web API controller to return JSON with a HTTP status code like I did in Web API 2.
The most basic version responding with a JsonResult is:
// GET: api/authors
[HttpGet]
public JsonResult Get()
{
return Json(_authorRepository.List());
}
However, this isn't going to help with your issue because you can't explicitly deal with your own response code.
The way to get control over the status results, is you need to return a ActionResult which is where you can then take advantage of the StatusCodeResult type.
for example:
// GET: api/authors/search?namelike=foo
[HttpGet("Search")]
public IActionResult Search(string namelike)
{
var result = _authorRepository.GetByNameSubstring(namelike);
if (!result.Any())
{
return NotFound(namelike);
}
return Ok(result);
}
Note both of these above examples came from a great guide available from Microsoft Documentation: Formatting Response Data
Extra Stuff
The issue I come across quite often is that I wanted more granular control over my WebAPI rather than just go with the defaults configuration from the "New Project" template in VS.
Let's make sure you have some of the basics down...
Step 1: Configure your Service
In order to get your ASP.NET Core WebAPI to respond with a JSON Serialized Object along full control of the status code, you should start off by making sure that you have included the AddMvc() service in your ConfigureServices method usually found in Startup.cs.
It's important to note thatAddMvc() will automatically include the Input/Output Formatter for JSON along with responding to other request types.
If your project requires full control and you want to strictly define your services, such as how your WebAPI will behave to various request types including application/json and not respond to other request types (such as a standard browser request), you can define it manually with the following code:
public void ConfigureServices(IServiceCollection services)
{
// Build a customized MVC implementation, without using the default AddMvc(), instead use AddMvcCore().
// https://github.com/aspnet/Mvc/blob/dev/src/Microsoft.AspNetCore.Mvc/MvcServiceCollectionExtensions.cs
services
.AddMvcCore(options =>
{
options.RequireHttpsPermanent = true; // does not affect api requests
options.RespectBrowserAcceptHeader = true; // false by default
//options.OutputFormatters.RemoveType<HttpNoContentOutputFormatter>();
//remove these two below, but added so you know where to place them...
options.OutputFormatters.Add(new YourCustomOutputFormatter());
options.InputFormatters.Add(new YourCustomInputFormatter());
})
//.AddApiExplorer()
//.AddAuthorization()
.AddFormatterMappings()
//.AddCacheTagHelper()
//.AddDataAnnotations()
//.AddCors()
.AddJsonFormatters(); // JSON, or you can build your own custom one (above)
}
You will notice that I have also included a way for you to add your own custom Input/Output formatters, in the event you may want to respond to another serialization format (protobuf, thrift, etc).
The chunk of code above is mostly a duplicate of the AddMvc() method. However, we are implementing each "default" service on our own by defining each and every service instead of going with the pre-shipped one with the template. I have added the repository link in the code block, or you can check out AddMvc() from the GitHub repository..
Note that there are some guides that will try to solve this by "undoing" the defaults, rather than just not implementing it in the first place... If you factor in that we're now working with Open Source, this is redundant work, bad code and frankly an old habit that will disappear soon.
Step 2: Create a Controller
I'm going to show you a really straight-forward one just to get your question sorted.
public class FooController
{
[HttpPost]
public async Task<IActionResult> Create([FromBody] Object item)
{
if (item == null) return BadRequest();
var newItem = new Object(); // create the object to return
if (newItem != null) return Ok(newItem);
else return NotFound();
}
}
Step 3: Check your Content-Type and Accept
You need to make sure that your Content-Type and Accept headers in your request are set properly. In your case (JSON), you will want to set it up to be application/json.
If you want your WebAPI to respond as JSON as default, regardless of what the request header is specifying you can do that in a couple ways.
Way 1
As shown in the article I recommended earlier (Formatting Response Data) you could force a particular format at the Controller/Action level. I personally don't like this approach... but here it is for completeness:
Forcing a Particular Format If you would like to restrict the response formats for a specific action you can, you can apply the
[Produces] filter. The [Produces] filter specifies the response
formats for a specific action (or controller). Like most Filters, this
can be applied at the action, controller, or global scope.
