Author: buildbot
Date: Fri Aug 23 01:58:33 2019
New Revision: 1049204
Log:
Production update by buildbot for cxf
Modified:
websites/production/cxf/content/cache/docs.pageCache
websites/production/cxf/content/docs/using-apache-htrace.html
Modified: websites/production/cxf/content/cache/docs.pageCache
==============================================================================
Binary files - no diff available.
Modified: websites/production/cxf/content/docs/using-apache-htrace.html
==============================================================================
--- websites/production/cxf/content/docs/using-apache-htrace.html (original)
+++ websites/production/cxf/content/docs/using-apache-htrace.html Fri Aug 23
01:58:33 2019
@@ -100,15 +100,7 @@ Apache CXF -- Using Apache HTrace
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Javascript in the HTML macro. This setting can be changed using HTML for
Confluence Configuration. Please see your administrator for
details.</p></div><hr><ul class="alternate"><li><a shape="rect"
href="http://cxf.apache.org/javadoc/latest/";>API 3.2.x (Javadoc)</a></li><li><a
shape="rect" href="http://cxf.apache.org/javadoc/latest-3.1.x/";>API 3.1.x
(Javadoc)</a></li><li><a shape="rect" href="http://cxf.apache.org/";>CXF
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@@ -119,11 +111,11 @@ Apache CXF -- Using Apache HTrace
<!-- Content -->
<div class="wiki-content">
<div id="ConfluenceContent"><p><style type="text/css">/*<![CDATA[*/
-div.rbtoc1546790222248 {padding: 0px;}
-div.rbtoc1546790222248 ul {list-style: disc;margin-left: 0px;}
-div.rbtoc1546790222248 li {margin-left: 0px;padding-left: 0px;}
+div.rbtoc1566525464347 {padding: 0px;}
+div.rbtoc1566525464347 ul {list-style: disc;margin-left: 0px;}
+div.rbtoc1566525464347 li {margin-left: 0px;padding-left: 0px;}
-/*]]>*/</style></p><div class="toc-macro rbtoc1546790222248">
+/*]]>*/</style></p><div class="toc-macro rbtoc1566525464347">
<ul class="toc-indentation"><li><a shape="rect"
href="#UsingApacheHTrace-Overview">Overview</a></li><li><a shape="rect"
href="#UsingApacheHTrace-DistributedTracinginNutshell">Distributed Tracing in
Nutshell</a></li><li><a shape="rect"
href="#UsingApacheHTrace-DistributedTracinginApacheCXFusingApacheHTrace">Distributed
Tracing in Apache CXF using Apache HTrace</a></li><li><a shape="rect"
href="#UsingApacheHTrace-ConfiguringClientconfigure.client">Configuring
Client</a>
<ul class="toc-indentation"><li><a shape="rect"
href="#UsingApacheHTrace-Configuringtracingheadernames">Configuring tracing
header names</a></li></ul>
</li><li><a shape="rect"
href="#UsingApacheHTrace-ConfiguringServerconfigure.server">Configuring
Server</a>
@@ -131,7 +123,7 @@ div.rbtoc1546790222248 li {margin-left:
</li><li><a shape="rect"
href="#UsingApacheHTrace-DistributedTracingInAction:UsageScenarios">Distributed
Tracing In Action: Usage Scenarios</a>
<ul class="toc-indentation"><li><a shape="rect"
href="#UsingApacheHTrace-Example#1:ClientandServerwithdefaultdistributedtracingconfigured">Example
#1: Client and Server with default distributed tracing
configured</a></li><li><a shape="rect"
href="#UsingApacheHTrace-Example#2:ClientandServerwithnestedtrace">Example #2:
Client and Server with nested trace</a></li><li><a shape="rect"
href="#UsingApacheHTrace-Example#3:ClientandServertracewithtimeline">Example
#3: Client and Server trace with timeline</a></li><li><a shape="rect"
href="#UsingApacheHTrace-Example#4:ClientandServerwithannotatedtrace(key/value)">Example
#4: Client and Server with annotated trace (key/value)</a></li><li><a
shape="rect"
href="#UsingApacheHTrace-Example#5:ClientandServerwithparalleltrace(involvingthreadpools)">Example
#5: Client and Server with parallel trace (involving thread
pools)</a></li><li><a shape="rect"
href="#UsingApacheHTrace-Example#6:ClientandServerwithasynchronousJAX-RSservice(server-side)">Exampl
e #6: Client and Server with asynchronous JAX-RS service
(server-side)</a></li><li><a shape="rect"
href="#UsingApacheHTrace-Example#7:ClientandServerwithasynchronousinvocation(client-side)">Example
#7: Client and Server with asynchronous invocation (client-side)</a></li></ul>
</li><li><a shape="rect"
href="#UsingApacheHTrace-DistributedTracingApacheHTraceandJAX-WSsupport">Distributed
Tracing Apache HTrace and JAX-WS support</a></li><li><a shape="rect"
href="#UsingApacheHTrace-PropagatingTraceDetailsToLogs">Propagating Trace
Details To Logs</a></li><li><a shape="rect"
href="#UsingApacheHTrace-AccessingApacheHTraceAPIs">Accessing Apache HTrace
APIs</a></li><li><a shape="rect" href="#UsingApacheHTrace-FutureWork">Future
Work</a></li></ul>
-</div><div class="confluence-information-macro
confluence-information-macro-warning"><span class="aui-icon aui-icon-small
aui-iconfont-error confluence-information-macro-icon"></span><div
class="confluence-information-macro-body"><p>The <a shape="rect"
class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a> project
has retired on<strong> 2018-04-11</strong> and is not developed anymore. The
Apache CXF will no longer provide the <a shape="rect" class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a>
integration, staring from <strong>3.3.0</strong>
release. </p></div></div><h1
id="UsingApacheHTrace-Overview">Overview</h1><p><a shape="rect"
class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a> is a
tracing framework intended for use with distributed systems written in java.
Since version <strong>3.1.3</strong>, Apache CXF fully supports integration
with <a shape="rect"
class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a>, both on
client side and server side. This section gives a complete overview on how
distributed tracing support is supported in JAX-RS applications built on top of
Apache CXF.</p><h1
id="UsingApacheHTrace-DistributedTracinginNutshell">Distributed Tracing in
Nutshell</h1><p>Distributed tracing, first described by Google in <a
shape="rect" class="external-link"
href="http://research.google.com/pubs/pub36356.html"; rel="nofollow">Dapper, a
Large-Scale Distributed Systems Tracing Infrastructure</a> paper became
increasingly important topic these days. With microservices (aka SOA) gaining
more and more adoption, the typical applications are built using dozens or even
hundreds of small, distributed pieces. The end-to-end traceability of the
requests (or any kind of work performed on user's behalf) is hard task to
accomplish, particularly taking into account asyncronous or/and concurrent
invocations
. <a shape="rect" class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a> is
inspired by <a shape="rect" class="external-link"
href="http://research.google.com/pubs/pub36356.html"; rel="nofollow">Dapper, a
Large-Scale Distributed Systems Tracing Infrastructure</a> paper and
essentially is a full-fledged distributed tracing framework.</p><p>Distributed
tracing is additional instrumentation layer on top of new or existing
applications. In terms of distributed tracing, <strong>span</strong> represents
a basic unit of work. For example, executing database query is a
<strong>span</strong>. <strong>Spans</strong> are identified by a unique
128-bit ID. <strong>Spans</strong> also have other data, such as
<strong>descriptions</strong>, <strong>timelines</strong>,<strong> key-value
annotations</strong>, the <strong>ID</strong> of the <strong>span</strong> that
caused them (parent), and <strong>process/tracer</strong> ID’s (normally
IP address and pro
cess name). Spans are started and stopped, and they keep track of their timing
information. Once <strong>span</strong> is created, it should be stopped at
some point in the future. In turn, <strong>trace</strong> is a set of spans
forming a tree-like structure. For example, if you are running a JAX-RS
service, a trace might be formed by a <strong>PUT</strong> request and
downstream work.</p><p>From implementation perspective, and in context of Java
applications, <strong>spans</strong> are attached to their threads (in general,
thread which created the <strong>span</strong> should close it). However it is
possible to transfer <strong>spans</strong> from thread to thread in order to
model a complex execution flows. It is also possible to have many
<strong>spans</strong> in the same thread, as long as they are properly created
and closed. In the next sections we are going to see the examples of
that.</p><p>Another two important concepts in context of distributed tracing
are <strong>spa
n receivers</strong> and <strong>samplers</strong>. Essentially, all spans
(including start/stop time, key/value annotations, timelines, ..) should be
persisted (or collected) somewhere. <strong>Span receiver</strong> is a
collector within a process that is the destination of <strong>spans</strong>
when a trace is running (it could be a console, local file, data store, ...).
