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 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
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 */

package org.apache.hc.core5.testing.nio;

import java.net.InetSocketAddress;
import java.util.concurrent.Future;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.hc.core5.function.Supplier;
import org.apache.hc.core5.http.ContentType;
import org.apache.hc.core5.http.HttpHost;
import org.apache.hc.core5.http.HttpResponse;
import org.apache.hc.core5.http.HttpStatus;
import org.apache.hc.core5.http.HttpVersion;
import org.apache.hc.core5.http.Message;
import org.apache.hc.core5.http.Method;
import org.apache.hc.core5.http.ProtocolVersion;
import org.apache.hc.core5.http.URIScheme;
import org.apache.hc.core5.http.impl.bootstrap.HttpAsyncServer;
import org.apache.hc.core5.http.nio.AsyncClientEndpoint;
import org.apache.hc.core5.http.nio.AsyncServerExchangeHandler;
import org.apache.hc.core5.http.nio.entity.StringAsyncEntityConsumer;
import org.apache.hc.core5.http.nio.entity.StringAsyncEntityProducer;
import org.apache.hc.core5.http.nio.support.BasicRequestProducer;
import org.apache.hc.core5.http.nio.support.BasicResponseConsumer;
import org.apache.hc.core5.http2.HttpVersionPolicy;
import org.apache.hc.core5.http2.impl.nio.bootstrap.H2AsyncRequester;
import org.apache.hc.core5.http2.impl.nio.bootstrap.H2RequesterBootstrap;
import org.apache.hc.core5.http2.impl.nio.bootstrap.H2ServerBootstrap;
import org.apache.hc.core5.http2.ssl.H2ClientTlsStrategy;
import org.apache.hc.core5.http2.ssl.H2ServerTlsStrategy;
import org.apache.hc.core5.io.CloseMode;
import org.apache.hc.core5.reactor.IOReactorConfig;
import org.apache.hc.core5.reactor.ListenerEndpoint;
import org.apache.hc.core5.testing.SSLTestContexts;
import org.apache.hc.core5.testing.classic.LoggingConnPoolListener;
import org.apache.hc.core5.util.ReflectionUtils;
import org.apache.hc.core5.util.Timeout;
import org.hamcrest.CoreMatchers;
import org.junit.Assert;
import org.junit.Assume;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.ExternalResource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class H2ProtocolNegotiationTest {

    private static final Timeout TIMEOUT = Timeout.ofSeconds(30);

    private final Logger log = LoggerFactory.getLogger(getClass());

    private HttpAsyncServer server;

    @Rule
    public ExternalResource serverResource = new ExternalResource() {

        @Override
        protected void before() throws Throwable {
            log.debug("Starting up test server");
            server = H2ServerBootstrap.bootstrap()
                    .setTlsStrategy(new H2ServerTlsStrategy(SSLTestContexts.createServerSSLContext()))
                    .setVersionPolicy(HttpVersionPolicy.NEGOTIATE)
                    .setIOReactorConfig(
                            IOReactorConfig.custom()
                                    .setSoTimeout(TIMEOUT)
                                    .build())
                    .setTlsStrategy(new H2ServerTlsStrategy(SSLTestContexts.createServerSSLContext()))
                    .register("*", new Supplier<AsyncServerExchangeHandler>() {

                        @Override
                        public AsyncServerExchangeHandler get() {
                            return new EchoHandler(2048);
                        }

                    })
                    .setStreamListener(LoggingH2StreamListener.INSTANCE)
                    .setStreamListener(LoggingHttp1StreamListener.INSTANCE_SERVER)
                    .setIOSessionDecorator(LoggingIOSessionDecorator.INSTANCE)
                    .setExceptionCallback(LoggingExceptionCallback.INSTANCE)
                    .setIOSessionListener(LoggingIOSessionListener.INSTANCE)
                    .create();
        }

        @Override
        protected void after() {
            log.debug("Shutting down test server");
            if (server != null) {
                server.close(CloseMode.GRACEFUL);
            }
        }

    };

    private H2AsyncRequester requester;

    @Rule
    public ExternalResource clientResource = new ExternalResource() {

        @Override
        protected void before() throws Throwable {
            log.debug("Starting up test client");
            requester = H2RequesterBootstrap.bootstrap()
                    .setTlsStrategy(new H2ClientTlsStrategy(SSLTestContexts.createClientSSLContext()))
                    .setVersionPolicy(HttpVersionPolicy.NEGOTIATE)
                    .setIOReactorConfig(IOReactorConfig.custom()
                            .setSoTimeout(TIMEOUT)
                            .build())
                    .setTlsStrategy(new H2ClientTlsStrategy(SSLTestContexts.createClientSSLContext()))
                    .setStreamListener(LoggingH2StreamListener.INSTANCE)
                    .setStreamListener(LoggingHttp1StreamListener.INSTANCE_CLIENT)
                    .setConnPoolListener(LoggingConnPoolListener.INSTANCE)
                    .setIOSessionDecorator(LoggingIOSessionDecorator.INSTANCE)
                    .setExceptionCallback(LoggingExceptionCallback.INSTANCE)
                    .setIOSessionListener(LoggingIOSessionListener.INSTANCE)
                    .create();
        }

        @Override
        protected void after() {
            log.debug("Shutting down test client");
            if (requester != null) {
                requester.close(CloseMode.GRACEFUL);
            }
        }

    };

    private static int javaVersion;

    @BeforeClass
    public static void determineJavaVersion() {
        javaVersion = ReflectionUtils.determineJRELevel();
    }

    @Before
    public void checkVersion() {
        Assume.assumeTrue("Java version must be 1.8 or greater", javaVersion > 7);
    }