[Produces("application/json")]
public class AuthorsController
The [Produces] filter will force all actions within the
AuthorsController to return JSON-formatted responses, even if other
formatters were configured for the application and the client provided
an Accept header requesting a different, available format.
Way 2
My preferred method is for the WebAPI to respond to all requests with the format requested. However, in the event that it doesn't accept the requested format, then fall-back to a default (ie. JSON)
First, you'll need to register that in your options (we need to rework the default behavior, as noted earlier)
options.RespectBrowserAcceptHeader = true; // false by default
Finally, by simply re-ordering the list of the formatters that were defined in the services builder, the web host will default to the formatter you position at the top of the list (ie position 0).
More information can be found in this .NET Web Development and Tools Blog entry
You have predefined methods for most common status codes.
Ok(result) returns 200 with response
CreatedAtRoute returns 201 + new resource URL
NotFound returns 404
BadRequest returns 400 etc.
See BaseController.cs and Controller.cs for a list of all methods.
But if you really insist you can use StatusCode to set a custom code, but you really shouldn't as it makes code less readable and you'll have to repeat code to set headers (like for CreatedAtRoute).
public ActionResult IsAuthenticated()
{
return StatusCode(200, "123");
}
With ASP.NET Core 2.0, the ideal way to return object from Web API (which is unified with MVC and uses same base class Controller) is
public IActionResult Get()
{
return new OkObjectResult(new Item { Id = 123, Name = "Hero" });
}
Notice that
It returns with 200 OK status code (it's an Ok type of ObjectResult)
It does content negotiation, i.e. it'll return based on Accept header in request. If Accept: application/xml is sent in request, it'll return as XML. If nothing is sent, JSON is default.
If it needs to send with specific status code, use ObjectResult or StatusCode instead. Both does the same thing, and supports content negotiation.
return new ObjectResult(new Item { Id = 123, Name = "Hero" }) { StatusCode = 200 };
return StatusCode( 200, new Item { Id = 123, Name = "Hero" });
or even more fine grained with ObjectResult:
Microsoft.AspNetCore.Mvc.Formatters.MediaTypeCollection myContentTypes = new Microsoft.AspNetCore.Mvc.Formatters.MediaTypeCollection { System.Net.Mime.MediaTypeNames.Application.Json };
String hardCodedJson = "{\"Id\":\"123\",\"DateOfRegistration\":\"2012-10-21T00:00:00+05:30\",\"Status\":0}";
return new ObjectResult(hardCodedJson) { StatusCode = 200, ContentTypes = myContentTypes };
If you specifically want to return as JSON, there are couple of ways
//GET http://example.com/api/test/asjson
[HttpGet("AsJson")]
public JsonResult GetAsJson()
{
return Json(new Item { Id = 123, Name = "Hero" });
}
//GET http://example.com/api/test/withproduces
[HttpGet("WithProduces")]
[Produces("application/json")]
public Item GetWithProduces()
{
return new Item { Id = 123, Name = "Hero" };
}
Notice that
Both enforces JSON in two different ways.
Both ignores content negotiation.
First method enforces JSON with specific serializer Json(object).
Second method does the same by using Produces() attribute (which is a ResultFilter) with contentType = application/json
Read more about them in the official docs. Learn about filters here.
The simple model class that is used in the samples
public class Item
{
public int Id { get; set; }
public string Name { get; set; }
}
The easiest way I came up with is :
var result = new Item { Id = 123, Name = "Hero" };
return new JsonResult(result)
{
StatusCode = StatusCodes.Status201Created // Status code here
};
This is my easiest solution:
public IActionResult InfoTag()
{
return Ok(new {name = "Fabio", age = 42, gender = "M"});
}
or
public IActionResult InfoTag()
{
return Json(new {name = "Fabio", age = 42, gender = "M"});
}
Awesome answers I found here and I also tried this return statement see StatusCode(whatever code you wish) and it worked!!!
