/// <summary>
/// Configures the application to forward incoming requests to a local Single Page
/// Application (SPA) development server. This is only intended to be used during
/// development. Do not enable this middleware in production applications.
/// </summary>
/// <param name="spaBuilder">The <see cref="IMulitSpaBuilder"/>.</param>
/// <param name="baseUriTaskFactory">A callback that will be invoked on each request to supply a <see cref="Task"/> that resolves with the target base URI to which requests should be proxied.</param>
public static void UseProxyToSpaDevelopmentServer(
this IMulitSpaBuilder spaBuilder,
Func <Task <Uri> > baseUriTaskFactory)
{
var applicationBuilder = spaBuilder.ApplicationBuilder;
var applicationStoppingToken = GetStoppingToken(applicationBuilder);
// Since we might want to proxy WebSockets requests (e.g., by default, AngularCliMiddleware
// requires it), enable it for the app
applicationBuilder.UseWebSockets();
// It's important not to time out the requests, as some of them might be to
// server-sent event endpoints or similar, where it's expected that the response
// takes an unlimited time and never actually completes
var neverTimeOutHttpClient =
SpaProxy.CreateHttpClientForProxy(Timeout.InfiniteTimeSpan);
// Proxy all requests to the SPA development server
applicationBuilder.Use(async(context, next) =>
{
if (context.Request.Path.StartsWithSegments(PathString.FromUriComponent(spaBuilder.Options.PublicPath)))
{
var didProxyRequest = await SpaProxy.PerformProxyRequest(
context, neverTimeOutHttpClient, baseUriTaskFactory(), applicationStoppingToken,
proxy404s: true);
}
else
{
await next();
}
});
}
public async Task Invoke(HttpContext context)
{
if (context.Request.Path.StartsWithSegments(_pathPrefix) || _pathPrefixIsRoot)
{
var didProxyRequest = await SpaProxy.PerformProxyRequest(
context, _httpClient, _baseUriTask, _applicationStoppingToken, proxy404s : false);
if (didProxyRequest)
{
return;
}
}
// Not a request we can proxy
await _next.Invoke(context);
}
public ConditionalProxyMiddleware(
RequestDelegate next,
string pathPrefix,
TimeSpan requestTimeout,
Task <Uri> baseUriTask,
IHostApplicationLifetime applicationLifetime)
{
if (!pathPrefix.StartsWith("/"))
{
pathPrefix = "/" + pathPrefix;
}
_next = next;
_pathPrefix = pathPrefix;
_pathPrefixIsRoot = string.Equals(_pathPrefix, "/", StringComparison.Ordinal);
_baseUriTask = baseUriTask;
_httpClient = SpaProxy.CreateHttpClientForProxy(requestTimeout);
_applicationStoppingToken = applicationLifetime.ApplicationStopping;
}
