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<h2 class="title"><a id="java-codec-plugin"></a>How to write a Java codec plugin<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h2>
</div></div></div>
<div class="note admon">
<div class="icon"></div>
<div class="admon_content">
<p>Java codecs are currently supported only for Java input and output plugins. They will not work with Ruby
input or output plugins.</p>
</div>
</div>
<p>To develop a new Java codec for Logstash, you write a new Java class that
conforms to the Logstash Java Codecs API, package it, and install it with the
logstash-plugin utility. We’ll go through each of those steps.</p>
<h3><a id="_set_up_your_environment_2"></a>Set up your environment<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h3>
<h4><a id="_copy_the_example_repo_2"></a>Copy the example repo<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h4>
<p>Start by copying the <a href="https://github.com/logstash-plugins/logstash-codec-java_codec_example" class="ulink" target="_top">example codec plugin</a>. The plugin API is currently part of the
Logstash codebase so you must have a local copy of that available. You can
obtain a copy of the Logstash codebase with the following <code class="literal">git</code> command:</p>
<div class="pre_wrapper lang-shell">
<pre class="programlisting prettyprint lang-shell">git clone --branch <branch_name> --single-branch https://github.com/elastic/logstash.git <target_folder></pre>
</div>
<p>The <code class="literal">branch_name</code> should correspond to the version of Logstash containing the
preferred revision of the Java plugin API.</p>
<div class="note admon">
<div class="icon"></div>
<div class="admon_content">
<p>The GA version of the Java plugin API is available in the <code class="literal">7.1</code>
and later branches of the Logstash codebase.</p>
</div>
</div>
<p>Specify the <code class="literal">target_folder</code> for your local copy of the Logstash codebase. If you
do not specify <code class="literal">target_folder</code>, it defaults to a new folder called <code class="literal">logstash</code>
under your current folder.</p>
<h4><a id="_generate_the_jar_file_2"></a>Generate the .jar file<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h4>
<p>After you have obtained a copy of the appropriate revision of the Logstash
codebase, you need to compile it to generate the .jar file containing the Java
plugin API. From the root directory of your Logstash codebase ($LS_HOME), you
can compile it with <code class="literal">./gradlew assemble</code> (or <code class="literal">gradlew.bat assemble</code> if you’re
running on Windows). This should produce the
<code class="literal">$LS_HOME/logstash-core/build/libs/logstash-core-x.y.z.jar</code> where <code class="literal">x</code>, <code class="literal">y</code>, and
<code class="literal">z</code> refer to the version of Logstash.</p>
<p>After you have successfully compiled Logstash, you need to tell your Java plugin
where to find the <code class="literal">logstash-core-x.y.z.jar</code> file. Create a new file named
<code class="literal">gradle.properties</code> in the root folder of your plugin project. That file should
have a single line:</p>
<div class="pre_wrapper lang-txt">
<pre class="programlisting prettyprint lang-txt">LOGSTASH_CORE_PATH=<target_folder>/logstash-core</pre>
</div>
<p>where <code class="literal">target_folder</code> is the root folder of your local copy of the Logstash codebase.</p>
<h3><a id="_code_the_plugin_2"></a>Code the plugin<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h3>
<p>The example codec plugin decodes messages separated by a configurable delimiter
and encodes messages by writing their string representation separated by a
delimiter. For example, if the codec were configured with <code class="literal">/</code> as the delimiter,
the input text <code class="literal">event1/event2/</code> would be decoded into two separate events with
<code class="literal">message</code> fields of <code class="literal">event1</code> and <code class="literal">event2</code>, respectively. Note that this is only
an example codec and does not cover all the edge cases that a production-grade
codec should cover.</p>
<p>Let’s look at the main class in that codec filter:</p>
<div class="pre_wrapper lang-java">
<pre class="programlisting prettyprint lang-java">@LogstashPlugin(name="java_codec_example")
public class JavaCodecExample implements Codec {
public static final PluginConfigSpec<String> DELIMITER_CONFIG =
PluginConfigSpec.stringSetting("delimiter", ",");
private final String id;
private final String delimiter;
public JavaCodecExample(final Configuration config, final Context context) {
this(config.get(DELIMITER_CONFIG));
}
private JavaCodecExample(String delimiter) {
this.id = UUID.randomUUID().toString();
this.delimiter = delimiter;
}
@Override
public void decode(ByteBuffer byteBuffer, Consumer<Map<String, Object>> consumer) {
// a not-production-grade delimiter decoder
byte[] byteInput = new byte[byteBuffer.remaining()];
byteBuffer.get(byteInput);
