I am trying to use a Refit client against a method in a ASP.NET 6 controller that returns Bson. The method looks like this:
[Produces("application/bson", Type=typeof(MyDto))]
public async Task<IActionResult> GetBinaryDataAsBson(Guid id)
In the project there is a class BsonMediaTypeFormatter that use Newtonsoft BsonDataWriter to write BSON.
public override Task WriteResponseBodyAsync(OutputFormatterWriteContext context)
{
var response = context.HttpContext.Response;
using (var ms = new MemoryStream())
{
using (var bsonWriter = new BsonDataWriter(ms) { CloseOutput = false })
{
var jsonSerializer = JsonSerializer.Create(_jsonSerializerSettings);
jsonSerializer.Serialize(bsonWriter, context.Object);
bsonWriter.Flush();
}
return response.Body.WriteAsync(ms.GetBuffer(), 0, (int)ms.Length);
}
}
When I try the client returns null for Content.
It works if I change application/bson to json in the Produces attribute.
Does anyone know how make Refit work with BSON?
Related
If I am sending JSON data (via POST) to a .Net Core Web API like this
{ a: "a", b: "b" }
What do I need to do to have a controller method like this?
[HttpPost]
public async Task SometMethod(string a, string b)
{
return Ok();
}
Normally, all tutorials and docs say that you need to define a class and use [FromBody] attribute. But how can I make do without extra classes that I don't really need?
Firstly,your json should be:
{
"a":"a",
"b":"b"
}
You could receive data as JObject instead of a class like below:
[Route("api/[controller]")]
[ApiController]
public class ValuesController : ControllerBase
{
[HttpPost]
public void Post(JObject data)
{
//get the property value like below
var data1 = data["a"].ToString();
var data2 = data["b"].ToString();
}
}
Result (For easily distinguish value and property name,I change a to aaa and b to bbb):
If you want to post the data to the method like this, you will have to serialize your data before you can send it to the server. Assuming you are using JQuery, you can do like the following.
var postData = $.param({ a: "a", b: "b" });
//Then you can send this postData obejct to the server. This should perfectly bound to the parameters.
You can also use the same in an angular app.
After some research I came up with ModelBinder to do just this. It is not performant since it re-parses the whole request body for every parameter. I will improve it in the future.
https://github.com/egorpavlikhin/JsonParametersModelBinder
public class JsonBinder : IModelBinder
{
public async Task BindModelAsync(ModelBindingContext bindingContext)
{
if (bindingContext == null) throw new ArgumentNullException(nameof(bindingContext));
var actionDescriptor = bindingContext.ActionContext.ActionDescriptor as ControllerActionDescriptor;
if (actionDescriptor.MethodInfo.GetCustomAttributes(typeof(JsonParametersAttribute), false).Length > 0)
{
var context = bindingContext.HttpContext;
if (context.Request.ContentType != "application/json")
{
bindingContext.Result = ModelBindingResult.Failed();
return;
}
#if (NETSTANDARD2_1 || NETCOREAPP3_0)
context?.Request.EnableBuffering();
#else
context?.Request.EnableRewind();
#endif
using var reader = new StreamReader(context.Request.Body, Encoding.UTF8,
false,
1024,
true); // so body can be re-read next time
var body = await reader.ReadToEndAsync();
var json = JsonSerializer.Deserialize<Dictionary<string, JsonElement>>(body);
if (json.TryGetValue(bindingContext.FieldName, out var value))
{
if (bindingContext.ModelType == typeof(string))
{
bindingContext.Result = ModelBindingResult.Success(value.GetString());
}
else if (bindingContext.ModelType == typeof(object))
{
var serializerOptions = new JsonSerializerOptions
{
Converters = {new DynamicJsonConverter()}
};
var val = JsonSerializer.Deserialize<dynamic>(value.ToString(), serializerOptions);
bindingContext.Result = ModelBindingResult.Success(val);
}
}
context.Request.Body.Position = 0; // rewind
}
}
}
I'm using Asp.Net Core as a Rest Api Service.
I need access to request and response in ActionFilter. Actually, I found the request in OnActionExcecuted but I can't read the response result.
I'm trying to return value as follow:
[HttpGet]
[ProducesResponseType(typeof(ResponseType), (int)HttpStatusCode.OK)]
[Route("[action]")]
public async Task<IActionResult> Get(CancellationToken cancellationToken)
{
var model = await _responseServices.Get(cancellationToken);
return Ok(model);
}
And in ActionFilter OnExcecuted method as follow:
_request = context.HttpContext.Request.ReadAsString().Result;
_response = context.HttpContext.Response.ReadAsString().Result; //?
