1 /*

     2  * Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 

    26 package jdk.incubator.http.internal;

    27 

    28 import java.io.IOException;

    29 import java.lang.System.Logger.Level;

    30 import java.util.concurrent.CompletableFuture;

    31 import java.util.concurrent.Executor;

    32 import java.util.function.Function;

    33 import jdk.incubator.http.HttpResponse;

    34 import jdk.incubator.http.internal.common.MinimalFuture;

    35 import static jdk.incubator.http.HttpClient.Version.HTTP_1_1;

    36 import jdk.incubator.http.internal.common.Utils;

    37 

    38 /**

    39  * Splits request so that headers and body can be sent separately with optional

    40  * (multiple) responses in between (e.g. 100 Continue). Also request and

    41  * response always sent/received in different calls.

    42  *

    43  * Synchronous and asynchronous versions of each method are provided.

    44  *

    45  * Separate implementations of this class exist for HTTP/1.1 and HTTP/2

    46  *      Http1Exchange   (HTTP/1.1)

    47  *      Stream          (HTTP/2)

    48  *

    49  * These implementation classes are where work is allocated to threads.

    50  */

    51 abstract class ExchangeImpl<T> {

    52 

    53     static final boolean DEBUG = Utils.DEBUG; // Revisit: temporary dev flag.

    54     private static final System.Logger DEBUG_LOGGER =

    55             Utils.getDebugLogger("ExchangeImpl"::toString, DEBUG);

    56 

    57     final Exchange<T> exchange;

    58 

    59     ExchangeImpl(Exchange<T> e) {

    60         // e == null means a http/2 pushed stream

    61         this.exchange = e;

    62     }

    63 

    64     final Exchange<T> getExchange() {

    65         return exchange;

    66     }

    67 

    68 

    69     /**

    70      * Returns the {@link HttpConnection} instance to which this exchange is

    71      * assigned.

    72      */

    73     abstract HttpConnection connection();

    74 

    75     /**

    76      * Initiates a new exchange and assigns it to a connection if one exists

    77      * already. connection usually null.

    78      */

    79     static <U> CompletableFuture<? extends ExchangeImpl<U>>

    80     get(Exchange<U> exchange, HttpConnection connection)

    81     {

    82         if (exchange.version() == HTTP_1_1) {

    83             DEBUG_LOGGER.log(Level.DEBUG, "get: HTTP/1.1: new Http1Exchange");

    84             return createHttp1Exchange(exchange, connection);

    85         } else {

    86             Http2ClientImpl c2 = exchange.client().client2(); // TODO: improve

    87             HttpRequestImpl request = exchange.request();

    88             CompletableFuture<Http2Connection> c2f = c2.getConnectionFor(request);

    89             DEBUG_LOGGER.log(Level.DEBUG, "get: Trying to get HTTP/2 connection");

    90             return c2f.handle((h2c, t) -> createExchangeImpl(h2c, t, exchange, connection))

    91                     .thenCompose(Function.identity());

    92         }

    93     }

    94 

    95     private static <U> CompletableFuture<? extends ExchangeImpl<U>>

    96     createExchangeImpl(Http2Connection c,

    97                        Throwable t,

    98                        Exchange<U> exchange,

    99                        HttpConnection connection)

   100     {

   101         DEBUG_LOGGER.log(Level.DEBUG, "handling HTTP/2 connection creation result");

   102         boolean secure = exchange.request().secure();

   103         if (t != null) {

   104             DEBUG_LOGGER.log(Level.DEBUG,

   105                              "handling HTTP/2 connection creation failed: %s",

   106                              (Object)t);

   107             t = Utils.getCompletionCause(t);

   108             if (t instanceof Http2Connection.ALPNException) {

   109                 Http2Connection.ALPNException ee = (Http2Connection.ALPNException)t;

   110                 AbstractAsyncSSLConnection as = ee.getConnection();

   111                 DEBUG_LOGGER.log(Level.DEBUG, "downgrading to HTTP/1.1 with: %s", as);

   112                 CompletableFuture<? extends ExchangeImpl<U>> ex =

   113                         createHttp1Exchange(exchange, as);