if (byteInput.length > 0) {
String input = new String(byteInput);
String[] split = input.split(delimiter);
for (String s : split) {
Map<String, Object> map = new HashMap<>();
map.put("message", s);
consumer.accept(map);
}
}
}
@Override
public void flush(ByteBuffer byteBuffer, Consumer<Map<String, Object>> consumer) {
// if the codec maintains any internal state such as partially-decoded input, this
// method should flush that state along with any additional input supplied in
// the ByteBuffer
decode(byteBuffer, consumer); // this is a simplistic implementation
}
@Override
public void encode(Event event, OutputStream outputStream) throws IOException {
outputStream.write((event.toString() + delimiter).getBytes(Charset.defaultCharset()));
}
@Override
public Collection<PluginConfigSpec<?>> configSchema() {
// should return a list of all configuration options for this plugin
return Collections.singletonList(DELIMITER_CONFIG);
}
@Override
public Codec cloneCodec() {
return new JavaCodecExample(this.delimiter);
}
@Override
public String getId() {
return this.id;
}
}</pre>
</div>
<p>Let’s step through and examine each part of that class.</p>
<h4><a id="_class_declaration_6"></a>Class declaration<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h4>
<div class="pre_wrapper lang-java">
<pre class="programlisting prettyprint lang-java">@LogstashPlugin(name="java_codec_example")
public class JavaCodecExample implements Codec {</pre>
</div>
<p>Notes about the class declaration:</p>
<div class="ulist itemizedlist">
<ul class="itemizedlist">
<li class="listitem">
<p>All Java plugins must be annotated with the <code class="literal">@LogstashPlugin</code> annotation. Additionally:</p>
<div class="ulist itemizedlist">
<ul class="itemizedlist">
<li class="listitem">
The <code class="literal">name</code> property of the annotation must be supplied and defines the name of the plugin as it will be used
in the Logstash pipeline definition. For example, this codec would be referenced in the codec section of the
an appropriate input or output in the Logstash pipeline defintion as <code class="literal">codec => java_codec_example { }</code>
</li>
<li class="listitem">
The value of the <code class="literal">name</code> property must match the name of the class excluding casing and underscores.
</li>
</ul>
</div>
</li>
<li class="listitem">
The class must implement the <code class="literal">co.elastic.logstash.api.Codec</code> interface.
</li>
<li class="listitem">
Java plugins may not be created in the <code class="literal">org.logstash</code> or <code class="literal">co.elastic.logstash</code> packages to prevent potential
clashes with classes in Logstash itself.
</li>
</ul>
</div>
<h5><a id="_plugin_settings_2"></a>Plugin settings<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h5>
<p>The snippet below contains both the setting definition and the method referencing it:</p>
<div class="pre_wrapper lang-java">
<pre class="programlisting prettyprint lang-java">public static final PluginConfigSpec<String> DELIMITER_CONFIG =
PluginConfigSpec.stringSetting("delimiter", ",");
@Override
public Collection<PluginConfigSpec<?>> configSchema() {
return Collections.singletonList(DELIMITER_CONFIG);
}</pre>
</div>
<p>The <code class="literal">PluginConfigSpec</code> class allows developers to specify the settings that a
plugin supports complete with setting name, data type, deprecation status,
required status, and default value. In this example, the <code class="literal">delimiter</code> setting
defines the delimiter on which the codec will split events. It is not a required
setting and if it is not explicitly set, its default value will be <code class="literal">,</code>.</p>
<p>The <code class="literal">configSchema</code> method must return a list of all settings that the plugin
supports. The Logstash execution engine will validate that all required
settings are present and that no unsupported settings are present.</p>
<h5><a id="_constructor_and_initialization_2"></a>Constructor and initialization<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h5>
<div class="pre_wrapper lang-java">
<pre class="programlisting prettyprint lang-java">private final String id;
private final String delimiter;
public JavaCodecExample(final Configuration config, final Context context) {
this(config.get(DELIMITER_CONFIG));
}
private JavaCodecExample(String delimiter) {
this.id = UUID.randomUUID().toString();
this.delimiter = delimiter;
}</pre>
</div>
<p>All Java codec plugins must have a constructor taking a <code class="literal">Configuration</code> and
<code class="literal">Context</code> argument. This is the constructor that will be used to instantiate
them at runtime. The retrieval and validation of all plugin settings should
occur in this constructor. In this example, the delimiter to be used for
delimiting events is retrieved from its setting and stored in a local variable
so that it can be used later in the <code class="literal">decode</code> and <code class="literal">encode</code> methods. The codec’s
ID is initialized to a random UUID (as should be done for most codecs), and a
