Fix classNotFoundException when using old version of io.micrometer:micrometer-core

Author: echemezov

grpc-client-spring-boot-autoconfigure/src/main/java/net/devh/boot/grpc/client/autoconfigure/GrpcClientMetricAutoConfiguration.java

@@ -21,6 +21,7 @@
 import org.springframework.boot.autoconfigure.AutoConfigureAfter;
 import org.springframework.boot.autoconfigure.AutoConfigureBefore;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.annotation.Order;
@@ -40,6 +41,7 @@
 @AutoConfigureAfter(CompositeMeterRegistryAutoConfiguration.class)
 @AutoConfigureBefore(GrpcClientAutoConfiguration.class)
 @ConditionalOnBean(MeterRegistry.class)
+@ConditionalOnClass(MetricCollectingClientInterceptor.class)
 public class GrpcClientMetricAutoConfiguration {
 
     /**

grpc-server-spring-boot-autoconfigure/src/main/java/net/devh/boot/grpc/server/autoconfigure/GrpcServerMetricAutoConfiguration.java

@@ -32,6 +32,7 @@
 import org.springframework.boot.autoconfigure.AutoConfigureAfter;
 import org.springframework.boot.autoconfigure.AutoConfigureBefore;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -58,6 +59,7 @@
 @AutoConfigureAfter(CompositeMeterRegistryAutoConfiguration.class)
 @AutoConfigureBefore(GrpcServerAutoConfiguration.class)
 @ConditionalOnBean(MeterRegistry.class)
+@ConditionalOnClass(MetricCollectingServerInterceptor.class)
 public class GrpcServerMetricAutoConfiguration {
 
     @GrpcGlobalServerInterceptor