<a shape="rect" class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a> provides
span receivers for <a shape="rect" class="external-link"
href="http://hbase.apache.org";>Apache HBase</a>, <a shape="rect"
class="external-link" href="https://flume.apache.org/";>Apache Flume</a> and <a
shape="rect" class="external-link" href="http://zipkin.io/";
rel="nofollow">Twitter Zipkin</a>. From other side, <strong>samplers</strong>
allow to control the frequency of the tracing (all the time, never, probability
driven, ...). Using the <strong>sampler</strong> is the way to minimize tracing
ov
erhead (or just amount of traces) by limiting them to particular
conditions.</p><h1
id="UsingApacheHTrace-DistributedTracinginApacheCXFusingApacheHTrace">Distributed
Tracing in Apache CXF using Apache HTrace</h1><p><a shape="rect"
href="http://cxf.apache.org/";>Apache CXF</a> is a very popular framework for
building services and web APIs. No doubts, it is going to play even more
important role in context of microservices architecture letting developers to
quickly build and deploy individual JAX-RS/JAX-WS services. As it was just
mentioned before, distributed tracing is an essential technique to monitor the
application as whole, breaking the request to individual service traces as it
goes through and crosses the boundaries of threads, processes and
machines.</p><p>The current integration of distributed tracing in <a
shape="rect" href="http://cxf.apache.org/";>Apache CXF</a> supports <a
shape="rect" class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace
</a> (<strong>4.x+</strong> release branch) only in JAX-RS 2.x applications.
From high-level prospective, it consists of three main parts:</p><ul
style="list-style-type: square;"><li><strong>TracerContext</strong> (injectable
through <strong>@Context</strong>
annotation)</li><li><strong>HTraceProvider</strong> (server-side JAX-RS
provider) and <strong>HTraceClientProvider</strong> (client-side JAX-RS
provider)</li><li><strong>HTraceFeature</strong> (server-side <a shape="rect"
href="http://cxf.apache.org/";>Apache CXF</a> feature to simplify <a
shape="rect" class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a>
configuration and integration)</li></ul><p><a shape="rect"
href="http://cxf.apache.org/";>Apache CXF</a> uses HTTP headers to hand off
tracing context from the client to the service and from the service to service.
Those headers are used internally by <strong>HTraceProvider</strong> and
<strong>HTraceClientProvider</strong>, but are configu
rable. The default header names are declared in the TracerHeaders
class:</p><ul style="list-style-type: square;"><li><strong>X-Span-Id</strong>:
contains a current span ID</li></ul><p>By default,
<strong>HTraceProvider</strong> will try to pass the currently active
<strong>span</strong> through HTTP headers on each service invocation. If there
is no active spans, the new span will be created and passed through HTTP
headers on per-invocation basis. Essentially, just registering the
<strong>HTraceClientProvider</strong> on the client
and <strong>HTraceProvider</strong> on the server is enough to have
tracing context to be properly passed everywhere. The only configuration part
which is necessary are <strong>span receiver(s)</strong> and
<strong>sampler</strong>(s).</p><p>It is also worth to mention the way <a
shape="rect" href="http://cxf.apache.org/";>Apache CXF</a> attaches the
description to <strong>spans</strong>. With regards to the client integration,
the description becomes
a full URL being invoked prefixed by HTTP method, for example: <strong>GET
</strong><a shape="rect" class="external-link"
href="http://localhost:8282/books";
rel="nofollow"><strong>http://localhost:8282</strong>/books</a>. On the server
side integration, the description becomes a relative JAX-RS resource path
prefixed by HTTP method, f.e.: <strong>GET books, POST book/123</strong></p><h1
id="UsingApacheHTrace-ConfiguringClientconfigure.client">Configuring Client
<span class="confluence-anchor-link"
id="UsingApacheHTrace-configure.client"></span></h1><p>There are a couple of
ways the JAX-RS client could be configured, depending on the client
implementation. <a shape="rect" href="http://cxf.apache.org/";>Apache CXF</a>
provides its own <strong>WebClient</strong> which could be configured just like
that (in future versions, there would be a simpler ways to do that using client
specific features):</p><div class="code panel pdl" style="border-width:
1px;"><div class="codeContent panelCont
ent pdl">
+</div><div class="confluence-information-macro
confluence-information-macro-warning"><span class="aui-icon aui-icon-small
aui-iconfont-error confluence-information-macro-icon"></span><div
class="confluence-information-macro-body"><p>The <a shape="rect"
class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a> project
has retired on<strong> 2018-04-11</strong> and is not developed anymore. The
Apache CXF retired the <a shape="rect" class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a>
integration, starting from <strong>3.3.0</strong>
release. </p></div></div><h1
id="UsingApacheHTrace-Overview">Overview</h1><p><a shape="rect"
class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a> is a
tracing framework intended for use with distributed systems written in java.