return Ok(new {
Token = new JwtSecurityTokenHandler().WriteToken(token),
Expiration = token.ValidTo,
username = user.FullName,
StatusCode = StatusCode(200)
});
Instead of using 404/201 status codes using enum
public async Task<IActionResult> Login(string email, string password)
{
if (string.IsNullOrWhiteSpace(email) || string.IsNullOrWhiteSpace(password))
{
return StatusCode((int)HttpStatusCode.BadRequest, Json("email or password is null"));
}
var user = await _userManager.FindByEmailAsync(email);
if (user == null)
{
return StatusCode((int)HttpStatusCode.BadRequest, Json("Invalid Login and/or password"));
}
var passwordSignInResult = await _signInManager.PasswordSignInAsync(user, password, isPersistent: true, lockoutOnFailure: false);
if (!passwordSignInResult.Succeeded)
{
return StatusCode((int)HttpStatusCode.BadRequest, Json("Invalid Login and/or password"));
}
return StatusCode((int)HttpStatusCode.OK, Json("Sucess !!!"));
}
Controller action return types in ASP.NET Core web API
02/03/2020
6 minutes to read
+2
By Scott Addie Link
Synchronous action
[HttpGet("{id}")]
[ProducesResponseType(StatusCodes.Status200OK)]
[ProducesResponseType(StatusCodes.Status404NotFound)]
public ActionResult<Product> GetById(int id)
{
if (!_repository.TryGetProduct(id, out var product))
{
return NotFound();
}
return product;
}
Asynchronous action
[HttpPost]
[Consumes(MediaTypeNames.Application.Json)]
[ProducesResponseType(StatusCodes.Status201Created)]
[ProducesResponseType(StatusCodes.Status400BadRequest)]
public async Task<ActionResult<Product>> CreateAsync(Product product)
{
if (product.Description.Contains("XYZ Widget"))
{
return BadRequest();
}
await _repository.AddProductAsync(product);
return CreatedAtAction(nameof(GetById), new { id = product.Id }, product);
}
Please refer below code, You can manage multiple status code with different type JSON
public async Task<HttpResponseMessage> GetAsync()
{
try
{
using (var entities = new DbEntities())
{
var resourceModelList = entities.Resources.Select(r=> new ResourceModel{Build Your Resource Model}).ToList();
if (resourceModelList.Count == 0)
{
return this.Request.CreateResponse<string>(HttpStatusCode.NotFound, "No resources found.");
}
return this.Request.CreateResponse<List<ResourceModel>>(HttpStatusCode.OK, resourceModelList, "application/json");
}
}
catch (Exception ex)
{
return this.Request.CreateResponse<string>(HttpStatusCode.InternalServerError, "Something went wrong.");
}
}
What I do in my Asp Net Core Api applications it is to create a class that extends from ObjectResult and provide many constructors to customize the content and the status code.
Then all my Controller actions use one of the costructors as appropiate.
You can take a look at my implementation at:
https://github.com/melardev/AspNetCoreApiPaginatedCrud
and
https://github.com/melardev/ApiAspCoreEcommerce
here is how the class looks like(go to my repo for full code):
public class StatusCodeAndDtoWrapper : ObjectResult
{
public StatusCodeAndDtoWrapper(AppResponse dto, int statusCode = 200) : base(dto)
{
StatusCode = statusCode;
}
private StatusCodeAndDtoWrapper(AppResponse dto, int statusCode, string message) : base(dto)
{
StatusCode = statusCode;
if (dto.FullMessages == null)
dto.FullMessages = new List<string>(1);
dto.FullMessages.Add(message);
}
private StatusCodeAndDtoWrapper(AppResponse dto, int statusCode, ICollection<string> messages) : base(dto)
{
StatusCode = statusCode;
dto.FullMessages = messages;
}
}
Notice the base(dto) you replace dto by your object and you should be good to go.
I got this to work. My big issue was my json was a string (in my database...and not a specific/known Type).
Ok, I finally got this to work.
