Angular 8 .NET Core 3.0.CORS error in some requests but not others

Question

I'm working on a website(Angular 8 .NET Core 3.0) that takes a url and tries to fetch the og tags from the page. I referred to the first answer on stackoverflow

Startup.cs

--ConfigureServices    
services.AddCors(o => o.AddPolicy("CORSPolicy", builder =>
            {
                builder.AllowAnyOrigin()
                       .AllowAnyMethod()
                       .AllowAnyHeader();
            }));
--Configure
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }
        else
        {
            app.UseExceptionHandler("/Error");
            // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
            app.UseHsts();
        }

        app.UseHttpsRedirection();
        app.UseCors("CORSPolicy");
        app.UseStaticFiles();
        if (!env.IsDevelopment())
        {
            app.UseSpaStaticFiles();
        }

        app.UseRouting();

        app.UseEndpoints(endpoints =>
        {
            endpoints.MapControllerRoute(
                name: "default",
                pattern: "{controller}/{action=Index}/{id?}");
        });

        app.UseSpa(spa =>
        {
            spa.Options.SourcePath = "ClientApp";

            if (env.IsDevelopment())
            {
                spa.UseAngularCliServer(npmScript: "start");
            }
        });
    }

Now I do a get request using below call.

this.httpCli.get(this.URL, { headers: headers }).subscribe(result => {
        console.log(result);
    }, error => {
            console.error(error.text);
            console.error(error);
    });

I still get

blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

for some urls. Because the output is HTML, i get HttpErrorResponse but with status ok and error text having the webpage source. I need the HTML source to pull the og meta tags from .

How do I fix both these issues?

could you please update the question so that it includes cors configuration in startup.cs? — Arjun Vachhani, Nov 19 '19 at 06:12
You should share your pipeline configuration too. Order of the pipeline is crucial. So configuring CORS before the other middlewares is important. Also you can try modifying your method with EnableCorse attribute. — Eldar, Nov 19 '19 at 13:11
I've updated the Question. i did add EnableCors to my controller as well — Gowtham M, Nov 21 '19 at 04:10

score 1 · Answer 1 · answered Nov 19 '19 at 05:49

1

You are getting html as a response from the endpoint. but it should be json response. so mostly you are getting error response from server as html. first check this url is correct in postman or alike.

answered Nov 19 '19 at 05:49

prisar

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Angular 8 .NET Core 3.0.CORS error in some requests but not others

1 Answers1