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@@ -19,7 +19,7 @@
consul:
host: localhost
port: 8500</pre><p>
</p><div class="caution" style="margin-left: 0.5in; margin-right: 0.5in;"><table border="0" summary="Caution"><tr><td rowspan="2" align="center" valign="top" width="25"><img alt="[Caution]" src="images/caution.png"></td><th align="left">Caution</th></tr><tr><td align="left" valign="top"><p>If you use <a class="link" href="multi_spring-cloud-consul-config.html" title="4.&nbsp;Distributed Configuration with Consul">Spring Cloud Consul Config</a>, the above values will need to be placed in <code class="literal">bootstrap.yml</code> instead of <code class="literal">application.yml</code>.</p></td></tr></table></div><p>The default service name, instance id and port, taken from the <code class="literal">Environment</code>, are <code class="literal">${spring.application.name}</code>, the Spring Context ID and <code class="literal">${server.port}</code> respectively.</p><p>To disable the Consul Discovery Client you can set <code class="literal">spring.cloud.consul.discovery.enabled</code> to <code class="literal">false</code>.</p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="_http_health_check" href="#_http_health_check"></a>3.3&nbsp;HTTP Health Check</h2></div></div></div><p>The health check for a Consul instance defaults to "/health", which is the default locations of a useful endpoint in a Spring Boot Actuator application. You need to change these, even for an Actuator application if you use a non-default context path or servlet path (e.g. <code class="literal">server.servletPath=/foo</code>) or management endpoint path (e.g. <code class="literal">management.context-path=/admin</code>). The interval that Consul uses to check the health endpoint may also be configured. "10s" and "1m" represent 10 seconds and 1 minute respectively. Example:</p><p><b>application.yml.&nbsp;</b>
</p><div class="caution" style="margin-left: 0.5in; margin-right: 0.5in;"><table border="0" summary="Caution"><tr><td rowspan="2" align="center" valign="top" width="25"><img alt="[Caution]" src="images/caution.png"></td><th align="left">Caution</th></tr><tr><td align="left" valign="top"><p>If you use <a class="link" href="multi_spring-cloud-consul-config.html" title="4.&nbsp;Distributed Configuration with Consul">Spring Cloud Consul Config</a>, the above values will need to be placed in <code class="literal">bootstrap.yml</code> instead of <code class="literal">application.yml</code>.</p></td></tr></table></div><p>The default service name, instance id and port, taken from the <code class="literal">Environment</code>, are <code class="literal">${spring.application.name}</code>, the Spring Context ID and <code class="literal">${server.port}</code> respectively.</p><p>To disable the Consul Discovery Client you can set <code class="literal">spring.cloud.consul.discovery.enabled</code> to <code class="literal">false</code>.</p><p>To disable the service registration you can set <code class="literal">spring.cloud.consul.discovery.register</code> to <code class="literal">false</code>.</p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="_http_health_check" href="#_http_health_check"></a>3.3&nbsp;HTTP Health Check</h2></div></div></div><p>The health check for a Consul instance defaults to "/health", which is the default locations of a useful endpoint in a Spring Boot Actuator application. You need to change these, even for an Actuator application if you use a non-default context path or servlet path (e.g. <code class="literal">server.servletPath=/foo</code>) or management endpoint path (e.g. <code class="literal">management.context-path=/admin</code>). The interval that Consul uses to check the health endpoint may also be configured. "10s" and "1m" represent 10 seconds and 1 minute respectively. Example:</p><p><b>application.yml.&nbsp;</b>
</p><pre class="screen">spring:
cloud:
consul:
@@ -38,7 +38,19 @@
consul:
discovery:
instanceId: ${spring.application.name}:${vcap.application.instance_id:${spring.application.instance_id:${random.value}}}</pre><p>
