Add ConditionalOnGrpcServerEnabled flag

This adds a coarse-grained conditional guard that will disable the
server autoconfiguration if `spring.grpc.server.enabled` is set to
false or `BindableService` class is not available on the classpath.

Signed-off-by: Chris Bono <[email protected]>

spring-grpc-docs/src/main/antora/modules/ROOT/partials/_configprops.adoc

@@ -21,6 +21,7 @@
 |spring.grpc.client.enabled | `+++true+++` | Whether to enable client autoconfiguration.
 |spring.grpc.client.observations.enabled | `+++true+++` | Whether to enable Observations on the client.
 |spring.grpc.server.address |  | The address to bind to. could be a host:port combination or a pseudo URL like static://host:port. Can not be set if host or port are set independently.
+|spring.grpc.server.enabled | `+++true+++` | Whether to enable server autoconfiguration.
 |spring.grpc.server.exception-handling.enabled | `+++true+++` | Whether to enable user-defined global exception handling on the gRPC server.
 |spring.grpc.server.health.actuator.enabled | `+++true+++` | Whether to adapt Actuator health indicators into gRPC health checks.
 |spring.grpc.server.health.actuator.health-indicator-paths |  | List of Actuator health indicator paths to adapt into gRPC health checks.
@@ -49,4 +50,4 @@
 |spring.grpc.server.ssl.enabled |  | Whether to enable SSL support. Enabled automatically if "bundle" is provided unless specified otherwise.
 |spring.grpc.server.ssl.secure | `+++true+++` | Flag to indicate that client authentication is secure (i.e. certificates are checked). Do not set this to false in production.
 
-|===
+|===

spring-grpc-spring-boot-autoconfigure/src/main/java/org/springframework/grpc/autoconfigure/server/ConditionalOnGrpcServerEnabled.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2023-2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.grpc.autoconfigure.server;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.context.annotation.Conditional;
+
+import io.grpc.BindableService;
+
+/**
+ * {@link Conditional @Conditional} that only matches when the
+ * {@code io.grpc.BindableService} class is on the classpath and the
+ * {@code spring.grpc.server.enabled} property is not explicitly set to {@code false}.
+ *
+ * @author Freeman
+ * @author Chris Bono
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target({ ElementType.TYPE, ElementType.METHOD })
+@ConditionalOnClass(BindableService.class)
+@ConditionalOnProperty(prefix = "spring.grpc.server", name = "enabled", matchIfMissing = true)
+public @interface ConditionalOnGrpcServerEnabled {
+
+}

spring-grpc-spring-boot-autoconfigure/src/main/java/org/springframework/grpc/autoconfigure/server/GrpcServerAutoConfiguration.java

@@ -17,10 +17,8 @@
 
 import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.boot.autoconfigure.AutoConfiguration;
-import org.springframework.boot.autoconfigure.AutoConfigureAfter;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
-import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.context.ApplicationContext;
@@ -50,9 +48,8 @@
  * @author David Syer
  * @author Chris Bono
  */
-@AutoConfiguration
-@AutoConfigureAfter(GrpcServerFactoryAutoConfiguration.class)
-@ConditionalOnClass(BindableService.class)
+@AutoConfiguration(after = GrpcServerFactoryAutoConfiguration.class)
+@ConditionalOnGrpcServerEnabled
 @ConditionalOnBean(BindableService.class)
 @EnableConfigurationProperties(GrpcServerProperties.class)
 @Import({ GrpcCodecConfiguration.class })

spring-grpc-spring-boot-autoconfigure/src/main/java/org/springframework/grpc/autoconfigure/server/GrpcServerFactoryAutoConfiguration.java

@@ -54,7 +54,7 @@
  */
 @AutoConfiguration
 @AutoConfigureOrder(Ordered.HIGHEST_PRECEDENCE)
-@ConditionalOnClass(BindableService.class)
+@ConditionalOnGrpcServerEnabled
 @ConditionalOnBean(BindableService.class)
 public class GrpcServerFactoryAutoConfiguration {
 

spring-grpc-spring-boot-autoconfigure/src/main/java/org/springframework/grpc/autoconfigure/server/GrpcServerObservationAutoConfiguration.java

@@ -27,6 +27,7 @@
 
 @AutoConfiguration(
 		afterName = "org.springframework.boot.actuate.autoconfigure.observation.ObservationAutoConfiguration")
+@ConditionalOnGrpcServerEnabled
 @ConditionalOnClass({ ObservationRegistry.class, ObservationGrpcServerInterceptor.class })
 @ConditionalOnBean(ObservationRegistry.class)
 @ConditionalOnProperty(name = "spring.grpc.server.observation.enabled", havingValue = "true", matchIfMissing = true)

spring-grpc-spring-boot-autoconfigure/src/main/java/org/springframework/grpc/autoconfigure/server/GrpcServerReflectionAutoConfiguration.java

@@ -19,6 +19,7 @@
  * @author Haris Zujo
  */
 @AutoConfiguration(before = GrpcServerFactoryAutoConfiguration.class)
+@ConditionalOnGrpcServerEnabled
 @ConditionalOnClass(ProtoReflectionService.class)
 @ConditionalOnProperty(name = "spring.grpc.server.reflection.enabled", havingValue = "true", matchIfMissing = true)
 public class GrpcServerReflectionAutoConfiguration {

spring-grpc-spring-boot-autoconfigure/src/main/java/org/springframework/grpc/autoconfigure/server/exception/GrpcExceptionHandlerAutoConfiguration.java

@@ -15,15 +15,14 @@
  */
 package org.springframework.grpc.autoconfigure.server.exception;
 
-import java.util.stream.Collectors;
-
 import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.boot.autoconfigure.AutoConfiguration;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.context.annotation.Bean;
+import org.springframework.grpc.autoconfigure.server.ConditionalOnGrpcServerEnabled;
 import org.springframework.grpc.server.GlobalServerInterceptor;
 import org.springframework.grpc.server.exception.CompositeGrpcExceptionHandler;
 import org.springframework.grpc.server.exception.GrpcExceptionHandler;
@@ -32,6 +31,7 @@
 import io.grpc.Grpc;
 
 @AutoConfiguration
+@ConditionalOnGrpcServerEnabled
 @ConditionalOnClass(Grpc.class)
 @ConditionalOnBean(GrpcExceptionHandler.class)
 @ConditionalOnMissingBean(GrpcExceptionHandlerInterceptor.class)
@@ -44,7 +44,7 @@ public class GrpcExceptionHandlerAutoConfiguration {
 	public GrpcExceptionHandlerInterceptor globalExceptionHandlerInterceptor(
 			ObjectProvider<GrpcExceptionHandler> exceptionHandler) {
 		return new GrpcExceptionHandlerInterceptor(new CompositeGrpcExceptionHandler(
-				exceptionHandler.orderedStream().collect(Collectors.toList()).toArray(new GrpcExceptionHandler[0])));
+				exceptionHandler.orderedStream().toArray(GrpcExceptionHandler[]::new)));
 	}
 
 }

spring-grpc-spring-boot-autoconfigure/src/main/java/org/springframework/grpc/autoconfigure/server/health/GrpcServerHealthAutoConfiguration.java

@@ -43,6 +43,7 @@
 import org.springframework.context.annotation.Conditional;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.type.AnnotatedTypeMetadata;
+import org.springframework.grpc.autoconfigure.server.ConditionalOnGrpcServerEnabled;
 import org.springframework.grpc.autoconfigure.server.GrpcServerFactoryAutoConfiguration;
 import org.springframework.grpc.autoconfigure.server.GrpcServerProperties;
 import org.springframework.scheduling.annotation.EnableScheduling;
@@ -57,6 +58,7 @@
  * @author Chris Bono
  */
 @AutoConfiguration(before = GrpcServerFactoryAutoConfiguration.class)
+@ConditionalOnGrpcServerEnabled
 @ConditionalOnClass(HealthStatusManager.class)
 @ConditionalOnProperty(name = "spring.grpc.server.health.enabled", havingValue = "true", matchIfMissing = true)
 public class GrpcServerHealthAutoConfiguration {

spring-grpc-spring-boot-autoconfigure/src/main/java/org/springframework/grpc/autoconfigure/server/security/GrpcSecurityAutoConfiguration.java

@@ -23,6 +23,7 @@
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Conditional;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.grpc.autoconfigure.server.ConditionalOnGrpcServerEnabled;
 import org.springframework.grpc.autoconfigure.server.GrpcServerFactoryAutoConfiguration;
 import org.springframework.grpc.autoconfigure.server.exception.GrpcExceptionHandlerAutoConfiguration;
 import org.springframework.grpc.server.GlobalServerInterceptor;
@@ -40,6 +41,7 @@
 import io.grpc.internal.GrpcUtil;
 
 @ConditionalOnClass(ObjectPostProcessor.class)
+@ConditionalOnGrpcServerEnabled
 @AutoConfiguration(before = GrpcExceptionHandlerAutoConfiguration.class, after = SecurityAutoConfiguration.class)
 public class GrpcSecurityAutoConfiguration {
 
@@ -84,4 +86,4 @@ public <T extends ServerBuilder<T>> ServerBuilderCustomizer<T> securityContextEx
 
 	}
 
-}
+}

spring-grpc-spring-boot-autoconfigure/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -5,6 +5,12 @@
       "name": "spring.grpc.server.port",
       "defaultValue": "9090"
     },
+    {
+      "name": "spring.grpc.server.enabled",
+      "type": "java.lang.Boolean",
+      "description": "Whether to enable server autoconfiguration.",
+      "defaultValue": true
+    },
     {
       "name": "spring.grpc.server.reflection.enabled",
       "type": "java.lang.Boolean",

spring-grpc-spring-boot-autoconfigure/src/test/java/org/springframework/grpc/autoconfigure/server/GrpcServerAutoConfigurationTests.java

@@ -104,6 +104,25 @@ void whenNoBindableServicesRegisteredAutoConfigurationIsSkipped() {
 			.run((context) -> assertThat(context).doesNotHaveBean(GrpcServerAutoConfiguration.class));
 	}
 
+	@Test
+	void whenServerEnabledPropertySetFalseThenAutoConfigurationIsSkipped() {
+		this.contextRunner()
+			.withPropertyValues("spring.grpc.server.enabled=false")
+			.run((context) -> assertThat(context).doesNotHaveBean(GrpcServerAutoConfiguration.class));
+	}
+
+	@Test
+	void whenServerEnabledPropertyNotSetThenAutoConfigurationIsNotSkipped() {
+		this.contextRunner().run((context) -> assertThat(context).hasSingleBean(GrpcServerAutoConfiguration.class));
+	}
+
+	@Test
+	void whenServerEnabledPropertySetTrueThenAutoConfigurationIsNotSkipped() {
+		this.contextRunner()
+			.withPropertyValues("spring.grpc.server.enabled=true")
+			.run((context) -> assertThat(context).hasSingleBean(GrpcServerAutoConfiguration.class));
+	}
+
 	@Test
 	void whenHasUserDefinedServerLifecycleDoesNotAutoConfigureBean() {
 		GrpcServerLifecycle customServerLifecycle = mock(GrpcServerLifecycle.class);

spring-grpc-spring-boot-autoconfigure/src/test/java/org/springframework/grpc/autoconfigure/server/GrpcServerObservationAutoConfigurationTests.java

@@ -78,13 +78,32 @@ void whenObservationPropertyDisabledThenAutoConfigIsSkipped() {
 			.run(context -> assertThat(context).doesNotHaveBean(GrpcServerObservationAutoConfiguration.class));
 	}
 
+	@Test
+	void whenServerEnabledPropertySetFalseThenAutoConfigurationIsSkipped() {
+		this.validContextRunner()
+			.withPropertyValues("spring.grpc.server.enabled=false")
+			.run((context) -> assertThat(context).doesNotHaveBean(GrpcServerObservationAutoConfiguration.class));
+	}
+
+	@Test
+	void whenServerEnabledPropertyNotSetThenAutoConfigurationIsNotSkipped() {
+		this.validContextRunner()
+			.run((context) -> assertThat(context).hasSingleBean(GrpcServerObservationAutoConfiguration.class));
+	}
+
+	@Test
+	void whenServerEnabledPropertySetTrueThenAutoConfigurationIsNotSkipped() {
+		this.validContextRunner()
+			.withPropertyValues("spring.grpc.server.enabled=true")
+			.run((context) -> assertThat(context).hasSingleBean(GrpcServerObservationAutoConfiguration.class));
+	}
+
 	@Test
 	void whenAllConditionsAreMetThenInterceptorConfiguredAsExpected() {
-		this.validContextRunner().run((context) -> {
-			assertThat(context).hasSingleBean(ObservationGrpcServerInterceptor.class)
+		this.validContextRunner()
+			.run((context) -> assertThat(context).hasSingleBean(ObservationGrpcServerInterceptor.class)
 				.has(new Condition<>(beans -> beans.getBeansWithAnnotation(GlobalServerInterceptor.class).size() == 1,
-						"One global interceptor expected"));
-		});
+						"One global interceptor expected")));
 	}
 
 }

spring-grpc-spring-boot-autoconfigure/src/test/java/org/springframework/grpc/autoconfigure/server/GrpcServerReflectionAutoConfigurationTests.java

@@ -36,4 +36,23 @@ void whenReflectionDisabledThenSkipBeanCreation() {
 			.run((context) -> assertThat(context).doesNotHaveBean(BindableService.class));
 	}
 
+	@Test
+	void whenServerEnabledPropertySetFalseThenAutoConfigurationIsSkipped() {
+		this.contextRunner()
+			.withPropertyValues("spring.grpc.server.enabled=false")
+			.run((context) -> assertThat(context).doesNotHaveBean(BindableService.class));
+	}
+
+	@Test
+	void whenServerEnabledPropertyNotSetThenAutoConfigurationIsNotSkipped() {
+		this.contextRunner().run((context) -> assertThat(context).hasSingleBean(BindableService.class));
+	}
+
+	@Test
+	void whenServerEnabledPropertySetTrueThenAutoConfigurationIsNotSkipped() {
+		this.contextRunner()
+			.withPropertyValues("spring.grpc.server.enabled=true")
+			.run((context) -> assertThat(context).hasSingleBean(BindableService.class));
+	}
+
 }