[UNDERTOW-1735] add reason-phrase handler and make response-code obey doc contract of one-by-one execution

Author: baranowb

core/src/main/java/io/undertow/server/handlers/ReasonPhraseHandler.java

@@ -0,0 +1,66 @@
+/*
+ * JBoss, Home of Professional Open Source.
+ * Copyright 2022 Red Hat, Inc., and individual contributors
+ * as indicated by the @author tags.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package io.undertow.server.handlers;
+
+import io.undertow.UndertowLogger;
+import io.undertow.server.HttpHandler;
+import io.undertow.server.HttpServerExchange;
+
+/**
+ * A handler which simply sets a response code.
+ *
+ * @author <a href="mailto:[email protected]">Bartosz Baranowski</a>
+ */
+public final class ReasonPhraseHandler implements HttpHandler {
+
+    private static final boolean debugEnabled;
+
+    static {
+        debugEnabled = UndertowLogger.PREDICATE_LOGGER.isDebugEnabled();
+    }
+
+    private final String reasonPhrase;
+
+    private final HttpHandler next;
+    /**
+     * Construct a new instance.
+     *
+     * @param reasonPhrase the reason phrase to be set in status line
+     */
+    public ReasonPhraseHandler(final HttpHandler next, final String reasonPhrase) {
+        this.next = next;
+        this.reasonPhrase = reasonPhrase;
+    }
+
+    @Override
+    public void handleRequest(final HttpServerExchange exchange) throws Exception {
+        exchange.setReasonPhrase(reasonPhrase);
+        if(debugEnabled) {
+            UndertowLogger.PREDICATE_LOGGER.debugf("Reason phrase set to [%s] for %s.", this.reasonPhrase, exchange);
+        }
+        if(next != null) {
+            next.handleRequest(exchange);
+        }
+    }
+
+    @Override
+    public String toString() {
+        return "reason-phrase( " + this.reasonPhrase + " )";
+    }
+}

core/src/main/java/io/undertow/server/handlers/ResponseCodeHandler.java

@@ -64,13 +64,34 @@ public final class ResponseCodeHandler implements HttpHandler {
 
     private final int responseCode;
 
+    private HttpHandler next;
     /**
      * Construct a new instance.
      *
      * @param responseCode the response code to set
+     * @param next next handler
      */
-    public ResponseCodeHandler(final int responseCode) {
+    public ResponseCodeHandler(final HttpHandler next, final int responseCode) {
         this.responseCode = responseCode;
+        this.next = next;
+    }
+
+    /**
+     * Construct a new instance.
+     *
+     * @param responseCode the response code to set
+     * @param next next handler
+     */
+    public ResponseCodeHandler(final int responseCode) {
+        this(null,responseCode);
+    }
+
+    public HttpHandler getNext() {
+        return next;
+    }
+
+    public void setNext(HttpHandler next) {
+        this.next = next;
     }
 
     @Override
@@ -79,6 +100,9 @@ public void handleRequest(final HttpServerExchange exchange) throws Exception {
         if(debugEnabled) {
             UndertowLogger.PREDICATE_LOGGER.debugf("Response code set to [%s] for %s.", responseCode, exchange);
         }
+        if(next != null) {
+            next.handleRequest(exchange);
+        }
     }
 
     @Override

core/src/main/java/io/undertow/server/handlers/builder/ReasonPhraseHandlerBuilder.java

@@ -0,0 +1,68 @@
+/*
+ * JBoss, Home of Professional Open Source.
+ * Copyright 2022 Red Hat, Inc., and individual contributors
+ * as indicated by the @author tags.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package io.undertow.server.handlers.builder;
+
+import io.undertow.server.HandlerWrapper;
+import io.undertow.server.HttpHandler;
+import io.undertow.server.handlers.ReasonPhraseHandler;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * @author Bartosz Baranowski
+ */
+public class ReasonPhraseHandlerBuilder implements HandlerBuilder {
+    @Override
+    public String name() {
+        return "reason-phrase";
+    }
+
+    @Override
+    public Map<String, Class<?>> parameters() {
+        Map<String, Class<?>> parameters = new HashMap<>();
+        parameters.put("value", String.class);
+        return parameters;
+    }
+
+    @Override
+    public Set<String> requiredParameters() {
+        final Set<String> req = new HashSet<>();
+        req.add("value");
+        return req;
+    }
+
+    @Override
+    public String defaultParameter() {
+        return "value";
+    }
+
+    @Override
+    public HandlerWrapper build(final Map<String, Object> config) {
+        final String value = (String) config.get("value");
+        return new HandlerWrapper() {
+            @Override
+            public HttpHandler wrap(HttpHandler handler) {
+                return new ReasonPhraseHandler(handler, value);
+            }
+        };
+    }
+}

core/src/main/java/io/undertow/server/handlers/builder/ResponseCodeHandlerBuilder.java

@@ -61,7 +61,7 @@ public HandlerWrapper build(final Map<String, Object> config) {
         return new HandlerWrapper() {
             @Override
             public HttpHandler wrap(HttpHandler handler) {
-                return new ResponseCodeHandler(value);
+                return new ResponseCodeHandler(handler, value);
             }
         };
     }

core/src/main/resources/META-INF/services/io.undertow.server.handlers.builder.HandlerBuilder

@@ -43,3 +43,4 @@ io.undertow.server.handlers.HttpContinueAcceptingHandler$Builder
 io.undertow.server.handlers.form.EagerFormParsingHandler$Builder
 io.undertow.server.handlers.SameSiteCookieHandler$Builder
 io.undertow.server.handlers.SetErrorHandler$Builder
+io.undertow.server.handlers.builder.ReasonPhraseHandlerBuilder

core/src/test/java/io/undertow/predicate/PredicateParsingTestCase.java

@@ -141,4 +141,5 @@ private void expect(String string, boolean result1, boolean result2) {
             throw new RuntimeException("String " + string, ex);
         }
     }
+
 }

core/src/test/java/io/undertow/server/handlers/PredicatedHandlersTestCase.java

@@ -145,4 +145,30 @@ public void handleRequest(HttpServerExchange exchange) throws Exception {
             client.getConnectionManager().shutdown();
         }
     }
+
+    @Test
+    public void testReasonPhrase() throws IOException {
+        DefaultServer.setRootHandler(
+                Handlers.predicates(
+
+                        PredicatedHandlersParser.parse(
+                                "path('/test') -> reason-phrase('test-my-patience');response-code(480)", getClass().getClassLoader()), new HttpHandler() {
+                            @Override
+                            public void handleRequest(HttpServerExchange exchange) throws Exception {
+                                exchange.getResponseSender().send(exchange.getRelativePath());
+                            }
+                        }));
+        TestHttpClient client = new TestHttpClient();
+        try {
+            HttpGet get = new HttpGet(DefaultServer.getDefaultServerURL() + "/test");
+
+            HttpResponse result = client.execute(get);
+            Assert.assertEquals("test-my-patience", result.getStatusLine().getReasonPhrase());
+            Assert.assertEquals(480, result.getStatusLine().getStatusCode());
+
+        } finally {
+            client.getConnectionManager().shutdown();
+        }
+
+    }
 }