今天使用使用Spring-Boot的时候，启动的时候报错了，主要信息：
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mongoTemplate' defined in class path resource [org/springframework/boot/autoconfigure/data/mongo/MongoDataAutoConfiguration.class]
详细报错信息如下：
2018-12-05 17:52:31.855 ERROR Application run failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mongoTemplate' defined in class path resource [org/springframework/boot/autoconfigure/data/mongo/MongoDataAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.data.mongodb.core.MongoTemplate]: Factory method 'mongoTemplate' threw exception; nested exception is org.springframework.dao.DataAccessResourceFailureException: Timed out after 30000 ms while waiting to connect. Client view of cluster state is {type=UNKNOWN, servers=[{address=localhost:27017, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketOpenException: Exception opening socket}, caused by {java.net.ConnectException: Connection refused: connect}}]; nested exception is com.mongodb.MongoTimeoutException: Timed out after 30000 ms while waiting to connect. Client view of cluster state is {type=UNKNOWN, servers=[{address=localhost:27017, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketOpenException: Exception opening socket}, caused by {java.net.ConnectException: Connection refused: connect}}]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:590) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1247) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1096) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:535) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:495) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:759) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:869) ~[spring-context-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) ~[spring-context-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) ~[spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:780) [spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:412) [spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:333) [spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1277) [spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1265) [spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at cn.xlink.YuanQiClient.main(YuanQiClient.java:16) [classes/:?]
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.data.mongodb.core.MongoTemplate]: Factory method 'mongoTemplate' threw exception; nested exception is org.springframework.dao.DataAccessResourceFailureException: Timed out after 30000 ms while waiting to connect. Client view of cluster state is {type=UNKNOWN, servers=[{address=localhost:27017, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketOpenException: Exception opening socket}, caused by {java.net.ConnectException: Connection refused: connect}}]; nested exception is com.mongodb.MongoTimeoutException: Timed out after 30000 ms while waiting to connect. Client view of cluster state is {type=UNKNOWN, servers=[{address=localhost:27017, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketOpenException: Exception opening socket}, caused by {java.net.ConnectException: Connection refused: connect}}]
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:582) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
... 18 more
Caused by: org.springframework.dao.DataAccessResourceFailureException: Timed out after 30000 ms while waiting to connect. Client view of cluster state is {type=UNKNOWN, servers=[{address=localhost:27017, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketOpenException: Exception opening socket}, caused by {java.net.ConnectException: Connection refused: connect}}]; nested exception is com.mongodb.MongoTimeoutException: Timed out after 30000 ms while waiting to connect. Client view of cluster state is {type=UNKNOWN, servers=[{address=localhost:27017, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketOpenException: Exception opening socket}, caused by {java.net.ConnectException: Connection refused: connect}}]
at org.springframework.data.mongodb.core.MongoExceptionTranslator.translateExceptionIfPossible(MongoExceptionTranslator.java:88) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.MongoTemplate.potentiallyConvertRuntimeException(MongoTemplate.java:2607) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.DefaultIndexOperations.execute(DefaultIndexOperations.java:194) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.DefaultIndexOperations.ensureIndex(DefaultIndexOperations.java:97) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.index.MongoPersistentEntityIndexCreator.createIndex(MongoPersistentEntityIndexCreator.java:145) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.index.MongoPersistentEntityIndexCreator.checkForAndCreateIndexes(MongoPersistentEntityIndexCreator.java:135) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.index.MongoPersistentEntityIndexCreator.checkForIndexes(MongoPersistentEntityIndexCreator.java:127) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.index.MongoPersistentEntityIndexCreator.<init>(MongoPersistentEntityIndexCreator.java:93) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.index.MongoPersistentEntityIndexCreator.<init>(MongoPersistentEntityIndexCreator.java:70) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.MongoTemplate.<init>(MongoTemplate.java:241) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration.mongoTemplate(MongoDataAutoConfiguration.java:99) ~[spring-boot-autoconfigure-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration$$EnhancerBySpringCGLIB$$6af1ca95.CGLIB$mongoTemplate$4(<generated>) ~[spring-boot-autoconfigure-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration$$EnhancerBySpringCGLIB$$6af1ca95$$FastClassBySpringCGLIB$$640cc4ce.invoke(<generated>) ~[spring-boot-autoconfigure-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228) ~[spring-core-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:365) ~[spring-context-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration$$EnhancerBySpringCGLIB$$6af1ca95.mongoTemplate(<generated>) ~[spring-boot-autoconfigure-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_144]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_144]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_144]
at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_144]
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:582) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
... 18 more
Caused by: com.mongodb.MongoTimeoutException: Timed out after 30000 ms while waiting to connect. Client view of cluster state is {type=UNKNOWN, servers=[{address=localhost:27017, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketOpenException: Exception opening socket}, caused by {java.net.ConnectException: Connection refused: connect}}]
at com.mongodb.connection.BaseCluster.getDescription(BaseCluster.java:167) ~[mongo-java-driver-3.6.4.jar:?]
