I'm developing an Asp.Net Core API.
My controller declaration
[ApiController]
public class BarController : Controller
{
...
}
My endpoint looks like this
[HttpPost, Route("bars")]
public async Task<ActionResult> DoAsync(
[FromBody] UpdateBars command)
{
// Do something with the command
return Ok(result);
}
The command looks like this
public class UpdateBars
{
[Required]
public IEnumerable<string> Ids { get; set; }
// ... more properties
}
Compatibility level is set to 2.1
public IServiceProvider ConfigureSharedServices(IServiceCollection services)
{
// ...
services.AddMvc()
.AddControllersAsServices()
.SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
// ...
}
Old question: I'd expect this to return a 400 bad request with a missing Ids parameter, but it fails to return the binding error.
What am I doing wrong?
Updated question: I'd expect this to return a 400 bad request with a missing or empty Ids parameter. The response is as expected if the parameter is missing (null), but returns 200 ok if it is an empty collection.
Is it possible to change something so that I get a bad request when the parameter is present but empty?
You probably didn't put a [ApiController] attribute on your controller.
By default the validation is not 'automatic'.
If you don't want to put that attribute on your controller, you will have to validate the model yourself, in following way:
[HttpPost, Route("bars")]
public async Task<ActionResult> DoAsync(
[FromBody] UpdateBars command)
{
if (!ModelState.IsValid)
{
return BadRequest(ModelState);
}
// Do something with the command
return Ok(result);
}
You have more controll in that way, but if you just need to return a BadRequest with the model state, it will happen automatically if you put the [ApiController] on the controller.
Also in that case it will mark all action parameters as [FromBody], so putting that attribute on params is not needed
You should add the [ApiController] attribute. In that case, an automatic HTTP 400 response containing error details is returned when model state is invalid. For more information, see Automatic HTTP 400 responses. Automatic HTTP 400 responses.
Related
So I added a controller to a blank asp.net CORE Api.
public class IsAliveController : ControllerBase
{
[HttpPost]
[HttpGet]
[Route("isalive")]
public object Get()
{
return "I'm alive";
}
}
Then I try to access it via https://localhost:44361/isalive
and I get no response. Do I need to make some modifications to my Startup.cs?
First why have you declared your method both as a get and a post request? you can remove the post attribute.
By default your routing must start with your controller name, add this:
[Route("[controller]")]
[ApiController]
public class IsAliveController : ControllerBase
{
[HttpGet]
public object Get()
{
return "I'm alive";
}
}
Now when you call https://localhost:44361/isalive you will receive the expected response.
There are two solutions to your problem:
#1 Your controller Name is IsAlive and you have added a route attribute on your action method as isAlive, so this would work only if you call using this Url
https://localhost:44361/isalive/isalive
#2 Remove the Route attribute from the action method
public class IsAliveController : ControllerBase
{
[HttpGet]
public object Get()
{
return "I'm alive";
}
}
and you will be able to access using Url
https://localhost:44361/isalive
Found the issue. The template I choose (using Visual studio 2019) was:
Asp.net core web app > Web Application
The startup file in this template is missing a line that I needed to add:
app.UseEndpoints(endpoints =>
{
//Add this line
endpoints.MapControllers();
});
After adding that line the endpoint works without any changes to the controller.
I'm struggling with something very basic. I'm trying to be get a response from my WebApi2 restful service, and I can't.
I have not edited the default WebApi (WebApiConfig.cs) route.
This is the controller
public class AboutController
{
[Route("api/about/{id:int}/{service1}/{service2}")]
public async Task<IHttpActionResult> Get(int accountId, string mainservice, string secondaryservice)
{
//logic
}
}
If I navigate (in a browser) to http://localhost:58090/api/about I get the error message The requested resource does not support http method 'GET'. I guess this makes sense, as it doesn't match the route (path).
If I update the path to something which matches the signature, such as http://localhost:58090/api/about/1/a/b I get the error message No action was found on the controller About' that matches the request.
Even if I add [HttpGet] to the controller, it makes no difference.
As a sanity test, I updated to
public class AboutController
{
public async Task<IHttpActionResult> Get()
{
//logic
}
}
and it does what is expected. I'm lost as to why adding the parameters has confused things so much.
I'm lost as to what I've done wrong
The route must match the parameters
[Route("api/about/{id:int}/{service1}/{service2}")]
public async Task<IHttpActionResult> Get(int id, string mainService, string secondaryService)
{
The above won't work, because it is expecting to see service1 and service2 based upon the route.
