We are integrating with mobile software company to do our application in a mobile device.
Our controller has ( simplification) methods like :
api/users/1
–GetUserById(...)
api/users/changePassword
–ChangePassword(Person p)
Ok.
The ChangePassword can return several applicative error codes ( password has already used , password too short , password bla bla...)
So if ,for example, password has already been used , then the HttpCode should be 200 returned with additional info
We agreed on this convention for every response :( additional to the response data)
{
"Success":0,
"ErrorCode": 6,
"ErrorMessage":"already used"
}
But this structure , as I said - should be in every response.
So till now - for example : api/users/1 returned :
{
"userId":1,
"name":"John"
}
But now - the response should be :
{
"data":
{
"userId":1,
"name":"John"
}
,
"result": //no errors
{
"Success":0,
"ErrorCode": 0,
"ErrorMessage":""
}
}
They always looking for the "result" object to see the applicative response.
Question
I assume that the place which I should do it is in message handler after base.SendAsync ( response part)
But how should I wrap the regular response which I send via Request.CreateResponseMessage with the format + values of :
NB , of course at the Request.CreateResponseMessage phase I already have result object with the appropriate result codes.
By the time message handlers run in Web API pipeline, the result your action method has produced would have been serialized. An action filter would be a better option, since you can deal with objects, and you can do something like this.
public class MyActionFilterAttribute : ActionFilterAttribute
{
public override void OnActionExecuted(HttpActionExecutedContext context)
{
var content = context.Response.Content as ObjectContent;
if (content != null)
{
content.Value =
new MyResponse()
{
Result = new Result() { Success = 0, ErrorCode = 6 },
Data = content.Value
};
}
}
}
public class Result
{
public int Success { get; set; }
public int ErrorCode { get; set; }
}
public class MyResponse
{
public Result Result { get; set; }
public object Data { get; set; }
}
Note: The above code will work only for JSON and not XML.
You can create an ActionFilterAttribute, and on the OnActionExecuted Method you will get HttpActionExecutedContext where you can check the response message.
you can decorate your controlleror action by this attribute and return and create you own ResponseMessage.
Hope that helps.
Related
I am learning Blazor, and I have a WebAssembly client application.
I created a WebAPI at the server which does some additional validation over and above the standard data annotation validations. For example, as it attempts to write a record to the database it checks that no other record exists with the same email address. Certain types of validation can't reliably happen at the client, particularly where race conditions could produce a bad result.
The API controller returns a ValidationProblem result to the client, and Postman shows the body of the result as:
{
"type": "https://tools.ietf.org/html/rfc7231#section-6.5.1",
"title": "One or more validation errors occurred.",
"status": 400,
"traceId": "|f06d4ffe-4aa836b5b3f4c9ae.",
"errors": {
"Email": [
"The email address already exists."
]
}
}
Note that the validation error is in the "errors" array in the JSON.
Back in the Blazor Client application, I have the typical HandleValidSubmit function that posts the data to the API and receives a response, as shown here:
private async void HandleValidSubmit()
{
var response = await Http.PostAsJsonAsync<TestModel>("api/Test", testModel);
if (response.StatusCode != System.Net.HttpStatusCode.Created)
{
// How to handle server-side validation errors?
}
}
My question is, how to best process server-side validation errors? The user experience ought to be the same as any other validation error, with the field highlighted, the validation message shown, and the summary at the top of the page.
I ended up solving this by creating a ServerValidator component. I'll post the code here in case it is helpful for others seeking a solution to the same problem.
This code assumes you are calling a Web API endpoint that returns a ValidationProblem result if there are issues.
public class ServerValidator : ComponentBase
{
[CascadingParameter]
EditContext CurrentEditContext { get; set; }
protected override void OnInitialized()
{
base.OnInitialized();
if (this.CurrentEditContext == null)
{
throw new InvalidOperationException($"{nameof(ServerValidator)} requires a cascading " +
$"parameter of type {nameof(EditContext)}. For example, you can use {nameof(ServerValidator)} " +
$"inside an EditForm.");
}
}
public async void Validate(HttpResponseMessage response, object model)
{
var messages = new ValidationMessageStore(this.CurrentEditContext);
if (response.StatusCode == HttpStatusCode.BadRequest)
{
var body = await response.Content.ReadAsStringAsync();
var validationProblemDetails = JsonSerializer.Deserialize<ValidationProblemDetails>(body);
if (validationProblemDetails.Errors != null)
{
messages.Clear();
foreach (var error in validationProblemDetails.Errors)
{
var fieldIdentifier = new FieldIdentifier(model, error.Key);
messages.Add(fieldIdentifier, error.Value);
}
}
}
CurrentEditContext.NotifyValidationStateChanged();
}
// This is to hold the response details when the controller returns a ValidationProblem result.