at com.mongodb.Mongo.getConnectedClusterDescription(Mongo.java:885) ~[mongo-java-driver-3.6.4.jar:?]
at com.mongodb.Mongo.createClientSession(Mongo.java:877) ~[mongo-java-driver-3.6.4.jar:?]
at com.mongodb.Mongo$3.getClientSession(Mongo.java:866) ~[mongo-java-driver-3.6.4.jar:?]
at com.mongodb.Mongo$3.execute(Mongo.java:834) ~[mongo-java-driver-3.6.4.jar:?]
at com.mongodb.MongoCollectionImpl.executeCreateIndexes(MongoCollectionImpl.java:867) ~[mongo-java-driver-3.6.4.jar:?]
at com.mongodb.MongoCollectionImpl.createIndexes(MongoCollectionImpl.java:820) ~[mongo-java-driver-3.6.4.jar:?]
at com.mongodb.MongoCollectionImpl.createIndexes(MongoCollectionImpl.java:815) ~[mongo-java-driver-3.6.4.jar:?]
at com.mongodb.MongoCollectionImpl.createIndex(MongoCollectionImpl.java:800) ~[mongo-java-driver-3.6.4.jar:?]
at org.springframework.data.mongodb.core.DefaultIndexOperations.lambda$ensureIndex$0(DefaultIndexOperations.java:111) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.DefaultIndexOperations.execute(DefaultIndexOperations.java:192) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.DefaultIndexOperations.ensureIndex(DefaultIndexOperations.java:97) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.index.MongoPersistentEntityIndexCreator.createIndex(MongoPersistentEntityIndexCreator.java:145) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.index.MongoPersistentEntityIndexCreator.checkForAndCreateIndexes(MongoPersistentEntityIndexCreator.java:135) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.index.MongoPersistentEntityIndexCreator.checkForIndexes(MongoPersistentEntityIndexCreator.java:127) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.index.MongoPersistentEntityIndexCreator.<init>(MongoPersistentEntityIndexCreator.java:93) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.index.MongoPersistentEntityIndexCreator.<init>(MongoPersistentEntityIndexCreator.java:70) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.data.mongodb.core.MongoTemplate.<init>(MongoTemplate.java:241) ~[spring-data-mongodb-2.0.10.RELEASE.jar:2.0.10.RELEASE]
at org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration.mongoTemplate(MongoDataAutoConfiguration.java:99) ~[spring-boot-autoconfigure-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration$$EnhancerBySpringCGLIB$$6af1ca95.CGLIB$mongoTemplate$4(<generated>) ~[spring-boot-autoconfigure-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration$$EnhancerBySpringCGLIB$$6af1ca95$$FastClassBySpringCGLIB$$640cc4ce.invoke(<generated>) ~[spring-boot-autoconfigure-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228) ~[spring-core-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:365) ~[spring-context-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration$$EnhancerBySpringCGLIB$$6af1ca95.mongoTemplate(<generated>) ~[spring-boot-autoconfigure-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_144]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_144]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_144]
at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_144]
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:582) ~[spring-beans-5.0.9.RELEASE.jar:5.0.9.RELEASE]
... 18 more
百度了一下，没找到相似的问题，受这篇博客的影响：
https://www.cnblogs.com/TinyBobo/p/7850372.html
仔细检查了一下自己的pom文件以及自己项目发现了问题；具体分析如下：
1、首先说下我的项目结构是这样的，采用的是dubbo的分布式部署的项目方式。
2、client端根本没有mongo的配置依赖，怎么会报mongo的错误呢，百思不得其解。
3、后来发现了我依赖api，api中有mongo的配置
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-mongodb</artifactId>
</dependency>问题就出来了，我client端配置了这个，又是Spring-Boot的项目，他会注入去找实现方法，发现没有，就会报错了。
所以解决方法有两个，
1、把相关的mongo的依赖配置，转移到server端中。
2、把client的中无用的mongo依赖移除即可，如下:
<dependency>
<groupId>cn.XXX</groupId>
<artifactId>XXX-api</artifactId>
<exclusions>
<exclusion>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-mongodb</artifactId>
</exclusion>
</exclusions>
<version>1.0.0</version>
</dependency>大致就是这些，如果错漏欢迎指正。