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Posted to commits@sling.apache.org by bu...@apache.org on 2016/01/07 10:26:52 UTC
svn commit: r977219 - in /websites/staging/sling/trunk/content: ./
documentation/bundles/metric-web-console.png
documentation/bundles/metrics.html
Author: buildbot
Date: Thu Jan 7 09:26:52 2016
New Revision: 977219
Log:
Staging update by buildbot for sling
Added:
websites/staging/sling/trunk/content/documentation/bundles/metric-web-console.png (with props)
websites/staging/sling/trunk/content/documentation/bundles/metrics.html
Modified:
websites/staging/sling/trunk/content/ (props changed)
Propchange: websites/staging/sling/trunk/content/
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+1723490
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--- websites/staging/sling/trunk/content/documentation/bundles/metrics.html (added)
+++ websites/staging/sling/trunk/content/documentation/bundles/metrics.html Thu Jan 7 09:26:52 2016
@@ -0,0 +1,226 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
+<html>
+<!--
+
+ Licensed to the Apache Software Foundation (ASF) under one or more
+ contributor license agreements. See the NOTICE file 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.
+-->
+ <head>
+ <meta http-equiv="Content-Type" content="text/html;charset=UTF-8">
+ <title>Apache Sling - Sling Metrics</title>
+ <link rel="icon" href="/res/favicon.ico">
+ <link rel="stylesheet" href="/res/site.css" type="text/css" media="all">
+ <link rel="stylesheet" href="/res/codehilite.css" type="text/css" media="all">
+ </head>
+ <body>
+ <div class="title">
+ <div class="logo">
+ <a href="//sling.apache.org/">
+ <img border="0" alt="Apache Sling" src="/res/logo.png">
+ </a>
+ </div>
+ <div class="header">
+ <a href="//www.apache.org/">
+ <img border="0" alt="Apache" src="/res/apache.png">
+ </a>
+ </div>
+ </div>
+
+ <div class="menu">
+ <style type="text/css">
+/* The following code is added by mdx_elementid.py
+ It was originally lifted from http://subversion.apache.org/style/site.css */
+/*
+ * Hide class="elementid-permalink", except when an enclosing heading
+ * has the :hover property.
+ */
+.headerlink, .elementid-permalink {
+ visibility: hidden;
+}
+h2:hover > .headerlink, h3:hover > .headerlink, h1:hover > .headerlink, h6:hover > .headerlink, h4:hover > .headerlink, h5:hover > .headerlink, dt:hover > .elementid-permalink { visibility: visible }</style>
+<p><strong><a href="/documentation.html">Documentation</a></strong> <br />
+<a href="/documentation/getting-started.html">Getting Started</a> <br />
+<a href="/documentation/the-sling-engine.html">The Sling Engine</a> <br />
+<a href="/documentation/development.html">Development</a> <br />
+<a href="/documentation/bundles.html">Bundles</a> <br />
+<a href="/documentation/tutorials-how-tos.html">Tutorials & How-Tos</a> <br />
+<a href="/documentation/configuration.html">Configuration</a> </p>
+<p><a href="http://s.apache.org/sling.wiki">Wiki</a> <br />
+<a href="http://s.apache.org/sling.faq">FAQ</a> </p>
+<p><strong>API Docs</strong> <br />
+<a href="/apidocs/sling8/index.html">Sling 8</a> <br />
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+<a href="/apidocs/sling5/index.html">Sling 5</a> <br />
+<a href="/javadoc-io.html">Archive at javadoc.io</a> </p>
+<p><strong>Project info</strong> <br />
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+<a href="/news.html">News</a> <br />
+<a href="/links.html">Links</a> <br />
+<a href="/project-information.html">Project Information</a> <br />
+<a href="https://issues.apache.org/jira/browse/SLING">Issue Tracker</a> <br />
+<a href="http://ci.apache.org/builders/sling-trunk">Build Server</a> <br />
+<a href="/project-information/security.html">Security</a> </p>
+<p><strong>Source</strong> <br />
+<a href="http://svn.apache.org/viewvc/sling/trunk">Subversion</a> <br />
+<a href="git://git.apache.org/sling.git">Git</a> <br />
+<a href="https://github.com/apache/sling">Github Mirror</a> </p>
+<p><strong>Sponsorship</strong> <br />
+<a href="http://www.apache.org/foundation/thanks.html">Thanks</a> <br />
+<a href="http://www.apache.org/foundation/sponsorship.html">Become a Sponsor</a> <br />
+<a href="http://www.apache.org/foundation/buy_stuff.html">Buy Stuff</a> </p>
+<p><strong><a href="/sitemap.html">Site Map</a></strong></p>
+<!-- no valid ads for now, we'll reactivate this when needed
+<iframe
+ src="http://www.apache.org/ads/button.html"
+ style="border-width:0; float: left" frameborder="0"
+ scrolling="no"
+ width="135"
+ height="135">
+</iframe>
+-->
+ </div>
+
+ <div class="main">
+ <div class="breadcrump" style="font-size: 80%;">
+ <a href="/">Home</a> » <a href="/documentation.html">Documentation</a> » <a href="/documentation/bundles.html">Bundles</a>
+ </div>
+
+
+
+ <h1>Sling Metrics</h1>
+ <style type="text/css">
+/* The following code is added by mdx_elementid.py
+ It was originally lifted from http://subversion.apache.org/style/site.css */
+/*
+ * Hide class="elementid-permalink", except when an enclosing heading
+ * has the :hover property.
