Client Side Deep Links with WebpackDevMiddleware 404s - vue.js

Question

I am using the WebpackDevMiddleware for Development builds to serve up a Vue.js application that uses client-side routing. The SPA application is served up from the root url just fine, but if I attempt to use any client-side deep links, I get a 404.
Note running as Production works as expected.
What I want:
http://locahost/ - serve up the vue app.
http://localhost/overlays/chat - serve up the vue app.
http://localhost/api/* - serve up the api routes handled server side.
There is a minimum viable reproduction of the problem in this repository. You can run it using vscode debugging as Development environment where the bug happens. There is also a script /scripts/local-production that will build and run as Production environment, where it works as expected.
Relevant portions of my Startup.cs looks like this:
public class Startup
{
public IConfiguration Configuration { get; }
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
public void ConfigureServices(IServiceCollection services)
{
services.AddMvc();
// In production, the Vue files will be served
// from this directory
services.AddSpaStaticFiles(configuration =>
{
configuration.RootPath = Configuration["Client"];
});
}
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
//set up default mvc routing
app.UseMvc(routes =>
{
routes.MapRoute("default", "api/{controller=Home}/{action=Index}/{id?}");
});
//setup spa routing for both dev and prod
if (env.IsDevelopment())
{
app.UseWebpackDevMiddleware(new WebpackDevMiddlewareOptions {
HotModuleReplacement = true,
ProjectPath = Path.Combine(env.ContentRootPath, Configuration["ClientProjectPath"]),
ConfigFile = Path.Combine(env.ContentRootPath, Configuration["ClientProjectConfigPath"])
});
}
else
{
app.UseWhen(context => !context.Request.Path.Value.StartsWith("/api"),
builder => {
app.UseSpaStaticFiles();
app.UseSpa(spa => {
spa.Options.DefaultPage = "/index.html";
});
app.UseMvc(routes => {
routes.MapSpaFallbackRoute(
name: "spa-fallback",
defaults: new { controller = "Fallback", action = "Index" });
});
});
}
}
}

Answer 1

I was able to get around this using the status code pages middleware to handle all status codes and re-execute using the root path. This will cause the spa app to be served up for all status codes in the 400-599 range which is not quite what I want but gets me working again at least.
//setup spa routing for both dev and prod
if (env.IsDevelopment())
{
//force client side deep links to render the spa on 404s
app.UseStatusCodePagesWithReExecute("/");
app.UseWebpackDevMiddleware(new WebpackDevMiddlewareOptions {
HotModuleReplacement = true,
ProjectPath = Path.Combine(env.ContentRootPath, Configuration["ClientProjectPath"]),
ConfigFile = Path.Combine(env.ContentRootPath, Configuration["ClientProjectConfigPath"])
});
}
Hopefully, this will help someone in the future that might be bumping up against this issue.