Skip config server bootstrapper if not on classpath

spring-cloud-consul-discovery/src/main/java/org/springframework/cloud/consul/discovery/configclient/ConsulConfigServerBootstrapper.java

@@ -29,11 +29,15 @@ import org.springframework.cloud.consul.ConsulAutoConfiguration;
 import org.springframework.cloud.consul.ConsulProperties;
 import org.springframework.cloud.consul.discovery.ConsulDiscoveryClient;
 import org.springframework.cloud.consul.discovery.ConsulDiscoveryProperties;
+import org.springframework.util.ClassUtils;
 
 public class ConsulConfigServerBootstrapper implements Bootstrapper {
 
 	@Override
 	public void intitialize(BootstrapRegistry registry) {
+		if (!ClassUtils.isPresent("org.springframework.cloud.config.client.ConfigServerInstanceProvider", null)) {
+			return;
+		}
 		registry.registerIfAbsent(ConsulProperties.class, context -> {
 			Binder binder = context.get(Binder.class);
 			return binder.bind(ConsulProperties.PREFIX, ConsulProperties.class).orElseGet(ConsulProperties::new);

spring-cloud-consul-discovery/src/test/java/org/springframework/cloud/consul/discovery/configclient/ConsulConfigServerBootstrapperNoConfigClientTests.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2015-2020 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.cloud.consul.discovery.configclient;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.springframework.boot.SpringBootConfiguration;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.cloud.test.ClassPathExclusions;
+import org.springframework.cloud.test.ModifiedClassPathRunner;
+
+@RunWith(ModifiedClassPathRunner.class)
+@ClassPathExclusions({ "spring-cloud-config-client-*.jar", "spring-cloud-config-server-*.jar" })
+public class ConsulConfigServerBootstrapperNoConfigClientTests {
+
+	@Test
+	public void enabledAddsInstanceProviderFn() {
+		new SpringApplicationBuilder(TestConfig.class).properties("spring.cloud.config.discovery.enabled=true",
+				"spring.cloud.service-registry.auto-registration.enabled=false").run().close();
+	}
+
+	@SpringBootConfiguration
+	@EnableAutoConfiguration
+	static class TestConfig {
+
+	}
+
+}