local <code class="literal">encoder</code> variable is initialized to encode and decode with a specified
character set.</p>
<p>Any additional initialization may occur in the constructor as well. If there are
any unrecoverable errors encountered in the configuration or initialization of
the codec plugin, a descriptive exception should be thrown. The exception will
be logged and will prevent Logstash from starting.</p>
<h4><a id="_codec_methods"></a>Codec methods<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h4>
<div class="pre_wrapper lang-java">
<pre class="programlisting prettyprint lang-java">@Override
public void decode(ByteBuffer byteBuffer, Consumer<Map<String, Object>> consumer) {
// a not-production-grade delimiter decoder
byte[] byteInput = new byte[byteBuffer.remaining()];
byteBuffer.get(byteInput);
if (byteInput.length > 0) {
String input = new String(byteInput);
String[] split = input.split(delimiter);
for (String s : split) {
Map<String, Object> map = new HashMap<>();
map.put("message", s);
consumer.accept(map);
}
}
}
@Override
public void flush(ByteBuffer byteBuffer, Consumer<Map<String, Object>> consumer) {
// if the codec maintains any internal state such as partially-decoded input, this
// method should flush that state along with any additional input supplied in
// the ByteBuffer
decode(byteBuffer, consumer); // this is a simplistic implementation
}
@Override
public void encode(Event event, OutputStream outputStream) throws IOException {
outputStream.write((event.toString() + delimiter).getBytes(Charset.defaultCharset()));
}</pre>
</div>
<p>The <code class="literal">decode</code>, <code class="literal">flush</code>, and <code class="literal">encode</code> methods provide the core functionality of
the codec. Codecs may be used by inputs to decode a sequence or stream of bytes
into events or by outputs to encode events into a sequence of bytes.</p>
<p>The <code class="literal">decode</code> method decodes events from the specified <code class="literal">ByteBuffer</code> and passes
them to the provided <code class="literal">Consumer</code>. The input must provide a <code class="literal">ByteBuffer</code> that is
ready for reading with <code class="literal">byteBuffer.position()</code> indicating the next position to
read and <code class="literal">byteBuffer.limit()</code> indicating the first byte in the buffer that is
not safe to read. Codecs must ensure that <code class="literal">byteBuffer.position()</code> reflects the
last-read position before returning control to the input. The input is then
responsible for returning the buffer to write mode via either
<code class="literal">byteBuffer.clear()</code> or <code class="literal">byteBuffer.compact()</code> before resuming writes. In the
example above, the <code class="literal">decode</code> method simply splits the incoming byte stream on the
specified delimiter. A production-grade codec such as
<a href="https://github.com/elastic/logstash/blob/master/logstash-core/src/main/java/org/logstash/plugins/codecs/Line.java" class="ulink" target="_top"><code class="literal">java-line</code></a>
would not make the simplifying assumption that the end of the supplied byte
stream corresponded with the end of an event.</p>
<p>Events should be constructed as instances of <code class="literal">Map<String, Object></code> and pushed into the event pipeline via the
<code class="literal">Consumer<Map<String, Object>>.accept()</code> method. To reduce allocations and GC pressure, codecs may reuse the same
map instance by modifying its fields between calls to <code class="literal">Consumer<Map<String, Object>>.accept()</code> because the event
pipeline will create events based on a copy of the map’s data.</p>
<p>The <code class="literal">flush</code> method works in coordination with the <code class="literal">decode</code> method to decode all
remaining events from the specified <code class="literal">ByteBuffer</code> along with any internal state
that may remain after previous calls to the <code class="literal">decode</code> method. As an example of
internal state that a codec might maintain, consider an input stream of bytes
<code class="literal">event1/event2/event3</code> with a delimiter of <code class="literal">/</code>. Due to buffering or other
reasons, the input might supply a partial stream of bytes such as <code class="literal">event1/eve</code>
to the codec’s <code class="literal">decode</code> method. In this case, the codec could save the beginning
three characters <code class="literal">eve</code> of the second event rather than assuming that the
supplied byte stream ends on an event boundary. If the next call to <code class="literal">decode</code>
supplied the <code class="literal">nt2/ev</code> bytes, the codec would prepend the saved <code class="literal">eve</code> bytes to
produce the full <code class="literal">event2</code> event and then save the remaining <code class="literal">ev</code> bytes for
decoding when the remainder of the bytes for that event were supplied. A call to