    @Test
    public void testForceHttp1() throws Exception {
        server.start();
        final Future<ListenerEndpoint> future = server.listen(new InetSocketAddress(0), URIScheme.HTTPS);
        final ListenerEndpoint listener = future.get();
        final InetSocketAddress address = (InetSocketAddress) listener.getAddress();
        requester.start();

        final HttpHost target = new HttpHost(URIScheme.HTTPS.id, "localhost", address.getPort());
        final Future<AsyncClientEndpoint> connectFuture = requester.connect(target, TIMEOUT, HttpVersionPolicy.FORCE_HTTP_1, null);
        final AsyncClientEndpoint endpoint = connectFuture.get(TIMEOUT.getDuration(), TIMEOUT.getTimeUnit());

        final Future<Message<HttpResponse, String>> resultFuture1 = endpoint.execute(
                new BasicRequestProducer(Method.POST, target, "/stuff",
                        new StringAsyncEntityProducer("some stuff", ContentType.TEXT_PLAIN)),
                new BasicResponseConsumer<>(new StringAsyncEntityConsumer()), null);
        final Message<HttpResponse, String> message1 = resultFuture1.get(TIMEOUT.getDuration(), TIMEOUT.getTimeUnit());
        Assert.assertThat(message1, CoreMatchers.notNullValue());
        final HttpResponse response1 = message1.getHead();
        Assert.assertThat(response1.getCode(), CoreMatchers.equalTo(HttpStatus.SC_OK));
        Assert.assertThat(response1.getVersion(), CoreMatchers.<ProtocolVersion>equalTo(HttpVersion.HTTP_1_1));
    }

    @Test
    public void testForceHttp2() throws Exception {
        server.start();
        final Future<ListenerEndpoint> future = server.listen(new InetSocketAddress(0), URIScheme.HTTPS);
        final ListenerEndpoint listener = future.get();
        final InetSocketAddress address = (InetSocketAddress) listener.getAddress();
        requester.start();

        final HttpHost target = new HttpHost(URIScheme.HTTPS.id, "localhost", address.getPort());
        final Future<AsyncClientEndpoint> connectFuture = requester.connect(target, TIMEOUT, HttpVersionPolicy.FORCE_HTTP_2, null);
        final AsyncClientEndpoint endpoint = connectFuture.get(TIMEOUT.getDuration(), TIMEOUT.getTimeUnit());

        final Future<Message<HttpResponse, String>> resultFuture1 = endpoint.execute(
                new BasicRequestProducer(Method.POST, target, "/stuff",
                        new StringAsyncEntityProducer("some stuff", ContentType.TEXT_PLAIN)),
                new BasicResponseConsumer<>(new StringAsyncEntityConsumer()), null);
        final Message<HttpResponse, String> message1 = resultFuture1.get(TIMEOUT.getDuration(), TIMEOUT.getTimeUnit());
        Assert.assertThat(message1, CoreMatchers.notNullValue());
        final HttpResponse response1 = message1.getHead();
        Assert.assertThat(response1.getCode(), CoreMatchers.equalTo(HttpStatus.SC_OK));
        Assert.assertThat(response1.getVersion(), CoreMatchers.<ProtocolVersion>equalTo(HttpVersion.HTTP_2));
    }

    @Test
    public void testNegotiateProtocol() throws Exception {
        server.start();
        final Future<ListenerEndpoint> future = server.listen(new InetSocketAddress(0), URIScheme.HTTPS);
        final ListenerEndpoint listener = future.get();
        final InetSocketAddress address = (InetSocketAddress) listener.getAddress();
        requester.start();

        final HttpHost target = new HttpHost(URIScheme.HTTPS.id, "localhost", address.getPort());
        final Future<AsyncClientEndpoint> connectFuture = requester.connect(target, TIMEOUT, HttpVersionPolicy.NEGOTIATE, null);
        final AsyncClientEndpoint endpoint = connectFuture.get(TIMEOUT.getDuration(), TIMEOUT.getTimeUnit());

        final Future<Message<HttpResponse, String>> resultFuture1 = endpoint.execute(
                new BasicRequestProducer(Method.POST, target, "/stuff",
                        new StringAsyncEntityProducer("some stuff", ContentType.TEXT_PLAIN)),
                new BasicResponseConsumer<>(new StringAsyncEntityConsumer()), null);
        final Message<HttpResponse, String> message1 = resultFuture1.get(TIMEOUT.getDuration(), TIMEOUT.getTimeUnit());
        Assert.assertThat(message1, CoreMatchers.notNullValue());
        final HttpResponse response1 = message1.getHead();
        Assert.assertThat(response1.getCode(), CoreMatchers.equalTo(HttpStatus.SC_OK));

        if (isAlpnSupported()) {
            Assert.assertThat(response1.getVersion(), CoreMatchers.<ProtocolVersion>equalTo(HttpVersion.HTTP_2));
        } else {
            Assert.assertThat(response1.getVersion(), CoreMatchers.<ProtocolVersion>equalTo(HttpVersion.HTTP_1_1));
        }
    }

    private boolean isAlpnSupported() {
        if (javaVersion == 8) {
            // The 'java.version' property values are structured "1.8.0_[BUILD NUMBER]" in java 8 releases.
            final Matcher matcher = Pattern.compile("^1\\.8\\.0_(\\d+)$")
                    .matcher(System.getProperty("java.version"));
            if (matcher.matches()) {
                final int java8Build = Integer.parseInt(matcher.group(1));
                // jep244 (alpn) was backported to java 8u251.
                // https://bugs.java.com/bugdatabase/view_bug.do?bug_id=8230977
                return java8Build >= 251;
            }
        }
        return javaVersion > 8;
    }

}