fix: AutoConfigureAfter covers Spring Boot 3.5.x metrics package

gradle/libs.versions.toml

@@ -46,6 +46,7 @@ springJdbc = { module = "org.springframework:spring-jdbc", version.ref = "spring
 springBootAutoconfigure = { module = "org.springframework.boot:spring-boot-autoconfigure", version.ref = "springBoot" }
 springBootStarterValidation = { module = "org.springframework.boot:spring-boot-starter-validation", version.ref = "springBoot" }
 springBootTest = { module = "org.springframework.boot:spring-boot-test", version.ref = "springBoot" }
+springBootStarterActuator = { module = "org.springframework.boot:spring-boot-starter-actuator", version.ref = "springBoot" }
 assertjCore = { module = "org.assertj:assertj-core", version.ref = "assertj" }
 micrometerCore = { module = "io.micrometer:micrometer-core", version.ref = "micrometer" }
 micrometerTest = { module = "io.micrometer:micrometer-test", version.ref = "micrometer" }

okapi-spring-boot/build.gradle.kts

@@ -43,6 +43,8 @@ dependencies {
     testImplementation(libs.wiremock)
     testImplementation(project(":okapi-micrometer"))
     testImplementation(libs.micrometerCore)
+    // Brings in the metrics auto-config jar so @AutoConfigureAfter targets are resolvable in tests.
+    testImplementation(libs.springBootStarterActuator)
 }
 
 // CI version override: ./gradlew :okapi-spring-boot:test -PspringBootVersion=4.0.4 -PspringVersion=7.0.6

okapi-spring-boot/src/main/kotlin/com/softwaremill/okapi/springboot/OkapiMicrometerAutoConfiguration.kt

@@ -31,7 +31,12 @@ import java.time.Clock
  */
 @AutoConfiguration
 @AutoConfigureAfter(
-    name = ["org.springframework.boot.micrometer.metrics.autoconfigure.CompositeMeterRegistryAutoConfiguration"],
+    name = [
+        // Spring Boot 3.5.x
+        "org.springframework.boot.actuate.autoconfigure.metrics.CompositeMeterRegistryAutoConfiguration",
+        // Spring Boot 4.0.x
+        "org.springframework.boot.micrometer.metrics.autoconfigure.CompositeMeterRegistryAutoConfiguration",
+    ],
 )
 @ConditionalOnClass(name = ["io.micrometer.core.instrument.MeterRegistry"])
 @ConditionalOnBean(MeterRegistry::class)

okapi-spring-boot/src/test/kotlin/com/softwaremill/okapi/springboot/OutboxProcessorAutoConfigurationTest.kt

@@ -8,10 +8,13 @@ import com.softwaremill.okapi.core.OutboxStore
 import com.softwaremill.okapi.micrometer.MicrometerOutboxListener
 import com.softwaremill.okapi.micrometer.MicrometerOutboxMetrics
 import com.softwaremill.okapi.micrometer.OutboxMetricsRefresher
+import io.kotest.assertions.withClue
 import io.kotest.core.spec.style.FunSpec
+import io.kotest.matchers.collections.shouldNotBeEmpty
 import io.kotest.matchers.nulls.shouldNotBeNull
 import io.kotest.matchers.shouldBe
 import org.springframework.boot.autoconfigure.AutoConfigurations
+import org.springframework.boot.autoconfigure.AutoConfigureAfter
 import org.springframework.boot.test.context.runner.ApplicationContextRunner
 import org.springframework.jdbc.datasource.SimpleDriverDataSource
 import java.time.Duration.ofMillis
@@ -90,7 +93,7 @@ class OutboxProcessorAutoConfigurationTest : FunSpec({
         }
     }
 
