我有一个ASP .NET Core自托管项目。我正在从静态文件夹中提供内容(没问题)。它可以跨站点提供图像而不会出现问题(CORS标题显示)。但是,对于某些文件类型(例如JSON),它们的CORS标头不会显示,并且客户端站点无法查看内容。如果我将文件重命名为未知类型(例如JSONX),它将使用CORS标头提供服务,没问题。如何使用CORS标头来提供这些东西呢?
我在Startup.cs中设置了以下CORS策略:
public void ConfigureServices(IServiceCollection services)
{
services.AddCors(options =>
{
options.AddPolicy("CorsPolicy",
builder => builder.AllowAnyOrigin()
.AllowAnyMethod()
.AllowAnyHeader()
.AllowCredentials() );
});
// Add framework services.
services.AddMvc();
}
以下是我的配置
public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
app.UseCors("CorsPolicy");
loggerFactory.AddConsole(Configuration.GetSection("Logging"));
loggerFactory.AddDebug();
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
app.UseBrowserLink();
}
else
{
app.UseExceptionHandler("/Home/Error");
}
// Static File options, normally would be in-line, but the SFO's file provider is not available at instantiation time
var sfo = new StaticFileOptions() { ServeUnknownFileTypes = true, DefaultContentType = "application/octet-stream", RequestPath = "/assets"};
sfo.FileProvider = new PhysicalFileProvider(Program.minervaConfig["ContentPath"]);
app.UseStaticFiles(sfo);
app.UseMvc(routes =>
{
routes.MapRoute(
name: "default",
template: "{controller=Home}/{action=Index}/{id?}");
});
}
答案 0 :(得分:0)
中间件可以帮助解决这种复杂的逻辑问题。我最近为JavaScript源代码工作了。看起来JSON的媒体类型是“application / json”。
/*
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
Made available under the Apache 2.0 license.
https://www.apache.org/licenses/LICENSE-2.0
*/
/// <summary>
/// Sets response headers for static files having certain media types.
/// In Startup.Configure, enable before UseStaticFiles with
/// app.UseMiddleware<CorsResponseHeaderMiddleware>();
/// </summary>
public class CorsResponseHeaderMiddleware
{
private readonly RequestDelegate _next;
// Must NOT have trailing slash
private readonly string AllowedOrigin = "http://server:port";
private bool IsCorsOkContentType(string fieldValue)
{
var fieldValueLower = fieldValue.ToLower();
// Add other media types here.
return (fieldValueLower.StartsWith("application/javascript"));
}
public CorsResponseHeaderMiddleware(RequestDelegate next) {
_next = next;
}
public async Task Invoke(HttpContext context)
{
context.Response.OnStarting(ignored =>
{
if (context.Response.StatusCode < 400 &&
IsCorsOkContentType(context.Response.ContentType))
{
context.Response.Headers.Add("Access-Control-Allow-Origin", AllowedOrigin);
}
return Task.FromResult(0);
}, null);
await _next(context);
}
}