+ */
+.headerlink, .elementid-permalink {
+ visibility: hidden;
+}
+h2:hover > .headerlink, h3:hover > .headerlink, h1:hover > .headerlink, h6:hover > .headerlink, h4:hover > .headerlink, h5:hover > .headerlink, dt:hover > .elementid-permalink { visibility: visible }</style>
+<p>Sling Metrics bundle provides integration with <a href="http://metrics.dropwizard.io/">Dropwizard Metrics</a> library
+which provides a toolkit to capture runtime performance statistics in your
+application. </p>
+<h2 id="features">Features<a class="headerlink" href="#features" title="Permanent link">¶</a></h2>
+<ul>
+<li>Registers a <a href="https://github.com/apache/sling/blob/trunk/bundles/commons/metrics/src/main/java/org/apache/sling/commons/metrics/MetricsService.java">MetricsService</a> which can be used to create various types of Metric
+ instances</li>
+<li>WebConsole Plugin which provides a HTML Reporter for the various Metric instances</li>
+<li>Inventory Plugin which dumps the Metric state in plain text format</li>
+</ul>
+<h2 id="basic-usage">Basic Usage<a class="headerlink" href="#basic-usage" title="Permanent link">¶</a></h2>
+<div class="codehilite"><pre><span class="kn">import</span> <span class="nn">org.apache.sling.metrics.Counter</span><span class="o">;</span>
+<span class="kn">import</span> <span class="nn">org.apache.sling.metrics.MetricsService</span><span class="o">;</span>
+
+<span class="nd">@Reference</span>
+<span class="kd">private</span> <span class="n">MetricsService</span> <span class="n">metricsService</span><span class="o">;</span>
+
+<span class="kd">private</span> <span class="n">Counter</span> <span class="n">counter</span><span class="o">;</span>
+
+<span class="nd">@Activate</span>
+<span class="kd">private</span> <span class="kt">void</span> <span class="nf">activate</span><span class="o">(){</span>
+ <span class="n">counter</span> <span class="o">=</span> <span class="n">metricsService</span><span class="o">.</span><span class="na">counter</span><span class="o">(</span><span class="s">"sessionCounter"</span><span class="o">);</span>
+<span class="o">}</span>
+
+<span class="kd">public</span> <span class="kt">void</span> <span class="nf">onSessionCreation</span><span class="o">(){</span>
+ <span class="n">counter</span><span class="o">.</span><span class="na">inc</span><span class="o">();</span>
+<span class="o">}</span>
+</pre></div>
+
+
+<p>To make use of <code>MetricService</code></p>
+<ol>
+<li>Get a reference to <code>org.apache.sling.metrics.MetricsService</code></li>
+<li>Initialize the metric e.g. Counter in above case. This avoids
+ any potential lookup cost in critical code paths</li>
+<li>Make use of metric instance to capture require stats</li>
+</ol>
+<p>Refer to <a href="https://dropwizard.github.io/metrics/3.1.0/getting-started/#counters">Metric Getting Started</a> guide to see how various types
+of Metric instances can be used. Note that when using Sling Commons Metric
+bundle class names belong to <code>org.apache.sling.commons.metrics</code> package</p>
+<h2 id="api">API<a class="headerlink" href="#api" title="Permanent link">¶</a></h2>
+<p>Sling Metric bundle provides its own Metric classes which are modelled on
+<a href="http://metrics.dropwizard.io/">Dropwizard Metrics</a> library. The metric interfaces defined by Sling bundle
+only provides methods related to data collection. </p>
+<ul>
+<li><a href="https://github.com/apache/sling/blob/trunk/bundles/commons/metrics/src/main/java/org/apache/sling/commons/metrics/Meter.java">org.apache.sling.commons.metrics.Meter</a> - Similar to <a href="https://dropwizard.github.io/metrics/3.1.0/manual/core/#meters">Dropwizard Meter</a></li>
+<li><a href="https://github.com/apache/sling/blob/trunk/bundles/commons/metrics/src/main/java/org/apache/sling/commons/metrics/Timer.java">org.apache.sling.commons.metrics.Timer</a> - Similar to <a href="https://dropwizard.github.io/metrics/3.1.0/manual/core/#timers">Dropwizard Timer</a></li>
+<li><a href="https://github.com/apache/sling/blob/trunk/bundles/commons/metrics/src/main/java/org/apache/sling/commons/metrics/Counter.java">org.apache.sling.commons.metrics.Counter</a> - Similar to <a href="https://dropwizard.github.io/metrics/3.1.0/manual/core/#counters">Dropwizard Timer</a></li>
+<li><a href="https://github.com/apache/sling/blob/trunk/bundles/commons/metrics/src/main/java/org/apache/sling/commons/metrics/Histogram.java">org.apache.sling.commons.metrics.Histogram</a> - Similar to <a href="https://dropwizard.github.io/metrics/3.1.0/manual/core/#histograms">Dropwizard Timer</a></li>
+</ul>
+<p>Further it provides a <code>MetricService</code> which enables creation of different
+type of Metrics like Meter, Timer, Counter and Histogram</p>