I'm trying to get the response in ReadAsString as an Extension method as follow:
public static async Task<string> ReadAsString(this HttpResponse response)
{
var initialBody = response.Body;
var buffer = new byte[Convert.ToInt32(response.ContentLength)];
await response.Body.ReadAsync(buffer, 0, buffer.Length);
var body = Encoding.UTF8.GetString(buffer);
response.Body = initialBody;
return body;
}
But, there is no result!
How I can get the response in OnActionExcecuted?
Thanks, everyone for taking the time to try and help explain
If you're logging for json result/ view result , you don't need to read the whole response stream. Simply serialize the context.Result:
public class MyFilterAttribute : ActionFilterAttribute
{
private ILogger<MyFilterAttribute> logger;
public MyFilterAttribute(ILogger<MyFilterAttribute> logger){
this.logger = logger;
}
public override void OnActionExecuted(ActionExecutedContext context)
{
var result = context.Result;
if (result is JsonResult json)
{
var x = json.Value;
var status = json.StatusCode;
this.logger.LogInformation(JsonConvert.SerializeObject(x));
}
if(result is ViewResult view){
// I think it's better to log ViewData instead of the finally rendered template string
var status = view.StatusCode;
var x = view.ViewData;
var name = view.ViewName;
this.logger.LogInformation(JsonConvert.SerializeObject(x));
}
else{
this.logger.LogInformation("...");
}
}
I know there is already an answer but I want to also add that the problem is the MVC pipeline has not populated the Response.Body when running an ActionFilter so you cannot access it. The Response.Body is populated by the MVC middleware.
If you want to read Response.Body then you need to create your own custom middleware to intercept the call when the Response object has been populated. There are numerous websites that can show you how to do this. One example is here.
As discussed in the other answer, if you want to do it in an ActionFilter you can use the context.Result to access the information.
For logging whole request and response in the ASP.NET Core filter pipeline you can use Result filter attribute
public class LogRequestResponseAttribute : TypeFilterAttribute
{
public LogRequestResponseAttribute() : base(typeof(LogRequestResponseImplementation)) { }
private class LogRequestResponseImplementation : IAsyncResultFilter
{
public async Task OnResultExecutionAsync(ResultExecutingContext context, ResultExecutionDelegate next)
{
var requestHeadersText = CommonLoggingTools.SerializeHeaders(context.HttpContext.Request.Headers);
Log.Information("requestHeaders: " + requestHeadersText);
var requestBodyText = await CommonLoggingTools.FormatRequestBody(context.HttpContext.Request);
Log.Information("requestBody: " + requestBodyText);
await next();
var responseHeadersText = CommonLoggingTools.SerializeHeaders(context.HttpContext.Response.Headers);
Log.Information("responseHeaders: " + responseHeadersText);
var responseBodyText = await CommonLoggingTools.FormatResponseBody(context.HttpContext.Response);
Log.Information("responseBody: " + responseBodyText);
}
}
}
In Startup.cs add
app.UseMiddleware<ResponseRewindMiddleware>();
services.AddScoped<LogRequestResponseAttribute>();
Somewhere add static class
public static class CommonLoggingTools
{
public static async Task<string> FormatRequestBody(HttpRequest request)
{
//This line allows us to set the reader for the request back at the beginning of its stream.
request.EnableRewind();
//We now need to read the request stream. First, we create a new byte[] with the same length as the request stream...
var buffer = new byte[Convert.ToInt32(request.ContentLength)];
//...Then we copy the entire request stream into the new buffer.
await request.Body.ReadAsync(buffer, 0, buffer.Length).ConfigureAwait(false);
//We convert the byte[] into a string using UTF8 encoding...
var bodyAsText = Encoding.UTF8.GetString(buffer);
//..and finally, assign the read body back to the request body, which is allowed because of EnableRewind()
request.Body.Position = 0;
return $"{request.Scheme} {request.Host}{request.Path} {request.QueryString} {bodyAsText}";
}
public static async Task<string> FormatResponseBody(HttpResponse response)
{
//We need to read the response stream from the beginning...
response.Body.Seek(0, SeekOrigin.Begin);
//...and copy it into a string
string text = await new StreamReader(response.Body).ReadToEndAsync();
//We need to reset the reader for the response so that the client can read it.
response.Body.Seek(0, SeekOrigin.Begin);
response.Body.Position = 0;
//Return the string for the response, including the status code (e.g. 200, 404, 401, etc.)
