SpringCloud/spring-cloud-commons
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Sync docs from master to gh-pages

Browse Source
This commit is contained in:
buildmaster
2019-08-27 18:57:47 +00:00
parent 840410254d
commit c1c388b251
3 changed files with 495 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

131
reference/html/spring-cloud-commons.html
View File

@@ -125,6 +125,18 @@ $(addBlockSwitches);
<li><a href="#_spring_cloud_compatibility_verification">Spring Cloud Compatibility Verification</a></li>
</ul>
</li>
<li><a href="#_spring_cloud_circuit_breaker">Spring Cloud Circuit Breaker</a></li>
<li><a href="#_introduction">Introduction</a>
<ul class="sectlevel2">
<li><a href="#_supported_implementations">Supported Implementations</a></li>
</ul>
</li>
<li><a href="#_core_concepts">Core Concepts</a>
<ul class="sectlevel2">
<li><a href="#_circuit_breakers_in_reactive_code">Circuit Breakers In Reactive Code</a></li>
</ul>
</li>
<li><a href="#_configuration">Configuration</a></li>
</ul>
</div>
</div>
@@ -1243,6 +1255,125 @@ of compatible Spring Boot versions.</p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_spring_cloud_circuit_breaker"><a class="link" href="#_spring_cloud_circuit_breaker">Spring Cloud Circuit Breaker</a></h2>
<div class="sectionbody">
</div>
</div>
<div class="sect1">
<h2 id="_introduction"><a class="link" href="#_introduction">Introduction</a></h2>
<div class="sectionbody">
<div class="paragraph">
<p>Spring Cloud Circuit breaker provides an abstraction across different circuit breaker implementations.
It provides a consistent API to use in your applications allowing you the developer to choose the circuit breaker implementation that best fits your needs for your app.</p>
</div>
<div class="sect2">
<h3 id="_supported_implementations"><a class="link" href="#_supported_implementations">Supported Implementations</a></h3>
<div class="ulist">
<ul>
<li>
<p><a href="https://github.com/Netflix/Hystrix">Netfix Hystrix</a></p>
</li>
<li>
<p><a href="https://github.com/resilience4j/resilience4j">Resilience4J</a></p>
</li>
<li>
<p><a href="https://github.com/alibaba/Sentinel">Sentinel</a></p>
</li>
<li>
<p><a href="https://github.com/spring-projects/spring-retry">Spring Retry</a></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_core_concepts"><a class="link" href="#_core_concepts">Core Concepts</a></h2>
<div class="sectionbody">
<div class="paragraph">
<p>To create a circuit breaker in your code you can use the <code>CircuitBreakerFactory</code> API. When you include a Spring Cloud Circuit Breaker starter on your classpath a bean implementing this API will automatically be created for you.
A very simple example of using this API is given below</p>
</div>
<div class="exampleblock">
<div class="content">
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-java hljs" data-lang="java">@Service
public static class DemoControllerService {
private RestTemplate rest;
private CircuitBreakerFactory cbFactory;
public DemoControllerService(RestTemplate rest, CircuitBreakerFactory cbFactory) {
this.rest = rest;
this.cbFactory = cbFactory;
}
public String slow() {
return cbFactory.create("slow").run(() -&gt; rest.getForObject("/slow", String.class), throwable -&gt; "fallback");
}
}</code></pre>
</div>
</div>
</div>
</div>
<div class="paragraph">
<p>The <code>CircuitBreakerFactory.create</code> API will create an instance of a class called <code>CircuitBreaker</code>.
The <code>run</code> method takes a <code>Supplier</code> and a <code>Function</code>.
The <code>Supplier</code> is the code that you are going to wrap in a circuit breaker.
The <code>Function</code> is the fallback that will be executed if the circuit breaker is tripped.
The function will be passed the <code>Throwable</code> that caused the fallback to be triggered.
You can optionally exclude the fallback if you do not want to provide one.</p>
</div>
<div class="sect2">
<h3 id="_circuit_breakers_in_reactive_code"><a class="link" href="#_circuit_breakers_in_reactive_code">Circuit Breakers In Reactive Code</a></h3>
<div class="paragraph">
<p>If Project Reactor is on the class path then you can also use <code>ReactiveCircuitBreakerFactory</code> for your reactive code.</p>
</div>
<div class="exampleblock">
<div class="content">
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-java hljs" data-lang="java">@Service
public static class DemoControllerService {
private ReactiveCircuitBreakerFactory cbFactory;
private WebClient webClient;
public DemoControllerService(WebClient webClient, ReactiveCircuitBreakerFactory cbFactory) {
this.webClient = webClient;
this.cbFactory = cbFactory;
}
public Mono&lt;String&gt; slow() {
return webClient.get().uri("/slow").retrieve().bodyToMono(String.class).transform(
it -&gt; cbFactory.create("slow").run(it, throwable -&gt; return Mono.just("fallback")));
}
}</code></pre>
</div>
</div>
</div>
</div>
<div class="paragraph">
<p>The <code>ReactiveCircuitBreakerFactory.create</code> API will create an instance of a class called <code>ReactiveCircuitBreaker</code>.
The <code>run</code> method takes with a <code>Mono</code> or <code>Flux</code> and wraps it in a circuit breaker.
You can optionally profile a fallback <code>Function</code> which will be called if the circuit breaker is tripped and will be passed the <code>Throwable</code>
that caused the failure.</p>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_configuration"><a class="link" href="#_configuration">Configuration</a></h2>
<div class="sectionbody">
<div class="paragraph">
<p>You can configure your circuit breakers using by creating beans of type <code>Customizer</code>.
The <code>Customizer</code> interface has a single method called <code>customize</code> that takes in the <code>Object</code> to customize.</p>
</div>
</div>
</div>
</div>
<script type="text/javascript" src="js/tocbot/tocbot.min.js"></script>
<script type="text/javascript" src="js/toc.js"></script>