Add config property for http2 by default

samples/grpc-tomcat-secure/src/main/resources/application.properties

@@ -1,5 +1,4 @@
 spring.application.name=grpc-tomcat-secure
 server.port=9090
-server.http2.enabled=true
 spring.security.user.name=user
 spring.security.user.password=user

samples/grpc-tomcat/src/main/resources/application.properties

@@ -1,6 +1,5 @@
 spring.application.name=grpc-tomcat
 server.port=9090
-server.http2.enabled=true
 logging.pattern.level=%5p [${spring.application.name:},%X{traceId:-},%X{spanId:-}]
 logging.level.org.springframework.security=DEBUG
 management.endpoints.web.exposure.include=*

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

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2024-2024 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.util.Map;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.env.EnvironmentPostProcessor;
+import org.springframework.core.env.ConfigurableEnvironment;
+import org.springframework.core.env.MapPropertySource;
+import org.springframework.util.ClassUtils;
+
+public class ServletEnvironmentPostProcessor implements EnvironmentPostProcessor {
+
+	private static final boolean SERVLET_AVAILABLE = ClassUtils.isPresent("io.grpc.servlet.jakarta.GrpcServlet", null);
+
+	@Override
+	public void postProcessEnvironment(ConfigurableEnvironment environment, SpringApplication application) {
+		if (SERVLET_AVAILABLE) {
+			environment.getPropertySources()
+				.addFirst(new MapPropertySource("grpc-servlet", Map.of("server.http2.enabled", "true")));
+		}
+	}
+
+}

spring-grpc-spring-boot-autoconfigure/src/main/resources/META-INF/spring.factories

@@ -1,2 +1,5 @@
 org.springframework.security.config.annotation.web.configurers.AbstractHttpConfigurer=\
-org.springframework.grpc.autoconfigure.server.security.GrpcDisableCsrfHttpConfigurer
+org.springframework.grpc.autoconfigure.server.security.GrpcDisableCsrfHttpConfigurer
+
+org.springframework.boot.env.EnvironmentPostProcessor=\
+org.springframework.grpc.autoconfigure.server.ServletEnvironmentPostProcessor