Since version <strong>3.1.3</strong>, Apache CXF fully supports integration
with <a shape="rect" class="externa
l-link" href="http://htrace.incubator.apache.org/index.html";>Apache
HTrace</a>, both on client side and server side. This section gives a complete
overview on how distributed tracing support is supported in JAX-RS applications
built on top of Apache CXF.</p><h1
id="UsingApacheHTrace-DistributedTracinginNutshell">Distributed Tracing in
Nutshell</h1><p>Distributed tracing, first described by Google in <a
shape="rect" class="external-link"
href="http://research.google.com/pubs/pub36356.html"; rel="nofollow">Dapper, a
Large-Scale Distributed Systems Tracing Infrastructure</a> paper became
increasingly important topic these days. With microservices (aka SOA) gaining
more and more adoption, the typical applications are built using dozens or even
hundreds of small, distributed pieces. The end-to-end traceability of the
requests (or any kind of work performed on user's behalf) is hard task to
accomplish, particularly taking into account asyncronous or/and concurrent
invocations. <a shape="re
ct" class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a> is
inspired by <a shape="rect" class="external-link"
href="http://research.google.com/pubs/pub36356.html"; rel="nofollow">Dapper, a
Large-Scale Distributed Systems Tracing Infrastructure</a> paper and
essentially is a full-fledged distributed tracing framework.</p><p>Distributed
tracing is additional instrumentation layer on top of new or existing
applications. In terms of distributed tracing, <strong>span</strong> represents
a basic unit of work. For example, executing database query is a
<strong>span</strong>. <strong>Spans</strong> are identified by a unique
128-bit ID. <strong>Spans</strong> also have other data, such as
<strong>descriptions</strong>, <strong>timelines</strong>,<strong> key-value
annotations</strong>, the <strong>ID</strong> of the <strong>span</strong> that
caused them (parent), and <strong>process/tracer</strong> ID’s (normally
IP address and process name). Sp
ans are started and stopped, and they keep track of their timing information.
Once <strong>span</strong> is created, it should be stopped at some point in
the future. In turn, <strong>trace</strong> is a set of spans forming a
tree-like structure. For example, if you are running a JAX-RS service, a trace
might be formed by a <strong>PUT</strong> request and downstream
work.</p><p>From implementation perspective, and in context of Java
applications, <strong>spans</strong> are attached to their threads (in general,
thread which created the <strong>span</strong> should close it). However it is
possible to transfer <strong>spans</strong> from thread to thread in order to
model a complex execution flows. It is also possible to have many
<strong>spans</strong> in the same thread, as long as they are properly created
and closed. In the next sections we are going to see the examples of
that.</p><p>Another two important concepts in context of distributed tracing
are <strong>span receivers</s
trong> and <strong>samplers</strong>. Essentially, all spans (including
start/stop time, key/value annotations, timelines, ..) should be persisted (or
collected) somewhere. <strong>Span receiver</strong> is a collector within a
process that is the destination of <strong>spans</strong> when a trace is
running (it could be a console, local file, data store, ...). <a shape="rect"
class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a> provides
span receivers for <a shape="rect" class="external-link"
href="http://hbase.apache.org";>Apache HBase</a>, <a shape="rect"
class="external-link" href="https://flume.apache.org/";>Apache Flume</a> and <a
shape="rect" class="external-link" href="http://zipkin.io/";
rel="nofollow">Twitter Zipkin</a>. From other side, <strong>samplers</strong>
allow to control the frequency of the tracing (all the time, never, probability
driven, ...). Using the <strong>sampler</strong> is the way to minimize tracing
overhead (or jus
t amount of traces) by limiting them to particular conditions.</p><h1
id="UsingApacheHTrace-DistributedTracinginApacheCXFusingApacheHTrace">Distributed
Tracing in Apache CXF using Apache HTrace</h1><p><a shape="rect"
href="http://cxf.apache.org/";>Apache CXF</a> is a very popular framework for
building services and web APIs. No doubts, it is going to play even more
important role in context of microservices architecture letting developers to
quickly build and deploy individual JAX-RS/JAX-WS services. As it was just
mentioned before, distributed tracing is an essential technique to monitor the
application as whole, breaking the request to individual service traces as it
goes through and crosses the boundaries of threads, processes and
machines.</p><p>The current integration of distributed tracing in <a
shape="rect" href="http://cxf.apache.org/";>Apache CXF</a> supports <a
shape="rect" class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a> (<strong>
4.x+</strong> release branch) only in JAX-RS 2.x applications. From high-level
prospective, it consists of three main parts:</p><ul style="list-style-type:
square;"><li><strong>TracerContext</strong> (injectable through
<strong>@Context</strong> annotation)</li><li><strong>HTraceProvider</strong>
(server-side JAX-RS provider) and <strong>HTraceClientProvider</strong>
(client-side JAX-RS provider)</li><li><strong>HTraceFeature</strong>
(server-side <a shape="rect" href="http://cxf.apache.org/";>Apache CXF</a>
feature to simplify <a shape="rect" class="external-link"
href="http://htrace.incubator.apache.org/index.html";>Apache HTrace</a>
configuration and integration)</li></ul><p><a shape="rect"
href="http://cxf.apache.org/";>Apache CXF</a> uses HTTP headers to hand off
tracing context from the client to the service and from the service to service.
Those headers are used internally by <strong>HTraceProvider</strong> and
<strong>HTraceClientProvider</strong>, but are configurable. The def
ault header names are declared in the TracerHeaders class:</p><ul
style="list-style-type: square;"><li><strong>X-Span-Id</strong>: contains a
current span ID</li></ul><p>By default, <strong>HTraceProvider</strong> will
try to pass the currently active <strong>span</strong> through HTTP headers on
each service invocation. If there is no active spans, the new span will be
created and passed through HTTP headers on per-invocation basis. Essentially,
just registering the <strong>HTraceClientProvider</strong> on the client
and <strong>HTraceProvider</strong> on the server is enough to have
tracing context to be properly passed everywhere. The only configuration part
which is necessary are <strong>span receiver(s)</strong> and
<strong>sampler</strong>(s).</p><p>It is also worth to mention the way <a
shape="rect" href="http://cxf.apache.org/";>Apache CXF</a> attaches the
description to <strong>spans</strong>. With regards to the client integration,
the description becomes a full URL be
ing invoked prefixed by HTTP method, for example: <strong>GET </strong><a
shape="rect" class="external-link" href="http://localhost:8282/books";
rel="nofollow"><strong>http://localhost:8282</strong>/books</a>. On the server
side integration, the description becomes a relative JAX-RS resource path
prefixed by HTTP method, f.e.: <strong>GET books, POST book/123</strong></p><h1
id="UsingApacheHTrace-ConfiguringClientconfigure.client">Configuring Client
<span class="confluence-anchor-link"
id="UsingApacheHTrace-configure.client"></span></h1><p>There are a couple of
ways the JAX-RS client could be configured, depending on the client
implementation. <a shape="rect" href="http://cxf.apache.org/";>Apache CXF</a>
provides its own <strong>WebClient</strong> which could be configured just like
that (in future versions, there would be a simpler ways to do that using client
specific features):</p><div class="code panel pdl" style="border-width:
1px;"><div class="codeContent panelContent pdl">
<pre class="brush: java; gutter: false; theme: Default">final Map<String,
String> properties = new HashMap<String, String>();
properties.put(Tracer.SPAN_RECEIVER_CLASSES_KEY, ...);
properties.put(Tracer.SAMPLER_CLASSES_KEY, ...);
![http://www.apache.org/events/current-event-125x125.png"](http://www.apache.org/events/current-event-125x125.png"){kind=link}