private class ValidationProblemDetails
{
[JsonPropertyName("status")]
public int? Status { get; set; }
[JsonPropertyName("title")]
public string Title { get; set; }
[JsonPropertyName("type")]
public string Type { get; set; }
[JsonPropertyName("errors")]
public IDictionary<string, string[]> Errors { get; set; }
}
}
To use this new component, you will need to add the component within your EditForm:
<EditForm Model="agency" OnValidSubmit="HandleValidSubmit">
<ServerValidator #ref="serverValidator" />
<ValidationSummary />
... put all your form fields here ...
</EditForm>
Lastly, you can kick off the validation in your #code section:
#code {
private TestModel testModel = new TestModel();
private ServerValidator serverValidator;
private async void HandleValidSubmit()
{
var response = await Http.PostAsJsonAsync<TestModel>("api/TestModels", testModel);
if (response.StatusCode != System.Net.HttpStatusCode.Created)
{
serverValidator.Validate(response, testModel);
}
else
{
Navigation.NavigateTo(response.Headers.Location.ToString());
}
}
}
In theory, this ought to allow you to bypass client validation entirely and rely on your Web API to do it. In practice, I found that Blazor performs client validation when there are annotations on your model, even if you don't include a <DataAnnotationsValidator /> in your form. However, it will still catch any validation issues at the server and return them to you.
how to best process server-side validation errors? The user experience ought to be the same as any other validation error, with the field highlighted, the validation message shown, and the summary at the top of the page.
I don't know what comes in your response, so I made a generic version of a component that do what you need.
Get the CascadingParameter of the EditContext
[CascadingParameter]
public EditContext EditContext { get; set; }
Have a ValidationMessageStore to hold the errors and a function that will display the errors
private ValidationMessageStore _messageStore;
private EventHandler<ValidationRequestedEventArgs> OnValidationRequested => (s, e) =>
{
_messageStore.Clear();
};
private EventHandler<FieldChangedEventArgs> OnFieldChanged => (s, e) =>
{
_messageStore.Clear(e.FieldIdentifier);
};
protected override void OnInitialized()
{
base.OnInitialized();
if (EditContext != null)
{
_messageStore = new ValidationMessageStore(EditContext);
EditContext.OnFieldChanged += OnFieldChanged;
EditContext.OnValidationRequested += OnValidationRequested;
}
}
public override void Dispose()
{
base.Dispose();
if (EditContext != null)
{
EditContext.OnFieldChanged -= OnFieldChanged;
EditContext.OnValidationRequested -= OnValidationRequested;
}
}
private void AddFieldError(ERROR_CLASS_YOU_ARE_USING validatorError)
{
_messageStore.Add(EditContext.Field(validatorError.FIELD_NAME), validatorError.ERROR_MESSAGE);
}
Call the function of the component using it's ref
private async void HandleValidSubmit()
{
var response = await Http.PostAsJsonAsync<TestModel>("api/Test", testModel);
if (response.StatusCode != System.Net.HttpStatusCode.Created)
{
// How to handle server-side validation errors?
// You could also have a foreach or a function that receives an List for multiple fields error display
MyHandleErrorComponent.AddFieldError(response.ERROR_PROPERTY);
}
}
https://learn.microsoft.com/en-us/aspnet/core/blazor/forms-validation has an example of how to handle server-side validation errors:
private async Task HandleValidSubmit(EditContext editContext)
{
customValidator.ClearErrors();
try
{
var response = await Http.PostAsJsonAsync<Starship>(
"StarshipValidation", (Starship)editContext.Model);
var errors = await response.Content
.ReadFromJsonAsync<Dictionary<string, List<string>>>();
if (response.StatusCode == HttpStatusCode.BadRequest &&
errors.Count() > 0)
{
customValidator.DisplayErrors(errors);
}
else if (!response.IsSuccessStatusCode)
{
throw new HttpRequestException(
$"Validation failed. Status Code: {response.StatusCode}");
}
else
{
disabled = true;
messageStyles = "color:green";
message = "The form has been processed.";
}
}
catch (AccessTokenNotAvailableException ex)
{
ex.Redirect();
}
catch (Exception ex)
{
Logger.LogError("Form processing error: {Message}", ex.Message);
disabled = true;
messageStyles = "color:red";
message = "There was an error processing the form.";
}
}
Use two phase validation.
