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Posted to commits@cxf.apache.org by bu...@apache.org on 2016/05/25 07:47:32 UTC
svn commit: r989092 - in /websites/production/cxf/content:
cache/docs.pageCache docs/asynchronous-client-http-transport.html
Author: buildbot
Date: Wed May 25 07:47:32 2016
New Revision: 989092
Log:
Production update by buildbot for cxf
Modified:
websites/production/cxf/content/cache/docs.pageCache
websites/production/cxf/content/docs/asynchronous-client-http-transport.html
Modified: websites/production/cxf/content/cache/docs.pageCache
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Modified: websites/production/cxf/content/docs/asynchronous-client-http-transport.html
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--- websites/production/cxf/content/docs/asynchronous-client-http-transport.html (original)
+++ websites/production/cxf/content/docs/asynchronous-client-http-transport.html Wed May 25 07:47:32 2016
@@ -116,7 +116,7 @@ Apache CXF -- Asynchronous Client HTTP T
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-<div id="ConfluenceContent"><h1 id="AsynchronousClientHTTPTransport-AsynchronousClientHTTPTransport">Asynchronous Client HTTP Transport</h1><p>By default, CXF uses a transport based on the in-JDK HttpURLConnection object to perform HTTP requests. The HttpURLConnection object uses a blocking model for all IO operations which requires a per-thread execution model. From a pure performance standpoint, this model generally performs very well, but it does have problems scaling when many requests need to be executed simultaneously.</p><p>Also, the JAX-WS specification allows for generation of asynchronous methods on generated proxies as well as using asynchronous methods on the Dispatch objects. These methods can take an AsyncHandler object and return a polling Future object so applications do not have to wait for the response. With the HttpURLConnection based transport, CXF was forced to consume a background thread for each outstanding request.</p><p>CXF also has an HTTP client transport
that is based on the <a shape="rect" class="external-link" href="http://hc.apache.org/httpcomponents-asyncclient-dev/index.html">Apache HTTP Components HttpAsyncClient</a> library. Its Maven artifactId is <span style="line-height: 1.4285715;">cxf-rt-transports-http-hc.</span><span style="line-height: 1.4285715;"> The HttpAsyncClient library uses a non-blocking IO model. This allows many more requests to be outstanding without consuming extra background threads. It also allows greater control over things like Keep-Alive handling which is very difficult or impossible with the HttpURLConnection based transport. However, the non-blocking model does not perform quite as well as the blocking model for pure synchronous request/response transactions.</span></p><p>By default, if the cxf-rt-transports-http-hc module is found on the classpath, CXF will use the HttpAsyncClient based implementation for any Async calls, but will continue to use the HttpURLConnection based transport for
synchronous calls. This allows a good balance of performance for the common synchronous cases with scalability for the asynchronous cases. However, using a contextual property of "use.async.http.conduit" and set to true/false, you can control whether the async or blocking version is used. If "true", the HttpAsyncClient will be used even for synchronous calls, if "false", asynchronous calls will rely on the traditional method of using HTTPURLConnection along with a work queue to mimic the asynchronocity.</p><p>Another reason to use the asynchronous transport is to use HTTP methods that HttpURLConnection does not support. For example, the github.com REST API specifies the use of PATCH for some cases, but HttpURLConnection rejects PATCH.</p><h3 id="AsynchronousClientHTTPTransport-UsingtheHTTPComponentsTransportfromJavaCode">Using the HTTP Components Transport from Java Code</h3><p>To force global use of the HTTP Components transport, you can set a bus-level property:</p><div class="cod
e panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+<div id="ConfluenceContent"><h1 id="AsynchronousClientHTTPTransport-AsynchronousClientHTTPTransport">Asynchronous Client HTTP Transport</h1><p>By default, CXF uses a transport based on the in-JDK HttpURLConnection object to perform HTTP requests. The HttpURLConnection object uses a blocking model for all IO operations which requires a per-thread execution model. From a pure performance standpoint, this model generally performs very well, but it does have problems scaling when many requests need to be executed simultaneously.</p><p>Also, the JAX-WS specification allows for generation of asynchronous methods on generated proxies as well as using asynchronous methods on the Dispatch objects. These methods can take an AsyncHandler object and return a polling Future object so applications do not have to wait for the response. With the HttpURLConnection based transport, CXF was forced to consume a background thread for each outstanding request.</p><p>CXF also has an HTTP client transport
that is based on the <a shape="rect" class="external-link" href="http://hc.apache.org/httpcomponents-asyncclient-dev/index.html">Apache HTTP Components HttpAsyncClient</a> library. Its Maven artifactId is <span style="line-height: 1.4285715;">cxf-rt-transports-http-hc.</span><span style="line-height: 1.4285715;"> The HttpAsyncClient library uses a non-blocking IO model. This allows many more requests to be outstanding without consuming extra background threads. It also allows greater control over things like Keep-Alive handling which is very difficult or impossible with the HttpURLConnection based transport. However, the non-blocking model does not perform quite as well as the blocking model for pure synchronous request/response transactions.</span></p><p>By default, if the cxf-rt-transports-http-hc module is found on the classpath, CXF will use the HttpAsyncClient based implementation for any Async calls, but will continue to use the HttpURLConnection based transport for
synchronous calls. This allows a good balance of performance for the common synchronous cases with scalability for the asynchronous cases. However, using a contextual property of "use.async.http.conduit" and set to true/false, you can control whether the async or blocking version is used. If "true", the HttpAsyncClient will be used even for synchronous calls, if "false", asynchronous calls will rely on the traditional method of using HTTPURLConnection along with a work queue to mimic the asynchronocity.  And if TLSClientParameters sets an SSLSocketFactory,  as SocketFactory class and SocketFactory#createSocket methods in particular are inherently blocking and sockets instantiated in such a way cannot be used for asynchronous, so this lead to use the HttpURLConnection based transport.</p><p>Another reason to use the asynchronous transport is to use HTTP methods that HttpURLConnection does not support. For example, the github.com REST API specifies the use of PATCH for some
cases, but HttpURLConnection rejects PATCH.</p><h3 id="AsynchronousClientHTTPTransport-UsingtheHTTPComponentsTransportfromJavaCode">Using the HTTP Components Transport from Java Code</h3><p>To force global use of the HTTP Components transport, you can set a bus-level property:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<pre class="brush: java; gutter: false; theme: Default" style="font-size:12px;"> Bus bus = BusFactory.getDefaultBus();
// insist on the async connector to use PATCH.
