How to configure Swagger in Dev/Test and Production environment

Question

I have configured Swagger in my .NET 6 Web API project. In local, I can access Swagger file. Below is my code for that.

 public static void ConfigureSwaggerMiddleware(this WebApplication app)
        {
            if (app.Environment.IsDevelopment())
            {
                app.UseSwagger();
                app.UseSwaggerUI(c =>
                {
                    c.SwaggerEndpoint("/swagger/v1/swagger.yaml", "API V1");
                   
                });
            }
            else
            {
                app.UseSwagger();
                app.UseSwaggerUI(c =>
                {
                    c.SwaggerEndpoint("swagger/v1/swagger.yaml", "API V1");
                    c.RoutePrefix = "api/abc";

                });
            }
        }

Now, I want to configure its URL in dev, test and higher environment like https://devurl/api/abc/swagger.yaml. I am trying above code but I am getting an error as

No webpage was found for the web address: https://localhost:7120/swagger/index.html

@ScottishTapWater updated my question now. I am still having an issue. — niler, Jan 19 '23 at 12:30
Is the issue more that you're wanting to set the whole URL rather than just the swagger endpoint? — ScottishTapWater, Jan 19 '23 at 13:00
So as far as I know, you can't have a totally different URL for Swagger as the rest of your app... You can only change after the first `/` — ScottishTapWater, Jan 19 '23 at 13:35
@ScottishTapWater right. I don't want to set whole new URL. Just want to append api/abc in existing URL. — niler, Jan 19 '23 at 13:40
does `c.SwaggerEndpoint("api/abc/swagger/v1/swagger.yaml", "API V1");` work? — ScottishTapWater, Jan 19 '23 at 13:47
pls correct me if I made the mistake to understand your requirement. — Tiny Wang, Jan 20 '23 at 09:51

score 0 · Answer 1 · answered Jan 20 '23 at 07:15

I'm afraid what you want can't be realized if you only changed the route prefix.

public static IApplicationBuilder UseSwaggerUI(
            this IApplicationBuilder app,
            Action<SwaggerUIOptions> setupAction = null)
        {
            SwaggerUIOptions options;
            using (var scope = app.ApplicationServices.CreateScope())
            {
                options = scope.ServiceProvider.GetRequiredService<IOptionsSnapshot<SwaggerUIOptions>>().Value;
                setupAction?.Invoke(options);
            }

            // To simplify the common case, use a default that will work with the SwaggerMiddleware defaults
            if (options.ConfigObject.Urls == null)
            {
                var hostingEnv = app.ApplicationServices.GetRequiredService<IWebHostEnvironment>();
                options.ConfigObject.Urls = new[] { new UrlDescriptor { Name = $"{hostingEnv.ApplicationName} v1", Url = "v1/swagger.json" } };
            }

            return app.UseSwaggerUI(options);
        }

When we didn't set any config option for use swagger UI, it will set the default URL as v1/swagger.json with the default route prefix public string RoutePrefix { get; set; } = "swagger"; That makes us get the swagger.json file to load the index page. While you changed the route prefix value, it will make your API application failed to find the swagger configuration file, which will make it 404 error.

So we need to change both launchsetting.json and add app.UseSwagger options. I referred to this answer.

Here's my configuration in Program.cs and in launchsetting.json, I changed "launchUrl": "api/abc/swagger".

if (app.Environment.IsDevelopment())
{
    //app.UseSwagger();
    app.UseSwagger(c =>
    {
        c.RouteTemplate = "api/abc/swagger/{documentname}/swagger.json";
    });
    //app.UseSwaggerUI();
    app.UseSwaggerUI(c =>
    {
        c.SwaggerEndpoint("/api/abc/swagger/v1/swagger.json", "API V1");
        c.RoutePrefix = "api/abc/swagger";
    });
}

Then whenever the api application is running, it will direct to https://localhost:7212/api/abc/swagger/index.html and show the APIs. Here's my test result.

How to configure Swagger in Dev/Test and Production environment

1 Answers1