Hook up an event for when the email is entered which calls an "IsEmailUnique" method on your api. This offers your user real time validation information. Perhaps disable the "Save" button until the email has been validated on the server.
You can then handle the Bad Request as you would any other server-side errors.
I am trying to post objects to my server but the received objects have the value null.
Backend Code:
// Signature
public IActionResult Save(string num, string pat, string token, [FromBody]DataCl data, [FromBody]List<items> listItems)
// EDIT: Added class
public class Object
{
public List<items> listItems { get; set; }
public DataCl data { get; set; }
}
// So new signature
public IActionResult Save(string num, string pat, string token, [FromBody]Test test)
// The value is still null
Frontend Code:
post(num, data, list)
return this.http.post<any>(url,{data, list}, httpOptions).subscribe()
So the parameter num, pat and token are receiving the correct data but the data representing the body are not reciving any data - they are null.
With only one object it is working fine - the correct object was received but with two it does not work anymore but why? Is it something in the frontend code? Or backend?
Check the following article here
Don't apply [FromBody] to more than one parameter per action method.
The ASP.NET Core runtime delegates the responsibility of reading the
request stream to the input formatter. Once the request stream is
read, it's no longer available to be read again for binding other
[FromBody] parameters.
You cannot have two FromBody attributes. The from body is only read once.
{data, list} is one object anyway in javascript. There is no way to Post multiple objects in body, unless they are embedded.
{
object1: {}
object2: {}
}
And in you backend code:
class WrapperObjectResponse {
public Object1 = ...
public Object2 = ...
}
In your new signature, try this:
[Route("save/{num}/{pat}/{token}")]
public IActionResult Save(string num, string pat, string token, [FromBody]Test test)
And call like this:
return this.http.post<any>(url + '/' + num + '/' + pat + '/' + token + '/',{data: {}, list = []}, httpOptions).subscribe()
I want to know exactly why this is not working:
[HttpPost]
public IHttpActionResult Post(Slack_Webhook json)
{
return Ok(json.challenge);
}
public class Slack_Webhook
{
public string type { get; set; }
public string token { get; set; }
public string challenge { get; set; }
}
The Official Documentation says:
We’ll send HTTP POST requests to this URL when events occur. As soon
as you enter a URL, we’ll send a request with a challenge parameter,
and your endpoint must respond with the challenge value.
This is an example object (JSON) sent by Slack:
{
"token": "Jhj5dZrVaK7ZwHHjRyZWjbDl",
"challenge": "3eZbrw1aBm2rZgRNFdxV2595E9CY3gmdALWMmHkvFXO7tYXAYM8P",
"type": "url_verification"
}
EDIT:
I could write a book on code that does not work in this issue... here's another example that did not work - still no idea what is wrong:
[HttpPost]
public IHttpActionResult Post()
{
var pairs = Request.GetQueryNameValuePairs();
bool isValidToken = false;
string c = "This does not work.";
foreach(var pair in pairs)
{
if (pair.Key == "token")
{
if (pair.Value == "<UNIQUETOKEN>")
{
isValidToken = true;
}
}
if (pair.Key == "challenge")
{
c = pair.Value;
}
}
if (isValidToken == true)
{
return Json(new {challenge = c });
}
else
{
return BadRequest();
}
}
EDIT2:
Very interesting that I get NULL as a response from below code - that means the body of the received POST is empty.. Could anyone with a working Slack-Integration try that out? So their site is wrong, stating the challenge is sent in the body - where else could it be?