////[Route("api/[controller]")]
////[ApiController]
////public class MyController: Microsoft.AspNetCore.Mvc.ControllerBase
////{
//// public IActionResult MyMethod(string myParam) {
string hardCodedJson = "{}";
int hardCodedStatusCode = 200;
Newtonsoft.Json.Linq.JObject job = Newtonsoft.Json.Linq.JObject.Parse(hardCodedJson);
/* "this" comes from your class being a subclass of Microsoft.AspNetCore.Mvc.ControllerBase */
Microsoft.AspNetCore.Mvc.ContentResult contRes = this.Content(job.ToString());
contRes.StatusCode = hardCodedStatusCode;
return contRes;
//// } ////end MyMethod
//// } ////end class
I happen to be on asp.net core 3.1
#region Assembly Microsoft.AspNetCore.Mvc.Core, Version=3.1.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60
//C:\Program Files\dotnet\packs\Microsoft.AspNetCore.App.Ref\3.1.0\ref\netcoreapp3.1\Microsoft.AspNetCore.Mvc.Core.dll
I got the hint from here :: https://www.jianshu.com/p/7b3e92c42b61
The cleanest solution I have found is to set the following in my ConfigureServices method in Startup.cs (In my case I want the TZ info stripped. I always want to see the date time as the user saw it).
services.AddControllers()
.AddNewtonsoftJson(o =>
{
o.SerializerSettings.DateTimeZoneHandling = DateTimeZoneHandling.Unspecified;
});
The DateTimeZoneHandling options are Utc, Unspecified, Local or RoundtripKind
I would still like to find a way to be able to request this on a per-call bases.
something like
static readonly JsonMediaTypeFormatter _jsonFormatter = new JsonMediaTypeFormatter();
_jsonFormatter.SerializerSettings = new JsonSerializerSettings()
{DateTimeZoneHandling = DateTimeZoneHandling.Unspecified};
return Ok("Hello World", _jsonFormatter );
I am converting from ASP.NET and there I used the following helper method
public static ActionResult<T> Ok<T>(T result, HttpContext context)
{
var responseMessage = context.GetHttpRequestMessage().CreateResponse(HttpStatusCode.OK, result, _jsonFormatter);
return new ResponseMessageResult(responseMessage);
}
I have an issues which has just arisen.
I have a Web API that has this method:
[HttpGet]
[Route("")]
public IHttpActionResult Get(OrderRequestViewModel model)
{
var order = new orderHeader()
{
sordNo = model.OrderNumber,
process = orderHeader.orderProcesses.Read
};
order.processInfos.read_CoreHistory = model.ReadCoreHistory;
var response = this.Connection.webServicesAdvanced.ordersHubAction_S(this.SecurityToken, order);
switch (response.state)
{
case processorResult.resultEnum.failed:
case processorResult.resultEnum.validationfailed:
throw new HttpException(500, response.info);
default:
return Ok(new OrderResponseViewModel(response.obj));
}
}
The OrderRequestViewModel only has 2 properties: OrderNumber (string) and ReadCoreHistory (boolean).
In my Angular JS application I have a service which looks like this:
.factory('OrderService', ['$http', '$filter', 'apiUrl', function ($http, $filter, api) {
var _get = function (orderNumber, readCoreHistory) {
return $http.get(api + 'orders?orderNumber=' + orderNumber + '&readCoreHistory=' + readCoreHistory);
}
//-- removed for brevity --//
var service = {};
service.get = _get;
//-- removed for brevity --//
return service;
}])
When I call the get() method from my controller, if I have fiddler open it states:
No MediaTypeFormatter is available to read an object of type 'OrderRequestViewModel' from content with media type 'application/octet-stream'.
Apparently this is a content type header issue, but I have no access to the ajax call options that I can see. Does anyone know how I can solve this?
GET method does not have a body, complex types are filled by data from request body in ASP.NET WebAPI, you should add [FromUri] attribute before your complex type in method signature.
public IHttpActionResult Get([FromUri] OrderRequestViewModel model)
{ ...