Add annotation to easily export prometheus metrics through the prometheus endpoint (#152)

Author: fiunchinho

simpleclient_spring_boot/src/main/java/io/prometheus/client/spring/boot/EnablePrometheusEndpoint.java

@@ -38,7 +38,7 @@
 @Target(ElementType.TYPE)
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
-@Import(PrometheusConfiguration.class)
+@Import(PrometheusEndpointConfiguration.class)
 public @interface EnablePrometheusEndpoint {
 
 }

simpleclient_spring_boot/src/main/java/io/prometheus/client/spring/boot/EnableSpringBootMetricsCollector.java

@@ -0,0 +1,17 @@
+package io.prometheus.client.spring.boot;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+import org.springframework.context.annotation.Import;
+
+
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+@Documented
+@Import(PrometheusMetricsConfiguration.class)
+public @interface EnableSpringBootMetricsCollector {
+
+}

simpleclient_spring_boot/src/main/java/io/prometheus/client/spring/boot/PrometheusConfiguration.java renamed to simpleclient_spring_boot/src/main/java/io/prometheus/client/spring/boot/PrometheusEndpointConfiguration.java

@@ -5,7 +5,7 @@
 import org.springframework.context.annotation.Configuration;
 
 @Configuration
-class PrometheusConfiguration {
+class PrometheusEndpointConfiguration {
 
   @Bean
   public PrometheusEndpoint prometheusEndpoint() {

simpleclient_spring_boot/src/main/java/io/prometheus/client/spring/boot/PrometheusMetricsConfiguration.java

@@ -0,0 +1,17 @@
+package io.prometheus.client.spring.boot;
+
+import java.util.Collection;
+import org.springframework.boot.actuate.endpoint.PublicMetrics;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+class PrometheusMetricsConfiguration {
+
+  @Bean
+  public SpringBootMetricsCollector springBootMetricsCollector(Collection<PublicMetrics> publicMetrics) {
+    SpringBootMetricsCollector springBootMetricsCollector = new SpringBootMetricsCollector(publicMetrics);
+    springBootMetricsCollector.register();
+    return springBootMetricsCollector;
+  }
+}