return $"{response.StatusCode}: {text}";
}
public static string SerializeHeaders(IHeaderDictionary headers)
{
var dict = new Dictionary<string, string>();
foreach (var item in headers.ToList())
{
//if (item.Value != null)
//{
var header = string.Empty;
foreach (var value in item.Value)
{
header += value + " ";
}
// Trim the trailing space and add item to the dictionary
header = header.TrimEnd(" ".ToCharArray());
dict.Add(item.Key, header);
//}
}
return JsonConvert.SerializeObject(dict, Formatting.Indented);
}
}
public class ResponseRewindMiddleware {
private readonly RequestDelegate next;
public ResponseRewindMiddleware(RequestDelegate next) {
this.next = next;
}
public async Task Invoke(HttpContext context) {
Stream originalBody = context.Response.Body;
try {
using (var memStream = new MemoryStream()) {
context.Response.Body = memStream;
await next(context);
//memStream.Position = 0;
//string responseBody = new StreamReader(memStream).ReadToEnd();
memStream.Position = 0;
await memStream.CopyToAsync(originalBody);
}
} finally {
context.Response.Body = originalBody;
}
}
You can also do...
string response = "Hello";
if (result is ObjectResult objectResult)
{
var status = objectResult.StatusCode;
var value = objectResult.Value;
var stringResult = objectResult.ToString();
responce = (JsonConvert.SerializeObject(value));
}
I used this in a .net core app.
Hope it helps.
Is there any way to implement #Html.Action method in ASP.NET Core (like it was in ASP.NET MVC)? I know about the ViewComponent feature of ASP.NET Core. But there is a scenario when we have to use Action method.
This is the way to implement this as a HtmlHelper extension.
You can use it as follows:
The last parameter is an anonymous type.
#Html.Action("Action");
#Html.Action("Action", new { string a = "a", int i = 5 }
#Html.Action("Action", "Controller");
#Html.Action("Action", "Controller", new (string a = "a", int i = 5 }
using System;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Html;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc.Infrastructure;
using Microsoft.AspNetCore.Routing;
namespace Microsoft.AspNetCore.Mvc.Rendering
{
public static class HtmlHelperViewExtensions
{
public static IHtmlContent Action(this IHtmlHelper helper, string action, object parameters = null)
{
var controller = (string)helper.ViewContext.RouteData.Values["controller"];
return Action(helper, action, controller, parameters);
}
public static IHtmlContent Action(this IHtmlHelper helper, string action, string controller, object parameters = null)
{
var area = (string)helper.ViewContext.RouteData.Values["area"];
return Action(helper, action, controller, area, parameters);
}
public static IHtmlContent Action(this IHtmlHelper helper, string action, string controller, string area, object parameters = null)
{
if (action == null)
throw new ArgumentNullException(nameof(controller));
if (controller == null)
throw new ArgumentNullException(nameof(action));
var task = ActionAsync(helper, action, controller, area, parameters);
return task.Result;
}
private static async Task<IHtmlContent> ActionAsync(this IHtmlHelper helper, string action, string controller, string area, object parameters = null)
{
// fetching required services for invocation
var currentHttpContext = helper.ViewContext.HttpContext;
var httpContextFactory = GetServiceOrFail<IHttpContextFactory>(currentHttpContext);
var actionInvokerFactory = GetServiceOrFail<IActionInvokerFactory>(currentHttpContext);
var actionSelector = GetServiceOrFail<IActionDescriptorCollectionProvider>(currentHttpContext);
// creating new action invocation context
var routeData = new RouteData();
var routeParams = new RouteValueDictionary(parameters ?? new { });
var routeValues = new RouteValueDictionary(new { area, controller, action });
var newHttpContext = httpContextFactory.Create(currentHttpContext.Features);
newHttpContext.Response.Body = new MemoryStream();
foreach (var router in helper.ViewContext.RouteData.Routers)
routeData.PushState(router, null, null);
routeData.PushState(null, routeValues, null);
routeData.PushState(null, routeParams, null);
var actionDescriptor = actionSelector.ActionDescriptors.Items.First(i => i.RouteValues["Controller"] == controller && i.RouteValues["Action"] == action);
var actionContext = new ActionContext(newHttpContext, routeData, actionDescriptor);
// invoke action and retreive the response body
var invoker = actionInvokerFactory.CreateInvoker(actionContext);
string content = null;
await invoker.InvokeAsync().ContinueWith(task =>
{
if (task.IsFaulted)
{
content = task.Exception.Message;
}
else if (task.IsCompleted)
{
newHttpContext.Response.Body.Position = 0;
using (var reader = new StreamReader(newHttpContext.Response.Body))
content = reader.ReadToEnd();
}
});
return new HtmlString(content);
}
private static TService GetServiceOrFail<TService>(HttpContext httpContext)
{
if (httpContext == null)
throw new ArgumentNullException(nameof(httpContext));
var service = httpContext.RequestServices.GetService(typeof(TService));
if (service == null)
throw new InvalidOperationException($"Could not locate service: {nameof(TService)}");
return (TService)service;
}
}
}
While it does work and renders the content correctly, when you try to access the IHttpContextAccessor.HttpContext property afterwards it is empty for some reason. I.e. you are opening another controller method which has a reference to IHttpContextAccessor via dependency injection and try to access the HttpContext property after you have renderend an Html.Action-element inside a partial view for example. If I remove the Html.Action-Element, HttpContext is filled correctly. I assume it somehow destroys the context.
