From 6464d6f1ec7dea817e72b2e9f415dcc93e76cd5a Mon Sep 17 00:00:00 2001
From: Michael Hoennig <michael.hoennig@hostsharing.net>
Date: Fri, 6 Dec 2024 10:08:26 +0100
Subject: [PATCH] linked metrics-endpoint (#132)
Co-authored-by: Michael Hoennig <michael@hoennig.de>
Reviewed-on: https://dev.hostsharing.net/hostsharing/hs.hsadmin.ng/pulls/132
Reviewed-by: Timotheus Pokorra <timotheus.pokorra@hostsharing.net>
---
.../config/CustomActuatorEndpoint.java | 44 +++++++++++++++++++
src/main/resources/application.yml | 3 +-
.../hsadminng/arch/ArchitectureTest.java | 2 +
.../CustomActuatorEndpointAcceptanceTest.java | 42 ++++++++++++++++++
src/test/resources/application.yml | 2 +-
5 files changed, 91 insertions(+), 2 deletions(-)
create mode 100644 src/main/java/net/hostsharing/hsadminng/config/CustomActuatorEndpoint.java
create mode 100644 src/test/java/net/hostsharing/hsadminng/config/CustomActuatorEndpointAcceptanceTest.java
diff --git a/src/main/java/net/hostsharing/hsadminng/config/CustomActuatorEndpoint.java b/src/main/java/net/hostsharing/hsadminng/config/CustomActuatorEndpoint.java
new file mode 100644
index 00000000..942ddbb9
--- /dev/null
+++ b/src/main/java/net/hostsharing/hsadminng/config/CustomActuatorEndpoint.java
@@ -0,0 +1,44 @@
+package net.hostsharing.hsadminng.config;
+
+import lombok.Getter;
+import org.springframework.boot.actuate.endpoint.annotation.Endpoint;
+import org.springframework.boot.actuate.endpoint.annotation.ReadOperation;
+import org.springframework.stereotype.Component;
+import org.springframework.web.client.RestTemplate;
+import org.springframework.web.servlet.support.ServletUriComponentsBuilder;
+
+import java.util.List;
+
+@Component
+@Endpoint(id="metric-links")
+// BLOG: implement a custom Spring Actuator endpoint to view _clickable_ Spring Actuator (Micrometer) Metrics endpoints
+// HOWTO: implement a custom Spring Actuator endpoint
+public class CustomActuatorEndpoint {
+
+ private final RestTemplate restTemplate = new RestTemplate();
+
+ @ReadOperation
+ public String getMetricsLinks() {
+ final String baseUrl = ServletUriComponentsBuilder.fromCurrentContextPath().build().toUriString();
+ final var metricsEndpoint = baseUrl + "/actuator/metrics";
+
+ final var response = restTemplate.getForObject(metricsEndpoint, ActuatorMetricsEndpointResource.class);
+
+ if (response == null || response.getNames() == null) {
+ throw new IllegalStateException("no metrics available");
+ }
+ return generateJsonLinksToMetricEndpoints(response, metricsEndpoint);
+ }
+
+ private static String generateJsonLinksToMetricEndpoints(final ActuatorMetricsEndpointResource response, final String metricsEndpoint) {
+ final var links = response.getNames().stream()
+ .map(name -> "\"" + name + "\": \"" + metricsEndpoint + "/" + name + "\"")
+ .toList();
+ return "{\n" + String.join(",\n", links) + "\n}";
+ }
+
+ @Getter
+ private static class ActuatorMetricsEndpointResource {
+ private List<String> names;
+ }
+}
diff --git a/src/main/resources/application.yml b/src/main/resources/application.yml
index 27020234..f75ae429 100644
--- a/src/main/resources/application.yml
+++ b/src/main/resources/application.yml
@@ -8,7 +8,8 @@ management:
endpoints:
web:
exposure:
- include: info, health, metrics
+ # HOWTO: view _clickable_ Spring Actuator (Micrometer) Metrics endpoints: http://localhost:8081/actuator/metric-links
+ include: info, health, metrics, metric-links
observations:
annotations:
enabled: true
diff --git a/src/test/java/net/hostsharing/hsadminng/arch/ArchitectureTest.java b/src/test/java/net/hostsharing/hsadminng/arch/ArchitectureTest.java
index 2628ad5d..2bf87f09 100644
--- a/src/test/java/net/hostsharing/hsadminng/arch/ArchitectureTest.java
+++ b/src/test/java/net/hostsharing/hsadminng/arch/ArchitectureTest.java
@@ -16,6 +16,7 @@ import net.hostsharing.hsadminng.hs.booking.item.HsBookingItem;
import net.hostsharing.hsadminng.hs.hosting.asset.HsHostingAssetRbacEntity;
import net.hostsharing.hsadminng.rbac.context.ContextBasedTest;
import net.hostsharing.hsadminng.rbac.grant.RbacGrantsDiagramService;
+import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.data.repository.Repository;
import org.springframework.web.bind.annotation.RestController;
@@ -120,6 +121,7 @@ public class ArchitectureTest {
@SuppressWarnings("unused")
public static final ArchRule configPackageRule = classes()
.that().resideInAPackage("..config..")
+ .and().areNotAnnotatedWith(SpringBootTest.class)
.should().onlyDependOnClassesThat()
.resideOutsideOfPackage(NET_HOSTSHARING_HSADMINNG);
diff --git a/src/test/java/net/hostsharing/hsadminng/config/CustomActuatorEndpointAcceptanceTest.java b/src/test/java/net/hostsharing/hsadminng/config/CustomActuatorEndpointAcceptanceTest.java
new file mode 100644
index 00000000..1509831e
--- /dev/null
+++ b/src/test/java/net/hostsharing/hsadminng/config/CustomActuatorEndpointAcceptanceTest.java
@@ -0,0 +1,42 @@
+package net.hostsharing.hsadminng.config;
+
+import io.restassured.RestAssured;
+import net.hostsharing.hsadminng.HsadminNgApplication;
+import net.hostsharing.hsadminng.test.DisableSecurityConfig;
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.web.server.LocalManagementPort;
+import org.springframework.test.context.ActiveProfiles;
+
+import static net.hostsharing.hsadminng.rbac.test.JsonMatcher.lenientlyEquals;
+
+@SpringBootTest(
+ webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT,
+ classes = { HsadminNgApplication.class, DisableSecurityConfig.class }
+)
+@ActiveProfiles("test")
+class CustomActuatorEndpointAcceptanceTest {
+
+ @LocalManagementPort
+ private Integer managementPort;
+
+ @Test
+ void shouldListMetricLinks() {
+ RestAssured // @formatter:off
+ .given()
+ .port(managementPort)
+ .when()
+ .get("http://localhost/actuator/metric-links")
+ .then().log().all().assertThat()
+ .statusCode(200)
+ .contentType("application/vnd.spring-boot.actuator.v3+json")
+ .body("", lenientlyEquals("""
+ {
+ "application.ready.time": "http://localhost:%{managementPort}/actuator/metrics/application.ready.time",
+ "application.started.time": "http://localhost:%{managementPort}/actuator/metrics/application.started.time"
+ }
+ """.replace("%{managementPort}", managementPort.toString())));
+ // @formatter:on
+ }
+
+}
diff --git a/src/test/resources/application.yml b/src/test/resources/application.yml
index a365daf3..f0df4e4b 100644
--- a/src/test/resources/application.yml
+++ b/src/test/resources/application.yml
@@ -6,7 +6,7 @@ management:
endpoints:
web:
exposure:
- include: info, health, metrics
+ include: info, health, metrics, metric-links
spring:
sql: