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Posted to commits@camel.apache.org by bu...@apache.org on 2015/07/20 22:19:48 UTC
svn commit: r959055 [3/3] - in /websites/production/camel/content:
book-in-one-page.html book-pattern-appendix.html cache/main.pageCache
camel-2160-release.html message-endpoint.html wire-tap.html
Modified: websites/production/camel/content/wire-tap.html
==============================================================================
--- websites/production/camel/content/wire-tap.html (original)
+++ websites/production/camel/content/wire-tap.html Mon Jul 20 20:19:47 2015
@@ -86,14 +86,14 @@
<tbody>
<tr>
<td valign="top" width="100%">
-<div class="wiki-content maincontent"><h3 id="WireTap-WireTap">Wire Tap</h3><p><a shape="rect" class="external-link" href="http://www.enterpriseintegrationpatterns.com/WireTap.html" rel="nofollow">Wire Tap</a> (from the <a shape="rect" href="enterprise-integration-patterns.html">EIP patterns</a>) allows you to route messages to a separate location while they are being forwarded to the ultimate destination.</p><p><span class="confluence-embedded-file-wrapper"><img class="confluence-embedded-image confluence-external-resource" src="http://www.enterpriseintegrationpatterns.com/img/WireTap.gif" data-image-src="http://www.enterpriseintegrationpatterns.com/img/WireTap.gif"></span></p><div class="confluence-information-macro confluence-information-macro-information"><p class="title">Streams</p><span class="aui-icon aui-icon-small aui-iconfont-info confluence-information-macro-icon"></span><div class="confluence-information-macro-body"><p>If you <a shape="rect" href="wire-tap.html">Wire Tap
</a> a stream message body then you should consider enabling <a shape="rect" href="stream-caching.html">Stream caching</a> to ensure the message body can be read at each endpoint. See more details at <a shape="rect" href="stream-caching.html">Stream caching</a>.</p></div></div><h3 id="WireTap-Options">Options</h3><div class="table-wrap"><table class="confluenceTable"><tbody><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Name</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Default Value</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Description</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><code>uri</code></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>The URI of the endpoint to which the wire-tapped message will be sent. You should use either <code>uri</code> or <code>ref</code>.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>
<code>ref</code></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Reference identifier of the endpoint to which the wire-tapped message will be sent. You should use either <code>uri</code> or <code>ref</code>.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><code>executorServiceRef</code></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Reference identifier of a custom <a shape="rect" href="threading-model.html">Thread Pool</a> to use when processing the wire-tapped messages. If not set, Camel will use a default thread pool.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><code>processorRef</code></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Reference identifier of a custom <a shape="rect" href="processor.ht
ml">Processor</a> to use for creating a new message (e.g., the "send a new message" mode). See below.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><code>copy</code></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code>true</code></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>Camel 2.3</strong>: Whether to copy the <a shape="rect" href="exchange.html">Exchange</a> before wire-tapping the message.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><code>onPrepareRef</code></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>Camel 2.8:</strong> Reference identifier of a custom <a shape="rect" href="processor.html">Processor</a> to prepare the copy of the <a shape="rect" href="exchange.html">Exchange</a> to be wire-tapped. This allows you to do any custom logic, such as deep-cloning the message payload.</p></td></tr></tbody></tab
le></div><h3 id="WireTap-WireTapthreadpool">WireTap thread pool</h3><p>The <a shape="rect" href="wire-tap.html">Wire Tap</a> uses a thread pool to process the tapped messages. This thread pool will by default use the settings detailed at <a shape="rect" href="threading-model.html">Threading Model</a>. In particular, when the pool is exhausted (with all threads utilized), further wiretaps will be executed synchronously by the calling thread. To remedy this, you can configure an explicit thread pool on the <a shape="rect" href="wire-tap.html">Wire Tap</a> having either a different rejection policy, a larger worker queue, or more worker threads.</p><h3 id="WireTap-WireTapnode">WireTap node</h3><p>Camel's Wire Tap node supports two flavors when tapping an <a shape="rect" href="exchange.html">Exchange</a>:</p><p>-With the traditional Wire Tap, Camel will copy the original <a shape="rect" href="exchange.html">Exchange</a> and set its <a shape="rect" href="exchange-pattern.html">Exchange P
attern</a> to InOnly, as we want the tapped <a shape="rect" href="exchange.html">Exchange</a> to be sent in a fire and forget style. The tapped <a shape="rect" href="exchange.html">Exchange</a> is then sent in a separate thread so it can run in parallel with the original. Beware that only the Exchange is copied - Wire Tap won't do a deep clone (unless you specify a custom processor via <em>onPrepareRef</em> which does that). So all copies could share objects from the original Exchange.</p><p>-Camel also provides an option of sending a new <a shape="rect" href="exchange.html">Exchange</a> allowing you to populate it with new values.</p><h4 id="WireTap-Sendingacopy(traditionalwiretap)">Sending a copy (traditional wiretap)</h4><p><strong>Using the <a shape="rect" href="fluent-builders.html">Fluent Builders</a></strong></p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+<div class="wiki-content maincontent"><h3 id="WireTap-WireTap">Wire Tap</h3><p><a shape="rect" class="external-link" href="http://www.enterpriseintegrationpatterns.com/WireTap.html" rel="nofollow">Wire Tap</a> (from the <a shape="rect" href="enterprise-integration-patterns.html">EIP patterns</a>) allows you to route messages to a separate location while they are being forwarded to the ultimate destination.</p><p><span class="confluence-embedded-file-wrapper"><img class="confluence-embedded-image confluence-external-resource" src="http://www.enterpriseintegrationpatterns.com/img/WireTap.gif" data-image-src="http://www.enterpriseintegrationpatterns.com/img/WireTap.gif"></span></p><div class="confluence-information-macro confluence-information-macro-information"><p class="title">Streams</p><span class="aui-icon aui-icon-small aui-iconfont-info confluence-information-macro-icon"></span><div class="confluence-information-macro-body"><p>If you <a shape="rect" href="wire-tap.html">Wire Tap
</a> a stream message body then you should consider enabling <a shape="rect" href="stream-caching.html">Stream caching</a> to ensure the message body can be read at each endpoint. See more details at <a shape="rect" href="stream-caching.html">Stream caching</a>.</p></div></div><h3 id="WireTap-Options">Options</h3><div class="table-wrap"><table class="confluenceTable"><tbody><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Name</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Default Value</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Description</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><code>uri</code></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>Mandatory:</strong> The URI of the endpoint to which the wire-tapped message will be sent. From <strong>Camel 2.16</strong> onwards support dynamic to uris like documented in <a shape="rect" c
lass="external-link" href="http://camel.apache.org/message-endpoint.html" style="line-height: 1.4285715;">Message Endpoint</a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><code>executorServiceRef</code></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Reference identifier of a custom <a shape="rect" href="threading-model.html">Thread Pool</a> to use when processing the wire-tapped messages. If not set, Camel will use a default thread pool.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><code>processorRef</code></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Reference identifier of a custom <a shape="rect" href="processor.html">Processor</a> to use for creating a new message (e.g., the "send a new message" mode). See below.</p></td></tr><tr><td colspan="1" rowspan="1" class="conflue
nceTd"><p><code>copy</code></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code>true</code></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>Camel 2.3</strong>: Whether to copy the <a shape="rect" href="exchange.html">Exchange</a> before wire-tapping the message.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><code>onPrepareRef</code></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>Camel 2.8:</strong> Reference identifier of a custom <a shape="rect" href="processor.html">Processor</a> to prepare the copy of the <a shape="rect" href="exchange.html">Exchange</a> to be wire-tapped. This allows you to do any custom logic, such as deep-cloning the message payload.</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><code>cacheSize</code></td><td colspan="1" rowspan="1" class="confluenceTd"> </td><td colspan="1" rowspan="1" class=
"confluenceTd"><span style="color: rgb(0,0,0);"><strong>Camel 2.16:</strong> Allows to configure the cache size for the </span><code>ProducerCache</code><span style="color: rgb(0,0,0);"> which caches producers for reuse. Will by default use the default cache size which is 1000. Setting the value to -1 allows to turn off the cache all together.</span></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><code>ignoreInvalidEndpoint</code></td><td colspan="1" rowspan="1" class="confluenceTd"><code>false</code></td><td colspan="1" rowspan="1" class="confluenceTd"><strong>Camel 2.16:</strong> <span style="color: rgb(0,0,0);">Whether to ignore an endpoint URI that could not be resolved. If disabled, Camel will throw an exception identifying the invalid endpoint URI.</span></td></tr></tbody></table></div><h3 id="WireTap-WireTapthreadpool">WireTap thread pool</h3><p>The <a shape="rect" href="wire-tap.html">Wire Tap</a> uses a thread pool to process the tapped messages. Th
is thread pool will by default use the settings detailed at <a shape="rect" href="threading-model.html">Threading Model</a>. In particular, when the pool is exhausted (with all threads utilized), further wiretaps will be executed synchronously by the calling thread. To remedy this, you can configure an explicit thread pool on the <a shape="rect" href="wire-tap.html">Wire Tap</a> having either a different rejection policy, a larger worker queue, or more worker threads.</p><h3 id="WireTap-WireTapnode">WireTap node</h3><p>Camel's Wire Tap node supports two flavors when tapping an <a shape="rect" href="exchange.html">Exchange</a>:</p><p>-With the traditional Wire Tap, Camel will copy the original <a shape="rect" href="exchange.html">Exchange</a> and set its <a shape="rect" href="exchange-pattern.html">Exchange Pattern</a> to InOnly, as we want the tapped <a shape="rect" href="exchange.html">Exchange</a> to be sent in a fire and forget style. The tapped <a shape="rect" href="exchange.htm
l">Exchange</a> is then sent in a separate thread so it can run in parallel with the original. Beware that only the Exchange is copied - Wire Tap won't do a deep clone (unless you specify a custom processor via <em>onPrepareRef</em> which does that). So all copies could share objects from the original Exchange.</p><p>-Camel also provides an option of sending a new <a shape="rect" href="exchange.html">Exchange</a> allowing you to populate it with new values.</p><h4 id="WireTap-Sendingacopy(traditionalwiretap)">Sending a copy (traditional wiretap)</h4><p><strong>Using the <a shape="rect" href="fluent-builders.html">Fluent Builders</a></strong></p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="brush: java; gutter: false; theme: Default" type="syntaxhighlighter"><![CDATA[
from("direct:start")
.to("log:foo")
.wireTap("direct:tap")
.to("mock:result");
]]></script>
-</div></div><p><strong>Using the <a shape="rect" href="spring-xml-extensions.html">Spring XML Extensions</a></strong></p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div><strong>Using the <a shape="rect" href="spring-xml-extensions.html">Spring XML Extensions</a></strong><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="brush: xml; gutter: false; theme: Default" type="syntaxhighlighter"><![CDATA[
<route>
<from uri="direct:start"/>
@@ -115,7 +115,7 @@ from("direct:start")
from("direct:foo").to("mock:foo");
]]></script>
-</div></div><p>Here is the <a shape="rect" href="expression.html">Expression</a> variation. This example is from Camel 2.3, where we disable <code>copy</code> by passing in <code>false</code> to create a new, empty <a shape="rect" href="exchange.html">Exchange</a>.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div>Here is the <a shape="rect" href="expression.html">Expression</a> variation. This example is from Camel 2.3, where we disable <code>copy</code> by passing in <code>false</code> to create a new, empty <a shape="rect" href="exchange.html">Exchange</a>.<div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="brush: java; gutter: false; theme: Default" type="syntaxhighlighter"><![CDATA[
from("direct:start")
.wireTap("direct:foo", false, constant("Bye World"))
@@ -123,7 +123,7 @@ from("direct:start")
from("direct:foo").to("mock:foo");
]]></script>
-</div></div><p><strong>Using the <a shape="rect" href="spring-xml-extensions.html">Spring XML Extensions</a></strong><br clear="none"> The processor variation, which uses a <strong>processorRef</strong> attribute to refer to a Spring bean by ID:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div><strong>Using the <a shape="rect" href="spring-xml-extensions.html">Spring XML Extensions</a></strong><br clear="none"> The processor variation, which uses a <strong>processorRef</strong> attribute to refer to a Spring bean by ID:<div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="brush: xml; gutter: false; theme: Default" type="syntaxhighlighter"><![CDATA[
<route>
<from uri="direct:start2"/>
@@ -131,7 +131,7 @@ from("direct:foo").to("mo
<to uri="mock:result"/>
</route>
]]></script>
-</div></div><p>Here is the <a shape="rect" href="expression.html">Expression</a> variation, where the expression is defined in the <strong>body</strong> tag:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div>Here is the <a shape="rect" href="expression.html">Expression</a> variation, where the expression is defined in the <strong>body</strong> tag:<div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="brush: xml; gutter: false; theme: Default" type="syntaxhighlighter"><![CDATA[
<route>
<from uri="direct:start"/>
@@ -141,7 +141,7 @@ from("direct:foo").to("mo
<to uri="mock:result"/>
</route>
]]></script>
-</div></div><p>This variation accesses the body of the original message and creates a new <a shape="rect" href="exchange.html">Exchange</a> based on the <a shape="rect" href="expression.html">Expression</a>. It will create a new Exchange and have the body contain <code>"Bye ORIGINAL BODY MESSAGE HERE"</code></p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div>This variation accesses the body of the original message and creates a new <a shape="rect" href="exchange.html">Exchange</a> based on the <a shape="rect" href="expression.html">Expression</a>. It will create a new Exchange and have the body contain <code>"Bye ORIGINAL BODY MESSAGE HERE"</code><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="brush: xml; gutter: false; theme: Default" type="syntaxhighlighter"><![CDATA[
<route>
<from uri="direct:start"/>
@@ -151,7 +151,11 @@ from("direct:foo").to("mo
<to uri="mock:result"/>
</route>
]]></script>
-</div></div><h4 id="WireTap-FurtherExample">Further Example</h4><p>For another example of this pattern, refer to the <a shape="rect" class="external-link" href="http://svn.apache.org/repos/asf/camel/trunk/camel-core/src/test/java/org/apache/camel/processor/WireTapTest.java">wire tap test case</a>.</p><h3 id="WireTap-SendinganewandsetheadersinDSL">Sending a new <a shape="rect" href="exchange.html">Exchange</a> and set headers in DSL</h3><p><strong>Available as of Camel 2.8</strong></p><p>If you send a new message using <a shape="rect" href="wire-tap.html">Wire Tap</a>, then you could only set the message body using an <a shape="rect" href="expression.html">Expression</a> from the DSL. If you also need to set headers, you would have to use a <a shape="rect" href="processor.html">Processor</a>. In Camel 2.8 onwards, you can now set headers as well in the DSL.</p><p>The following example sends a new message which has</p><ul class="alternate"><li>"Bye World" as message body</li><li>a hea
der with key "id" with the value 123</li><li>a header with key "date" which has current date as value</li></ul><h4 id="WireTap-JavaDSL">Java DSL</h4><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div><h4 id="WireTap-FurtherExample">Further Example</h4><p>For another example of this pattern, refer to the <a shape="rect" class="external-link" href="http://svn.apache.org/repos/asf/camel/trunk/camel-core/src/test/java/org/apache/camel/processor/WireTapTest.java">wire tap test case</a>.</p><h3 id="WireTap-UsingDynamicUris">Using Dynamic Uris</h3><p><strong>Available as of Camel 2.16:</strong></p><p>For example to wire tap to a dynamic uri, then it supports the same dynamic uris as documented in <a shape="rect" href="message-endpoint.html">Message Endpoint</a>. For example to wire tap to a JMS queue where the header ID is part of the queue name</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+<script class="brush: java; gutter: false; theme: Default" type="syntaxhighlighter"><![CDATA[from("direct:start")
+ .wireTap("jms:queue:backup-${header.id}")
+ .to("bean:doSomething");]]></script>
+</div></div><p> </p><h3 id="WireTap-SendinganewandsetheadersinDSL">Sending a new <a shape="rect" href="exchange.html">Exchange</a> and set headers in DSL</h3><p><strong>Available as of Camel 2.8</strong></p><p>If you send a new message using <a shape="rect" href="wire-tap.html">Wire Tap</a>, then you could only set the message body using an <a shape="rect" href="expression.html">Expression</a> from the DSL. If you also need to set headers, you would have to use a <a shape="rect" href="processor.html">Processor</a>. In Camel 2.8 onwards, you can now set headers as well in the DSL.</p><p>The following example sends a new message which has</p><ul class="alternate"><li>"Bye World" as message body</li><li>a header with key "id" with the value 123</li><li>a header with key "date" which has current date as value</li></ul><h4 id="WireTap-JavaDSL">Java DSL</h4><p></p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="brush: java; gutter: false; theme: Default" type="syntaxhighlighter"><![CDATA[
from("direct:start")
// tap a new message and send it to direct:tap