   114                 return ex;

   115             } else {

   116                 DEBUG_LOGGER.log(Level.DEBUG, "HTTP/2 connection creation failed "

   117                                   + "with unexpected exception: %s", (Object)t);

   118                 return MinimalFuture.failedFuture(t);

   119             }

   120         }

   121         if (secure && c== null) {

   122             DEBUG_LOGGER.log(Level.DEBUG, "downgrading to HTTP/1.1 ");

   123             CompletableFuture<? extends ExchangeImpl<U>> ex =

   124                     createHttp1Exchange(exchange, null);

   125             return ex;

   126         }

   127         if (c == null) {

   128             // no existing connection. Send request with HTTP 1 and then

   129             // upgrade if successful

   130             DEBUG_LOGGER.log(Level.DEBUG, "new Http1Exchange, try to upgrade");

   131             return createHttp1Exchange(exchange, connection)

   132                     .thenApply((e) -> {

   133                         exchange.h2Upgrade();

   134                         return e;

   135                     });

   136         } else {

   137             DEBUG_LOGGER.log(Level.DEBUG, "creating HTTP/2 streams");

   138             Stream<U> s = c.createStream(exchange);

   139             CompletableFuture<? extends ExchangeImpl<U>> ex = MinimalFuture.completedFuture(s);

   140             return ex;

   141         }

   142     }

   143 

   144     private static <T> CompletableFuture<Http1Exchange<T>>

   145     createHttp1Exchange(Exchange<T> ex, HttpConnection as)

   146     {

   147         try {

   148             return MinimalFuture.completedFuture(new Http1Exchange<>(ex, as));

   149         } catch (Throwable e) {

   150             return MinimalFuture.failedFuture(e);

   151         }

   152     }

   153 

   154     /* The following methods have separate HTTP/1.1 and HTTP/2 implementations */

   155 

   156     abstract CompletableFuture<ExchangeImpl<T>> sendHeadersAsync();

   157 

   158     /** Sends a request body, after request headers have been sent. */

   159     abstract CompletableFuture<ExchangeImpl<T>> sendBodyAsync();

   160 

   161     abstract CompletableFuture<T> readBodyAsync(HttpResponse.BodyHandler<T> handler,

   162                                                 boolean returnConnectionToPool,

   163                                                 Executor executor);

   164 

   165     /**

   166      * Ignore/consume the body.

   167      */

   168     abstract CompletableFuture<Void> ignoreBody();

   169 

   170     /** Gets the response headers. Completes before body is read. */

   171     abstract CompletableFuture<Response> getResponseAsync(Executor executor);

   172 

   173 

   174     /** Cancels a request.  Not currently exposed through API. */

   175     abstract void cancel();

   176 

   177     /**

   178      * Cancels a request with a cause.  Not currently exposed through API.

   179      */

   180     abstract void cancel(IOException cause);

   181 

   182     /**

   183      * Called when the exchange is released, so that cleanup actions may be

   184      * performed - such as deregistering callbacks.

   185      * Typically released is called during upgrade, when an HTTP/2 stream

   186      * takes over from an Http1Exchange, or when a new exchange is created

   187      * during a multi exchange before the final response body was received.

   188      */

   189     abstract void released();

   190 

   191     /**

   192      * Called when the exchange is completed, so that cleanup actions may be

   193      * performed - such as deregistering callbacks.

   194      * Typically, completed is called at the end of the exchange, when the

   195      * final response body has been received (or an error has caused the

   196      * completion of the exchange).

   197      */

   198     abstract void completed();

   199 

   200     /**

   201      * Returns true if this exchange was canceled.

   202      * @return true if this exchange was canceled.

   203      */

   204     abstract boolean isCanceled();

   205 

   206     /**

   207      * Returns the cause for which this exchange was canceled, if available.

   208      * @return the cause for which this exchange was canceled, if available.

   209      */

   210     abstract Throwable getCancelCause();

   211 }