MVC WebAPI 调用一次且仅一次

Question

I have a WebAPI deployed as a Azure Web App It is .net Framework 4.6.2. I can call it it once (from a variety of sources, including my JavaScript code and Postman) but the second time it gets called I get the following error:

{ "Message": "The request contains an entity body but no Content-Type header. The inferred media type 'application/octet-stream' is not supported for this resource.", "ExceptionMessage": "No MediaTypeFormatter is available to read an object of type 'ImportSourceLineActionRequest' from content with media type 'application/octet-stream'.", "ExceptionType": "System.Net.Http.UnsupportedMediaTypeException", "StackTrace": " at System.Net.Http.HttpContentExtensions.ReadAsAsync[T](HttpContent content, Type type, IEnumerable 1 formatters, IFormatterLogger formatterLogger, CancellationToken cancellationToken) at System.Web.Http.ModelBinding.FormatterParameterBinding.ReadContentAsync(HttpRequestMessage request, Type type, IEnumerable`1 formatters, IFormatterLogger formatterLogger, CancellationToken cancellationToken)" }

Some things to note:

• The Content-Type is set in Postman to "application/json"
• The Content-Type is set in my JavaScript to "application/json"

So... why does my webservice suddenly think I am sending application/octet-stream?

Further, rebooting the Web App fixes the issue... for one more time.

Javascript code making the call:

 const resp = await fetch(callUrl, { method: 'POST', body: bodyOjbectStr, headers: { 'Accept': 'application/json', 'Content-Type': 'application/json' } });

API Method that is getting called

[HttpPost]
public void DoSomeWork(DoSomeWorkRequestRequest request)
{
    // Do various things
}

WebApiConfig.cs (snippet of)

public static class WebApiConfig
    {
        public static void Register(HttpConfiguration config)
        {
            // Web API configuration and services
            // config.Filters.Add(new RequireHttpsAttribute());

            // Web API routes
            config.MapHttpAttributeRoutes();

            config.Routes.MapHttpRoute(
                name: "DefaultApi",
                routeTemplate: "{controller}/{action}/{id}",
                defaults: new { id = RouteParameter.Optional }
            );

            var appXmlType = config.Formatters.XmlFormatter.SupportedMediaTypes.FirstOrDefault(t => t.MediaType == "application/xml");
            config.Formatters.XmlFormatter.SupportedMediaTypes.Remove(appXmlType);

            GlobalConfiguration.Configuration.Formatters.JsonFormatter.MediaTypeMappings.Add(new System.Net.Http.Formatting.RequestHeaderMapping("Accept","text/html",StringComparison.InvariantCultureIgnoreCase,true,"application/json"));
        }
    }

Any help gratefully accepted.

DS

Answer 1

For completeness, this problem got solved. It turned out to be a problem with the 2FA we were using. Not sure why it ever worked once and failed the second time, but when IT made some adjustments to 2FA it all worked.