</p><p>With this metadata, and multiple service instances deployed on localhost, the random value will kick in there to make the instance unique. In Cloudfoundry the <code class="literal">vcap.application.instance_id</code> will be populated automatically in a Spring Boot application, so the random value will not be needed.</p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="_using_the_discoveryclient" href="#_using_the_discoveryclient"></a>3.4&nbsp;Using the DiscoveryClient</h2></div></div></div><p>Spring Cloud has support for <a class="link" href="https://github.com/spring-cloud/spring-cloud-netflix/blob/master/docs/src/main/asciidoc/spring-cloud-netflix.adoc#spring-cloud-feign" target="_top">Feign</a> (a REST client builder) and also <a class="link" href="https://github.com/spring-cloud/spring-cloud-netflix/blob/master/docs/src/main/asciidoc/spring-cloud-netflix.adoc#spring-cloud-ribbon" target="_top">Spring <code class="literal">RestTemplate</code></a> using the logical service names instead of physical URLs.</p><p>You can also use the <code class="literal">org.springframework.cloud.client.discovery.DiscoveryClient</code> which provides a simple API for discovery clients that is not specific to Netflix, e.g.</p><pre class="screen">@Autowired
</p><p>With this metadata, and multiple service instances deployed on localhost, the random value will kick in there to make the instance unique. In Cloudfoundry the <code class="literal">vcap.application.instance_id</code> will be populated automatically in a Spring Boot application, so the random value will not be needed.</p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="_looking_up_services" href="#_looking_up_services"></a>3.4&nbsp;Looking up services</h2></div></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="_using_ribbon" href="#_using_ribbon"></a>3.4.1&nbsp;Using Ribbon</h3></div></div></div><p>Spring Cloud has support for <a class="link" href="https://github.com/spring-cloud/spring-cloud-netflix/blob/master/docs/src/main/asciidoc/spring-cloud-netflix.adoc#spring-cloud-feign" target="_top">Feign</a> (a REST client builder) and also <a class="link" href="https://github.com/spring-cloud/spring-cloud-netflix/blob/master/docs/src/main/asciidoc/spring-cloud-netflix.adoc#spring-cloud-ribbon" target="_top">Spring <code class="literal">RestTemplate</code></a>
for looking up services using the logical service names/ids instead of physical URLs. Both Feign and the discovery-aware RestTemplate utilize <a class="link" href="http://cloud.spring.io/spring-cloud-netflix/single/spring-cloud-netflix.html#spring-cloud-ribbon" target="_top">Ribbon</a> for client-side load balancing.</p><p>If you want to access service STORES using the RestTemplate simply declare:</p><pre class="screen">@LoadBalanced
@Bean
public RestTemplate loadbalancedRestTemplate() {
new RestTemplate();
}</pre><p>and use it like this (notice how we use the STORES service name/id from Consul instead of a fully qualified domainname):</p><pre class="screen">@Autowired
RestTemplate restTemplate;
public String getFirstProduct() {
return this.restTemplate.getForObject("https://STORES/products/1", String.class);
}</pre><p>If you have Consul clusters in multiple datacenters and you want to access a service in another datacenter a service name/id alone is not enough. In that case
you use property <code class="literal">spring.cloud.consul.discovery.datacenters.STORES=dc-west</code> where <code class="literal">STORES</code> is the service name/id and <code class="literal">dc-west</code> is the datacenter
where the STORES service lives.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="_using_the_discoveryclient" href="#_using_the_discoveryclient"></a>3.4.2&nbsp;Using the DiscoveryClient</h3></div></div></div><p>You can also use the <code class="literal">org.springframework.cloud.client.discovery.DiscoveryClient</code> which provides a simple API for discovery clients that is not specific to Netflix, e.g.</p><pre class="screen">@Autowired
private DiscoveryClient discoveryClient;
public String serviceUrl() {
@@ -47,4 +59,4 @@ public String serviceUrl() {
return list.get(0).getUri();
}
return null;
}</pre></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="multi_spring-cloud-consul-agent.html">Prev</a>&nbsp;</td><td width="20%" align="center">&nbsp;</td><td width="40%" align="right">&nbsp;<a accesskey="n" href="multi_spring-cloud-consul-config.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">2.&nbsp;Consul Agent&nbsp;</td><td width="20%" align="center"><a accesskey="h" href="multi_spring-cloud-consul.html">Home</a></td><td width="40%" align="right" valign="top">&nbsp;4.&nbsp;Distributed Configuration with Consul</td></tr></table></div></body></html>
}</pre></div></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="multi_spring-cloud-consul-agent.html">Prev</a>&nbsp;</td><td width="20%" align="center">&nbsp;</td><td width="40%" align="right">&nbsp;<a accesskey="n" href="multi_spring-cloud-consul-config.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">2.&nbsp;Consul Agent&nbsp;</td><td width="20%" align="center"><a accesskey="h" href="multi_spring-cloud-consul.html">Home</a></td><td width="40%" align="right" valign="top">&nbsp;4.&nbsp;Distributed Configuration with Consul</td></tr></table></div></body></html>