If I have this controller:
public class SomeController : ApiController
{
public SomeInfoDto Get()
{
return new SomeInfoDto();
}
}
When I call /api/Some with a get request I will get JSON in the Content Body because JSON.NET has been kind enough to serialise it for me.
However, if I wanted to send a 500 HTTP code and some JSON I thought I could do this:
public HttpResponseMessage Get()
{
return new HttpResponseMessage(HttpStatusCode.InternalServerError)
{
Content = // not sure what to put here
}
}
So I googled to find out what to put for the Content and found this resource
public class JsonContent : HttpContent
{
private readonly JToken _value;
public JsonContent(JToken value)
{
_value = value;
Headers.ContentType = new MediaTypeHeaderValue("application/json");
}
protected override Task SerializeToStreamAsync(Stream stream,
TransportContext context)
{
var jw = new JsonTextWriter(new StreamWriter(stream))
{
Formatting = Formatting.Indented
};
_value.WriteTo(jw);
jw.Flush();
return Task.FromResult<object>(null);
}
protected override bool TryComputeLength(out long length)
{
length = -1;
return false;
}
}
Which I can easily modify to fit my purposes.
However, my question is, if I get SerializeToStreamAsync to use JsonConvert.SerializeObject(_value) further down the Web Api pipeline will it be serialised again?
I have set the GlobalConfiguration.Configuration like this:
var formatters = GlobalConfiguration.Configuration.Formatters;
var jsonFormatter = formatters.JsonFormatter;
var settings = jsonFormatter.SerializerSettings;
settings.Formatting = Formatting.Indented;
settings.ContractResolver = new CamelCasePropertyNamesContractResolver();
My Implementation for the SerializeToStreamAsync is this:
protected override Task SerializeToStreamAsync(Stream stream, TransportContext context)
{
using (var streamWriter = new StreamWriter(stream))
{
streamWriter.WriteAsync(JsonConvert.SerializeObject(this.value)).Wait();
streamWriter.FlushAsync().Wait();
}
return Task.FromResult<object>(null);
}
EDIT: Providing a concrete sample with formatter.
If you want to send JSON content with Http Status Code 500, you can use the extension method HttpRequestMessage.CreateResponse. There is no need for any advanced serialization and formatting. More info on that here.
https://msdn.microsoft.com/en-us/library/system.net.http.httprequestmessageextensions.createresponse%28v=vs.118%29.aspx
Request.CreateResponse(HttpStatusCode.InternalServerError, new string[] { "value1", "value2" }, new JsonMediaTypeFormatter())
(Or)
Request.CreateResponse(HttpStatusCode.InternalServerError, new string[] { "value1", "value2" }, 'application/json')
I have the following action method to perform an API call:-
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Create(Rack rack, FormCollection formValues)
{
if (ModelState.IsValid) {
using (var client = new WebClient())
{
var query = HttpUtility.ParseQueryString(string.Empty);
foreach (string key in formValues)
{
query[key] = this.Request.Form[key];
}
query["username"] = "testuser";
query["password"] = ///.....
query["assetType"] = "Rack";
query["operation"] = "AddAsset";
var url = new UriBuilder("http://win-spdev:8400/servlets/AssetServlet");
url.Query = query.ToString();
try
{
string xml = client.DownloadString(url.ToString());
}
The return XML from the API call looks as follow:-
<operation>
<operationstatus>Failure</operationstatus>
<message>Rack already exists.Unable to add</message>
</operation>
but how i can reach the message and operationstaus and according to them to display an appropriate message . i use to serialize the returned Json such as , but i am not sure how to do so for the xML:-
var serializer = new JavaScriptSerializer();
var myObject = serializer.Deserialize<newprocess>(json);
string activityid = myObject.activityId;
Just load it into an XmlDocument.
Untested and from the top of my head:
var xmlDoc = new XmlDocument();
xmlDoc.LoadXml(theXML);
var status = xmlDoc.SelectSingleNode("/operation/operationstatus").InnerText;
var message = xmlDoc.SelectSingleNode("/operation/message").InnerText;
If you using ASP.NET mvc, I believe you can use HttpClient, instead of WebClient:
Define result class:
public class operation
{
public string operationstatus{get;set;}
public string message{get;set;}
}
And then use it for automatic deserilization:
var client = new HttpClient();
var result = client.PostAsync(url,
new FormUrlEncodedContent(new Dictionary<string, string>{
{"username","testuser"},
{"assetType","Rack"}}))
.Result.Content
.ReadAsAsync<operation>().Result;