// POST: api/Slack
[HttpPost]
public IHttpActionResult Post([FromBody]string json)
{
return Json(json);
}
EDIT3:
This function is used to get the raw request, but there is nothing inside the body - I am out of solutions.. the support of Slack said, they have no idea about ASP.NET and I should ask here on SO for a solution. Here we are again! ;-)
[HttpPost]
public async Task<IHttpActionResult> ReceivePostAsync()
{
string rawpostdata = await RawContentReader.Read(this.Request);
return Json(new StringContent( rawpostdata));
}
public class RawContentReader
{
public static async Task<string> Read(HttpRequestMessage req)
{
using (var contentStream = await req.Content.ReadAsStreamAsync())
{
contentStream.Seek(0, SeekOrigin.Begin);
using (var sr = new StreamReader(contentStream))
{
return sr.ReadToEnd();
}
}
}
}
The result ( as expected ) looks like this:
Our Request:
POST
"body": {
"type": "url_verification",
"token": "<token>",
"challenge": "<challenge>"
}
Your Response:
"code": 200
"error": "challenge_failed"
"body": {
{"Headers":[{"Key":"Content-Type","Value":["text/plain; charset=utf-8"]}]}
}
I think I'm missing something - is there another way to get the body of the POST-Request? I mean, I can get everything else - except the body ( or it says it is empty).
EDIT4:
I tried to read the body with another function I found - without success, returns empty string - but to let you know what I already tried, here it is:
[HttpPost]
public IHttpActionResult ReceivePost()
{
var bodyStream = new
StreamReader(HttpContext.Current.Request.InputStream);
bodyStream.BaseStream.Seek(0, SeekOrigin.Begin);
var bodyText = bodyStream.ReadToEnd();
return Json(bodyText);
}
While trying to solve this I learnt a lot - but this one seems to be so impossible, that I think I will never solve it alone. Thousands of tries with thousands of different functions - I have tried hundreds of parameters and functions in all of WebApi / ASP.NET / MVC / whatever - why is there no BODY? Does it exist? What's his/her name? Where does it live? I really wanna hang out with that parameter if I ever find it, must be hidden at the end of the rainbow under a pot of gold.
If you can use ASP.NET Core 2, this will do the trick:
public async Task<ActionResult> HandleEvent([FromBody] dynamic data)
=> new ContentResult {Content = data.challenge};
According to the official documentation linked to in the OP you have to format your response depending on the content type you return.
It is possible you are not returning the value (challenge) in one of the expected formats.
Once you receive the event, respond in plaintext with the challenge
attribute value. In this example, that might be:
HTTP 200 OK
Content-type: text/plain
3eZbrw1aBm2rZgRNFdxV2595E9CY3gmdALWMmHkvFXO7tYXAYM8P
To do the above you would have needed to return your request differently
[HttpPost]
public IHttpActionResult Post([FromBody]Slack_Webhook json) {
//Please verify that the token value found in the payload
//matches your application's configured Slack token.
if (ModelState.IsValid && json != null && ValidToken(json.token)) {
var response = Request.CreateResponse(HttpStatusCode.OK, json.challenge, "text/plain");
return ResponseMessage(response);
}
return BadRequest();
}
Documentation also shows
Or even JSON:
HTTP 200 OK
Content-type: application/json
{"challenge":"3eZbrw1aBm2rZgRNFdxV2595E9CY3gmdALWMmHkvFXO7tYXAYM8P"}
Which again would have to be formatted a little differently
[HttpPost]
public IHttpActionResult Post([FromBody]Slack_Webhook json) {
//Please verify that the token value found in the payload
//matches your application's configured Slack token.
if (ModelState.IsValid && json != null && ValidToken(json.token)) {
var model = new { challenge = json.challenge };
return Ok(model);
}
return BadRequest();
}
Here's how you can access the data:
[HttpPost]
[Route("something")]
public JsonResult DoSomething()
{
var token = HttpContext.Request.Form["token"];
// Is the same as:
// var token = Request.Form["token"];
return new JsonResult(token);
}
I suggest using a Request Bin for further debugging.
this is my post method in apiController
[HttpPost]
public String Post([FromBody]String key)
{
Users ws;
try
{
ws = JsonConvert.DeserializeObject<Users>(key);
// return "success "+ key;
return db.InsertFineInfo(ws);
}
catch (Exception ex)
{
return "ERROR Testing Purposes: " + ex;
}
}
This is part of my model calss.(Users class)there are many attributes but here i have mentioned only few of em with getters and setters
{
private String UserID;
private String UserName;
private String UserHeight;
private String UserWeight;
private String UserBMI;
private String RequiredNeutrition;
public string UserID1
{
get
{
return UserID;
}
set
{
UserID = value;
}
}
i tried to call this post method using postmen .in every attempt i get a null value for key .
this is how i tried the post method with one header parameter application/json
what went wrong ? something wrong with method or the way i try to call it?
OK a couple points...
Firstly the JSON your method would be expecting would look like
{
"key": "your string....."