+<h3 id="requirement-of-wrapper-interfaces">Requirement of wrapper interfaces<a class="headerlink" href="#requirement-of-wrapper-interfaces" title="Permanent link">¶</a></h3>
+<ul>
+<li>Abstraction - Provides an abstraction around how metrics are collected and how
+ they are reported and consumed. Most of the code would only be concerned with
+ collecting interesting data. How it gets consumed or reported is implementation
+ detail</li>
+<li>Ability to turnoff stats collection - We can easily turn off data collection
+ by switching to NOOP variant of <code>MetricService</code> in case it starts adding appreciable
+ overhead. Turning on and off can also be done on individual metric basis</li>
+</ul>
+<p>It also allows us to later extend the type of data collected. For e.g. we can also collect
+<a href="https://jackrabbit.apache.org/api/2.6/org/apache/jackrabbit/api/stats/TimeSeries.html">TimerSeries</a> type of data for each metric without modifying the caller logic</p>
+<h3 id="access-to-dropwizard-metrics-api">Access to Dropwizard Metrics API<a class="headerlink" href="#access-to-dropwizard-metrics-api" title="Permanent link">¶</a></h3>
+<p>Sling Metrics bundle also registers the <code>MetricRegistry</code> instance with OSGi service registry.
+The instances registered has a service property <code>name</code> set to <code>sling</code> (so as allow distinguishing
+from any other registered <code>MetricRegistry</code> instance). It can be used to get direct access to Dropwizard
+Metric API if required</p>
+<div class="codehilite"><pre><span class="nd">@Reference</span><span class="o">(</span><span class="n">target</span> <span class="o">=</span> <span class="s">"(name=sling)"</span><span class="o">)</span>
+<span class="kd">private</span> <span class="kd">volatile</span> <span class="n">MetricRegistry</span> <span class="n">dataSource</span><span class="o">;</span>
+</pre></div>
+
+
+<p>Also the wrapper Metric instance can be converted to actual instance via <code>adaptTo</code> calls</p>
+<div class="codehilite"><pre><span class="kn">import</span> <span class="nn">org.apache.sling.commons.metrics.Counter</span>
+
+<span class="n">Counter</span> <span class="n">counter</span> <span class="o">=</span> <span class="n">metricService</span><span class="o">.</span><span class="na">counter</span><span class="o">(</span><span class="s">"login"</span><span class="o">);</span>
+<span class="n">com</span><span class="o">.</span><span class="na">codahale</span><span class="o">.</span><span class="na">metrics</span><span class="o">.</span><span class="na">Counter</span> <span class="o">=</span> <span class="n">counter</span><span class="o">.</span><span class="na">adaptTo</span><span class="o">(</span><span class="n">com</span><span class="o">.</span><span class="na">codahale</span><span class="o">.</span><span class="na">metrics</span><span class="o">.</span><span class="na">Counter</span><span class="o">.</span><span class="na">class</span><span class="o">)</span>
+</pre></div>
+
+
+<h2 id="webconsole-plugin">WebConsole Plugin<a class="headerlink" href="#webconsole-plugin" title="Permanent link">¶</a></h2>
+<p>A Web Console plugin is also provided which is accessible at
+http://localhost:8080/system/console/slingmetrics. It lists down all registered
+metric instances and there state. </p>
+<p><img alt="Metric Plugin" src="/documentation/bundles/metric-web-console.png" /></p>
+<p>The plugin lists all Metric instances from any <code>MetricRegistry</code> instance found in
+the service registry. If the <code>MetricRegistry</code> service has a <code>name</code> property defined
+then that would be prefixed to the Metric names from that registry. This allows
+use of same name in different registry instances.</p>
+<h2 id="installation">Installation<a class="headerlink" href="#installation" title="Permanent link">¶</a></h2>
+<p>Add following Maven dependency to your pom.xml:</p>
+<div class="codehilite"><pre><span class="nt"><dependency></span>
+ <span class="nt"><groupId></span>org.apache.sling<span class="nt"></groupId></span>
+ <span class="nt"><artifactId></span>org.apache.sling.commons.metrics<span class="nt"></artifactId></span>
+ <span class="nt"><version></span>0.0.1-SNAPSHOT<span class="nt"></version></span>
+<span class="nt"></dependency></span>
+</pre></div>
+ <div class="timestamp" style="margin-top: 30px; font-size: 80%; text-align: right;">
+ Rev. 1723490 by chetanm on Thu, 7 Jan 2016 09:26:17 +0000
+ </div>
+ <div class="trademarkFooter">
+ Apache Sling, Sling, Apache, the Apache feather logo, and the Apache Sling project
+ logo are trademarks of The Apache Software Foundation. All other marks mentioned
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+ </div>
+ </div>
+ </body>
+</html>