-    test("listener, metrics and refresher are wired when MeterRegistry is present") {
+    test("listener, metrics and refresher are wired when a MeterRegistry bean is provided directly") {
         contextRunner
             .withBean(io.micrometer.core.instrument.MeterRegistry::class.java, {
                 io.micrometer.core.instrument.simple.SimpleMeterRegistry()
@@ -124,8 +127,87 @@ class OutboxProcessorAutoConfigurationTest : FunSpec({
                 props.refreshInterval shouldBe ofSeconds(15)
             }
     }
+
+    // Exercises real Spring Boot metrics auto-config ordering: MeterRegistry is created by SimpleMetricsExportAutoConfiguration
+    // (not pre-registered as a user bean), so @AutoConfigureAfter on OkapiMicrometerAutoConfiguration must actually resolve
+    // and order correctly for the listener to be wired.
+    test("listener is wired under real Spring Boot metrics auto-config ordering") {
+        // Each pair lists the same auto-config in 3.5.x (`actuate.autoconfigure.metrics`) and 4.0.x (`micrometer.metrics.autoconfigure`) layouts.
+        val metricsAutoConfig = resolveSpringBootClass(
+            "org.springframework.boot.actuate.autoconfigure.metrics.MetricsAutoConfiguration",
+            "org.springframework.boot.micrometer.metrics.autoconfigure.MetricsAutoConfiguration",
+        )
+        val compositeMeterRegistryAutoConfig = resolveSpringBootClass(
+            "org.springframework.boot.actuate.autoconfigure.metrics.CompositeMeterRegistryAutoConfiguration",
+            "org.springframework.boot.micrometer.metrics.autoconfigure.CompositeMeterRegistryAutoConfiguration",
+        )
+        val simpleMetricsExportAutoConfig = resolveSpringBootClass(
+            "org.springframework.boot.actuate.autoconfigure.metrics.export.simple.SimpleMetricsExportAutoConfiguration",
+            "org.springframework.boot.micrometer.metrics.autoconfigure.export.simple.SimpleMetricsExportAutoConfiguration",
+        )
+
+        ApplicationContextRunner()
+            .withConfiguration(
+                AutoConfigurations.of(
+                    OutboxAutoConfiguration::class.java,
+                    OkapiMicrometerAutoConfiguration::class.java,
+                    metricsAutoConfig,
+                    compositeMeterRegistryAutoConfig,
+                    simpleMetricsExportAutoConfig,
+                ),
+            )
+            .withBean(OutboxStore::class.java, { stubStore() })
+            .withBean(MessageDeliverer::class.java, { stubDeliverer() })
+            .withBean(DataSource::class.java, { SimpleDriverDataSource() })
+            .run { ctx ->
+                ctx.getBean(io.micrometer.core.instrument.MeterRegistry::class.java).shouldNotBeNull()
+                ctx.getBean(MicrometerOutboxListener::class.java).shouldNotBeNull()
+                ctx.getBean(MicrometerOutboxMetrics::class.java).shouldNotBeNull()
+                ctx.getBean(OutboxMetricsRefresher::class.java).shouldNotBeNull()
+            }
+    }
+
+    // @AutoConfigureAfter(name = ...) silently drops entries whose class is missing — if none resolve, the ordering hint is a no-op.
+    test("AutoConfigureAfter on OkapiMicrometerAutoConfiguration resolves on the runtime classpath") {
+        val annotation = OkapiMicrometerAutoConfiguration::class.java.getAnnotation(AutoConfigureAfter::class.java)
+        annotation.shouldNotBeNull()
+
+        val declaredNames = annotation.name.toList()
+        declaredNames.shouldNotBeEmpty()
+
+        val classLoader = OkapiMicrometerAutoConfiguration::class.java.classLoader
+        val resolvable = declaredNames.filter { name ->
+            try {
+                Class.forName(name, false, classLoader)
+                true
+            } catch (_: ClassNotFoundException) {
+                false
+            }
+        }
+
+        withClue(
+            "None of the @AutoConfigureAfter targets $declaredNames resolve on this Spring Boot runtime; " +
+                "the ordering hint is silently ignored and OkapiMicrometerAutoConfiguration may be evaluated " +
+                "before MeterRegistry is registered.",
+        ) {
+            resolvable.shouldNotBeEmpty()
+        }
+    }
 })
 
+// Loads a Spring Boot auto-config class by trying version-specific FQCNs in order.
+// Lets a single test exercise both the 3.5.x (`...actuate.autoconfigure.metrics...`) and 4.0.x (`...micrometer.metrics.autoconfigure...`) layouts.
+private fun resolveSpringBootClass(vararg candidateFqcns: String): Class<*> {
+    val classLoader = OkapiMicrometerAutoConfiguration::class.java.classLoader
+    return candidateFqcns.firstNotNullOfOrNull { fqcn ->
+        try {
+            Class.forName(fqcn, false, classLoader)
+        } catch (_: ClassNotFoundException) {
+            null
+        }
+    } ?: error("None of $candidateFqcns resolves on this Spring Boot runtime; check spring-boot-starter-actuator on the test classpath.")
+}
+
 private fun stubStore() = object : OutboxStore {
     override fun persist(entry: OutboxEntry) = entry
     override fun claimPending(limit: Int) = emptyList<OutboxEntry>()