<code class="literal">flush</code> signals the codec that the supplied bytes represent the end of an event
stream and all remaining bytes should be decoded to events. The <code class="literal">flush</code> example
above is a simplistic implementation that does not maintain any state about
partially-supplied byte streams across calls to <code class="literal">decode</code>.</p>
<p>The <code class="literal">encode</code> method encodes an event into a sequence of bytes and writes it into
the specified <code class="literal">OutputStream</code>. Because a single codec instance is shared across
all pipeline workers in the output stage of the Logstash pipeline, codecs should
<em>not</em> retain state across calls to their <code class="literal">encode</code> methods.</p>
<h4><a id="_clonecodec_method"></a>cloneCodec method<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h4>
<div class="pre_wrapper lang-java">
<pre class="programlisting prettyprint lang-java">@Override
public Codec cloneCodec() {
return new JavaCodecExample(this.delimiter);
}</pre>
</div>
<p>The <code class="literal">cloneCodec</code> method should return an identical instance of the codec with the exception of its ID. Because codecs
may be stateful across calls to their <code class="literal">decode</code> methods, input plugins that are multi-threaded should use a separate
instance of each codec via the <code class="literal">cloneCodec</code> method for each of their threads. Because a single codec instance is shared
across all pipeline workers in the output stage of the Logstash pipeline, codecs should <em>not</em> retain state across calls
to their <code class="literal">encode</code> methods. In the example above, the codec is cloned with the same delimiter but a different ID.</p>
<h4><a id="_getid_method_2"></a>getId method<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h4>
<div class="pre_wrapper lang-java">
<pre class="programlisting prettyprint lang-java">@Override
public String getId() {
return id;
}</pre>
</div>
<p>For codec plugins, the <code class="literal">getId</code> method should always return the id that was set at instantiation time. This is typically
an UUID.</p>
<h4><a id="_unit_tests_2"></a>Unit tests<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h4>
<p>Lastly, but certainly not least importantly, unit tests are strongly encouraged.
The example codec plugin includes an
<a href="https://github.com/logstash-plugins/logstash-codec-java_codec_example/blob/master/src/test/java/org/logstash/javaapi/JavaCodecExampleTest.java" class="ulink" target="_top">example unit
test</a> that you can use as a template for your own.</p>
<h3><a id="_package_and_deploy_2"></a>Package and deploy<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h3>
<p>Java plugins are packaged as Ruby gems for dependency management and
interoperability with Ruby plugins. Once they are packaged as gems, they may
be installed with the <code class="literal">logstash-plugin</code> utility just as Ruby plugins are.
Because no knowledge of Ruby or its toolchain should be required for Java
plugin development, the procedure for packaging Java plugins as Ruby gems
has been automated through a custom task in the Gradle build file provided
with the example Java plugins. The following sections describe how to
configure and execute that packaging task as well as how to install the
packaged Java plugin in Logstash.</p>
<h4><a id="_configuring_the_gradle_packaging_task_2"></a>Configuring the Gradle packaging task<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h4>
<p>The following section appears near the top of the <code class="literal">build.gradle</code> file supplied
with the example Java plugins:</p>
<div class="pre_wrapper lang-java">
<pre class="programlisting prettyprint lang-java">// ===========================================================================
// plugin info
// ===========================================================================
group 'org.logstashplugins' // must match the package of the main plugin class
version "${file("VERSION").text.trim()}" // read from required VERSION file
description = "Example Java filter implementation"
pluginInfo.licenses = ['Apache-2.0'] // list of SPDX license IDs
pluginInfo.longDescription = "This gem is a Logstash plugin required to be installed on top of the Logstash core pipeline using \$LS_HOME/bin/logstash-plugin install gemname. This gem is not a stand-alone program"
pluginInfo.authors = ['Elasticsearch']
pluginInfo.email = ['[email protected]']
pluginInfo.homepage = "http://www.elastic.co/guide/en/logstash/current/index.html"
pluginInfo.pluginType = "filter"
pluginInfo.pluginClass = "JavaFilterExample"
pluginInfo.pluginName = "java_filter_example"
// ===========================================================================</pre>
</div>
<p>You should configure the values above for your plugin.</p>
<div class="ulist itemizedlist">
<ul class="itemizedlist">
<li class="listitem">
The <code class="literal">version</code> value will be automatically read from the <code class="literal">VERSION</code> file in the
root of your plugin’s codebase.
</li>
<li class="listitem">
<code class="literal">pluginInfo.pluginType</code> should be set to one of <code class="literal">input</code>, <code class="literal">filter</code>, <code class="literal">codec</code>,
or <code class="literal">output</code>.
</li>
<li class="listitem">
<code class="literal">pluginInfo.pluginName</code> must match the name specified on the <code class="literal">@LogstashPlugin</code>
annotation on the main plugin class. The Gradle packaging task will validate
that and return an error if they do not match.
</li>
</ul>
</div>
<h4><a id="_running_the_gradle_packaging_task_2"></a>Running the Gradle packaging task<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h4>
<p>Several Ruby source files along with a <code class="literal">gemspec</code> file and a <code class="literal">Gemfile</code> are
required to package the plugin as a Ruby gem. These Ruby files are used only
for defining the Ruby gem structure or at Logstash startup time to register
the Java plugin. They are not used during runtime event processing. The
Gradle packaging task automatically generates all of these files based on
the values configured in the section above.</p>
<p>You run the Gradle packaging task with the following command:</p>
<div class="pre_wrapper lang-shell">
<pre class="programlisting prettyprint lang-shell">./gradlew gem</pre>
</div>
<p>For Windows platforms: Substitute <code class="literal">gradlew.bat</code> for <code class="literal">./gradlew</code> as appropriate in the command.</p>
<p>That task will produce a gem file in the root directory of your
plugin’s codebase with the name <code class="literal">logstash-{plugintype}-<pluginName>-<version>.gem</code></p>
<h4><a id="_installing_the_java_plugin_in_logstash_2"></a>Installing the Java plugin in Logstash<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h4>
<p>After you have packaged your Java plugin as a Ruby gem, you can install it in
Logstash with this command:</p>
<div class="pre_wrapper lang-shell">
<pre class="programlisting prettyprint lang-shell">bin/logstash-plugin install --no-verify --local /path/to/javaPlugin.gem</pre>
</div>
<p>For Windows platforms: Substitute backslashes for forward slashes as appropriate in the command.</p>
<h3><a id="_run_logstash_with_the_java_codec_plugin"></a>Run Logstash with the Java codec plugin<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h3>
<p>To test the plugin, start Logstash with:</p>
<div class="pre_wrapper lang-java">
<pre class="programlisting prettyprint lang-java">echo "foo,bar" | bin/logstash -e 'input { java_stdin { codec => java_codec_example } } }'</pre>
</div>
<div class="note admon">
<div class="icon"></div>
<div class="admon_content">
<p>The Java execution engine, the default execution engine since Logstash 7.0, is required
as Java plugins are not supported in the Ruby execution engine.</p>
</div>
</div>
<p>The expected Logstash output (excluding initialization) with the configuration above is:</p>
<div class="pre_wrapper lang-txt">
<pre class="programlisting prettyprint lang-txt">{
"@version" => "1",
"message" => "foo",
"@timestamp" => yyyy-MM-ddThh:mm:ss.SSSZ,
"host" => "<yourHostName>"
}
{
"@version" => "1",
"message" => "bar\n",
"@timestamp" => yyyy-MM-ddThh:mm:ss.SSSZ,
"host" => "<yourHostName>"
}</pre>
</div>
<h3><a id="_feedback_2"></a>Feedback<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/logstash/edit/7.11/docs/static/contributing-java-plugin.asciidoc">edit</a></h3>
<p>If you have any feedback on Java plugin support in Logstash, please comment on our
<a href="https://github.com/elastic/logstash/issues/9215" class="ulink" target="_top">main Github issue</a> or post in the
<a href="https://discuss.elastic.co/c/logstash" class="ulink" target="_top">Logstash forum</a>.</p>
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