Update as per the example below
[Route("api/about/{id:int}/{service1}/{service2}")]
public async Task<IHttpActionResult> Get(int id, string service1, string service2)
{
I'm working with an ASP.NET Core RazorPage as an alternative to an MVC controller, and I want to be able to submit the client side form via XMLHttpRequest. I've already figured out the XSRF token bits so that passes the muster, but the RazorPages framework doesn't seem to process the inbound JSON payload and bind it to the property as expected.
Some code:
The page's model (.cshtml.cs):
public class IndexModel : PageModel
{
private Database database;
private ILogger logger;
[BindProperty]
public AddRequestModel MyRequest { get; set; }
public IndexModel(Database database, ILogger<IndexModel> logger)
{
this.database = database;
this.logger = logger;
}
public void OnGet() {}
public IActionResult OnPostValidate()
{
if (ModelState.IsValid)
{
// ...
}
return new BadRequestObjectResult(ModelState);
}
public async Task<IActionResult> OnPutConfirmAsync()
{
// ...
}
}
And the client side post:
const url = "?handler=validate";
const data = { MyRequest: this.fields };
await axios.post(url, data);
I have verified the data is being submitted correctly:
That X-XSRF-TOKEN header is being added by axios before the request is submitted. The fact that the server responds with a list of errors indicates that it's not the XSRF token causing the problem:
Note the MyRequest object does not contain the values from the request payload - it was not bound as expected (FirstName would not return a required error otherwise). How can I tell RazorPages to accept the JSON request and bind it to my property?
I was able to get the Binding works by adding FromBody similar to how it worked for ASP.NET Web API 2.
[BindProperty, FromBody]
public BroadcastMessageEditingViewModel BindingInfo { get; set; }
Use urlsearchparams with formdata.
In this post you can find more information How do I post form data with fetch api?
You would be better off posting your data to an API endpoint instead of a page controller. Create a class from ControllerBase and it will handle your JSON post correctly.
My route is correctly configured, and my methods have the decorated tag.
Method "GetMessage" work fine but "DeleteAllLoc" return "The requested resource does not support http method 'GET'.".
They are the same...What is problem?
[RoutePrefix("api/Loc")]
public class LocController : ApiController
{
[Route("DeleteAllLoc")]
public string DeleteAllLoc()
{
return "OK";
}
[Route("GetMessage")]
public string GetMessage()
{
return "Hello";
}
}
Decorate your DeleteAllLoc method with the [HttpGet] attribute to specify that it's a GET request - I think it's inferring it as a DELETE because of the method name.
I am curious why the ApiController handles default parameter values on actions differently than a 'regular' Controller.
This code works just fine, request to /Test means page gets value 1
public class TestController : Controller
{
public ActionResult Index(int page = 1)
{
return View(page);
}
}
This code doesn't work when a request is made to /api/Values. It fails with:
"The parameters dictionary contains a null entry for parameter 'page' of non-nullable type 'System.Int32' for method 'System.Collections.Generic.IEnumerable`1[System.String] Get(Int32)' in 'MvcApplication1.Controllers.Controllers.ValuesController'. An optional parameter must be a reference type, a nullable type, or be declared as an optional parameter."
public class ValuesController : ApiController
{
public IEnumerable<string> Get(int page = 1)
{
return new string[] { page.ToString() };
}
}
Any hints on why this is?
Try adding the [FromUri] or [FromForm] parameter attribute.
public class ValuesController : ApiController
{
public IEnumerable<string> Get([FromUri]int page = 1)
{
return new string[] { page.ToString() };
}
}
Mike Stall has two good posts about parameter binding in Webapi which does not work as it does in ASP MVC. The big problem to get used to is that you can only read the request body once in your pipeline. So if you need to read more than 1 complex object as a parameter, you probably need to resort to ModelBinding by parameter. I had a problem similar to yours when I was reading the content body earlier in the pipeline for logging purposes and did not realize about the read once restriction above and had to solve with my own custom model binder.
Explains model binding at http://blogs.msdn.com/b/jmstall/archive/2012/04/16/how-webapi-does-parameter-binding.aspx and then suggests a way to make WebAPI model binding more like ASP MVC http://blogs.msdn.com/b/jmstall/archive/2012/04/18/mvc-style-parameter-binding-for-webapi.aspx
Try defining as Nullable<T>:
public class ValuesController : ApiController
{
public IEnumerable<string> Get(int? page = 1)
{
return new string[] { page.ToString() };
}
}