}
Secondly the code you have supplied is a bit counter intuitive... Why not simply have
[HttpPost]
public String Post([FromBody]Users ws)
{
... // Done ?
}
You need to publish more code for me to be able to give you a correct answer as to what the JSON would look like that would be accepted by the above method.
In Web API when the parameter comes through as null you can be pretty sure that the JSON sent to the method does not match the JSON generated when you serialize the parameter to a JSON string.
You have to model your input as a C# class, and then take that type as an input.
Assuming that you already have a "User" class, with the same properties as the JSON, that you send in the request body:
[HttpPost]
public String Post([FromBody]User user)
{
try
{
return db.InsertFineInfo(user);
}
catch (Exception ex)
{
return "ERROR Testing Purposes: " + ex;
}
}
this opportunity Ii'd like to thank everyone who has an answer to this question, I'm trying to get a json from my web api service and I can't this is my code at the web api...
[ResponseType(typeof(List<CompanyType>))]
[Route("GetList")]
[DeflateCompression]
public async Task<IHttpActionResult> Get()
{
List<CompanyType> companyTypes = (List<CompanyType>)MemoryCacheManager.GetValue(#"CompanyTypes");
if (companyTypes != null) return Ok(companyTypes);
companyTypes = await _CompanyType.Queryable().ToListAsync();
if (companyTypes == null) return Ok(HttpStatusCode.NoContent);
MemoryCacheManager.Add(#"CompanyTypes", companyTypes);
return Ok(companyTypes);
}
and at the site of my client I got this
public async Task<T> GetAsync<T>(string action, string authToken = null)
{
using (var client = new HttpClient())
{
if (!authToken.IsNullOrWhiteSpace())
client.DefaultRequestHeaders.Authorization = AuthenticationHeaderValue.Parse(#"Bearer " + authToken);
var result = await client.GetAsync(BuildActionUri(action));
string json = await result.Content.ReadAsStringAsync();
if (result.IsSuccessStatusCode)
return JsonConvert.DeserializeObject<T>(json); //This line fails because the characters in the value
throw new ApiException(result.StatusCode, json);
}
}
As you can see there nothing than weird here it is a simple code that try to parse a json value to a Generic class but this fails bacause when i call my webapi Url it gives me this value
json = ��VR�LQ�R2T�Q�2 u�B* R�"E�e�)�#q�������̔Ԣb%��Ҝ�Z�>#�>#�>�̊B������J�r2�q�
I don't know why my webapi give me tha value, when I try to debug just my service it give me this value
<ArrayOfCompanyType xmlns:i="http://www.w3.org/2001/XMLSchema-instance" ><CompanyType z:Id="i1" xmlns:z="http://schemas.microsoft.com/2003/10/Serialization/"><Id>1</Id><Type>Privada</Type><JobProviders i:nil="true" /></CompanyType><CompanyType z:Id="i2" xmlns:z="http://schemas.microsoft.com/2003/10/Serialization/"><Id>2</Id><Type>Mixta</Type><JobProviders i:nil="true" /></CompanyType><CompanyType z:Id="i3" xmlns:z="http://schemas.microsoft.com/2003/10/Serialization/"><Id>3</Id><Type>Publica</Type><JobProviders i:nil="true" /></CompanyType></ArrayOfCompanyType>
as you can see everything looks fine but the problem start when I try to parse to get this value from my client.
this is my class
[DataContract(IsReference = true, Name = #"CompanyType", )]
public class CompanyType : Entity
{
[DataMember(Order = 0)]
public int Id { get; set; }
[DataMember(Order = 1)]
public string Type { get; set; }
[DataMember(Order = 2)]
public virtual List<JobProvider> JobProviders { get; set; }
}
I tried it without de DataContracts and still the same error.
best regards!.
Well I figured out, I was trying to use this sample http://blog.developers.ba/asp-net-web-api-gzip-compression-actionfilter/ but the thing was that the serializer wasn´t registered, so at my startup project I did this
GlobalConfiguration.Configuration.Formatters.Add(new ProtoBufFormatter());
And I changed my Actions deleting the attribute [DeflateCompression]
[ResponseType(typeof(List<CompanyType>))]
[Route("GetList")]
//[DeflateCompression]
public async Task<IHttpActionResult> Get()
{
Logic goes here....
}
And It's working now, but now I have another Issue and its when I try to make a call to my webapi action where I have to response an IHttpActionResult there is an exception of
no serializer defined for type: System.Object