NSwag: 404 Not Found /swagger/v1/swagger.json on IIS

Question

I have a basic asp.net core 2.1 web API. I installed NSwag.ASPNetCore nuget package.

here is my startup.cs. When I run this on IIS Express, swagger is working fine. Once I deploy this to IIS, I am getting 404 not found. Do I need to add a Path somewhere?

    public void ConfigureServices(IServiceCollection services)
    {
        services.AddCors(o => o.AddPolicy("CorsPolicy", builder =>
        {
            builder.AllowAnyOrigin()
                .AllowAnyMethod()
                .AllowAnyHeader();
        }));

        services.AddMvc();
        // Add framework services.
        services.AddMvc()
            .AddJsonOptions(options =>
            {
                options.SerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();
                options.SerializerSettings.NullValueHandling = Newtonsoft.Json.NullValueHandling.Ignore;
            }).SetCompatibilityVersion(CompatibilityVersion.Version_2_1);

        //Add Application Services
        services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
        services.AddSwaggerDocument();

    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public void Configure(IApplicationBuilder app, IHostingEnvironment env)
    {
        app.UseCors("CorsPolicy");

        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }

        app.UseSwagger();
        app.UseSwaggerUi3();
        app.UseMvc();
    }
}

How did you deploy to IIS? Try to enable [Log creation and redirection](https://learn.microsoft.com/en-us/aspnet/core/host-and-deploy/aspnet-core-module?view=aspnetcore-2.2#log-creation-and-redirection) — Edward, Mar 08 '19 at 02:11

Dutch Nico · Answer 1 · 2019-07-21T09:37:59.913

1

As mentioned by Rico below: upgrading to nswag v13 should fix the issue (for me it worked).

For versions of nswag before v13:

I had the same problem and I found a solution here: NSwag Issue #1914 What you need to do is configure a 'transform to external path':

app.UseSwaggerUi3(config =>
{
    config.TransformToExternalPath = (s, r) =>
    {
        string path = s.EndsWith("swagger.json") && !string.IsNullOrEmpty(r.PathBase)
            ? $"{r.PathBase}{s}"
            : s;
        return path;
    };
});

This worked for me on my iisexpress and on iis.

edited Jul 21 '19 at 09:37

answered Jun 03 '19 at 18:08

Dutch Nico

250
2
8

With NSwag v13 this hopefully just works without any changes, see https://github.com/RicoSuter/NSwag/pull/2196 – Rico Suter Jun 11 '19 at 20:49
Thanks, I've tried it and I have modified my answer. – Dutch Nico Jul 21 '19 at 09:38

score 0 · Answer 2 · answered Jun 24 '19 at 08:10

0

Check if you do not use Virtual Path for the application. Swagger by default checks absolute path instead of localhost:port/MyVirtualPath/swagger/v1/swagger.json

It may happen when you use IIS server with virtual path delimiter.

answered Jun 24 '19 at 08:10

J.Wincewicz

849
12
19

NSwag: 404 Not Found /swagger/v1/swagger.json on IIS

2 Answers2