bus.setProperty(AsyncHTTPConduit.USE_ASYNC, Boolean.TRUE);</pre>
@@ -127,7 +127,7 @@ Apache CXF -- Asynchronous Client HTTP T
<pre class="brush: java; gutter: false; theme: Default" style="font-size:12px;">Credentials creds = new NTCredentials("username", "pswd", null, "domain");
bp.getRequestContext().put(Credentials.class.getName(), creds);
</pre>
-</div></div></li></ul><h3 id="AsynchronousClientHTTPTransport-Configuration">Configuration</h3><p>The Asynchronous HTTP Transport has several options that can set using Bus properties or via the OSGi configuration services to control various aspects of the underlying Apache HTTP Components HttpAsyncClient objects.</p><p>Settings related to the underlying TCP socket (see <a shape="rect" class="external-link" href="http://docs.oracle.com/javase/7/docs/api/java/net/Socket.html" rel="nofollow">java.net.Socket</a> for a definition of these values):</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.TCP_NODELAY (Default true)</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.SO_KEEPALIVE</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.SO_LINGER</p></td></tr><tr><td colspan="
1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.SO_TIMEOUT</p></td></tr></tbody></table></div><p>Settings related to Keep-Alive connection management:</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.CONNECTION_TTL</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Maximum time a connection which is released and not used <span>in the pool</span>. Default is 60000.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.MAX_CONNECTIONS</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><span>Maximum number of connections opened in total. Default is 5000.</span></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.MAX_PER_HOST_CONNECTIONS</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><span>Maximum number of connections op
ened per host. Default is 1000.</span></p></td></tr></tbody></table></div><p>Settings related to Apache HttpAsyncClient threads and selectors:</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.ioThreadCount</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Number of threads HttpAsyncClient uses to process IO events. Default is "-1" which means one thread per CPU core.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.interestOpQueued</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>true/false for whether the interest ops are queues or process directly.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.selectInterval</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Default 1000 ms. How often the selector thread wakes up if there are no eve
nts to process additional things like queue expirations.</p></td></tr></tbody></table></div><p>Setting to control which conduit is used</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.usePolicy</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>ALWAYS, ASYNC_ONLY, NEVER.</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Similar in meaning to the "use.async.http.conduit" context property described above. Whether to use the HttpAsyncClient: ALWAYS for both synchronous and asynchronous calls, ASYNC_ONLY (default) for asynchronous calls only, NEVER will use HTTPURLConnection for both types of calls.</p></td></tr></tbody></table></div></div>
+</div></div></li></ul><h3 id="AsynchronousClientHTTPTransport-Configuration">Configuration</h3><p>The Asynchronous HTTP Transport has several options that can set using Bus properties or via the OSGi configuration services to control various aspects of the underlying Apache HTTP Components HttpAsyncClient objects.</p><p>Settings related to the underlying TCP socket (see <a shape="rect" class="external-link" href="http://docs.oracle.com/javase/7/docs/api/java/net/Socket.html" rel="nofollow">java.net.Socket</a> for a definition of these values):</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.TCP_NODELAY (Default true)</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.SO_KEEPALIVE</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.SO_LINGER</p></td></tr><tr><td colspan="
1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.SO_TIMEOUT</p></td></tr></tbody></table></div><p>Settings related to Keep-Alive connection management:</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.CONNECTION_TTL</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Maximum time a connection to live(from creation to expiry)<span> </span>. Default is 60000.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.MAX_CONNECTIONS</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><span>Maximum number of connections opened in total. Default is 5000.</span></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.MAX_PER_HOST_CONNECTIONS</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><span>Maximum number of connections opened
per host. Default is 1000.</span></p></td></tr></tbody></table></div><p>Settings related to Apache HttpAsyncClient threads and selectors:</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.ioThreadCount</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Number of threads HttpAsyncClient uses to process IO events. Default is "-1" which means one thread per CPU core.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.interestOpQueued</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>true/false for whether the interest ops are queues or process directly.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.selectInterval</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Default 1000 ms. How often the selector thread wakes up if there are no events
to process additional things like queue expirations.</p></td></tr></tbody></table></div><p>Setting to control which conduit is used</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>org.apache.cxf.transport.http.async.usePolicy</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>ALWAYS, ASYNC_ONLY, NEVER.</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Similar in meaning to the "use.async.http.conduit" context property described above. Whether to use the HttpAsyncClient: ALWAYS for both synchronous and asynchronous calls, ASYNC_ONLY (default) for asynchronous calls only, NEVER will use HTTPURLConnection for both types of calls.</p></td></tr></tbody></table></div></div>
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