[jetty-http-spi] add filter support (#12764)

* [jetty-http-spi] add filter support and test

Author: SentryMan

jetty-core/jetty-http-spi/src/main/java/org/eclipse/jetty/http/spi/HttpSpiContextHandler.java

@@ -18,6 +18,7 @@
 
 import com.sun.net.httpserver.Authenticator;
 import com.sun.net.httpserver.Authenticator.Result;
+import com.sun.net.httpserver.Filter.Chain;
 import com.sun.net.httpserver.HttpContext;
 import com.sun.net.httpserver.HttpExchange;
 import com.sun.net.httpserver.HttpHandler;
@@ -61,7 +62,7 @@ public boolean handle(Request request, Response response, Callback callback)
                     if (auth != null && handleAuthentication(request, response, callback, jettyHttpExchange, auth))
                         return true;
 
-                    _httpHandler.handle(jettyHttpExchange);
+                    new Chain(_httpContext.getFilters(), _httpHandler).doFilter(jettyHttpExchange);
                     callback.succeeded();
                 }
                 catch (Exception ex)

jetty-core/jetty-http-spi/src/test/java/org/eclipse/jetty/http/spi/SPIServerTest.java

@@ -21,8 +21,10 @@
 import java.net.URI;
 import java.nio.charset.StandardCharsets;
 import java.util.List;
+import java.util.concurrent.atomic.AtomicReference;
 
 import com.sun.net.httpserver.BasicAuthenticator;
+import com.sun.net.httpserver.Filter;
 import com.sun.net.httpserver.Headers;
 import com.sun.net.httpserver.HttpContext;
 import com.sun.net.httpserver.HttpExchange;
@@ -404,4 +406,54 @@ public boolean checkCredentials(String username, String password)
         String body = response.getContentAsString();
         assertThat(body, is("Hello"));
     }
+    
+    @Test
+    public void testFilter() throws Exception
+    {
+        final AtomicReference<String> reference = new AtomicReference<String>();
+
+        final HttpContext httpContext = server.createContext("/", new HttpHandler()
+        {
+            public void handle(HttpExchange exchange) throws IOException
+            {
+                assertThat(reference.get(), is("before"));
+                Headers responseHeaders = exchange.getResponseHeaders();
+                responseHeaders.set("Content-Type", "text/plain");
+                exchange.sendResponseHeaders(200, 0);
+
+                OutputStream responseBody = exchange.getResponseBody();
+                responseBody.write("Hello".getBytes(StandardCharsets.ISO_8859_1));
+                responseBody.close();
+            }
+        });
+
+        httpContext.getFilters().add(new Filter()
+        {
+          @Override
+          public void doFilter(HttpExchange exchange, Chain chain) throws IOException 
+          {
+            reference.set("before");
+            chain.doFilter(exchange);
+            reference.set("after");
+            
+          }
+
+          @Override
+          public String description() 
+          {
+            return "test";
+          }
+      });
+
+        Request request = client.newRequest("localhost", port)
+            .scheme("http")
+            .method(HttpMethod.GET)
+            .path("/");
+
+        ContentResponse response = request.send();
+        assertThat(response.getStatus(), is(200));
+        String body = response.getContentAsString();
+        assertThat(body, is("Hello"));
+        assertThat(reference.get(), is("after"));
+    }
 }