How to enable automatic retries for Mongo Socket exception? - mongodb

Question

I'm running a spring boot gradle project. Spring boot version is 2.3.2.RELEASE, MongoDB version is 4.0.5.
Per below site, retryable writes are enabled by default from MongoDB 3.6+ https://docs.mongodb.com/manual/core/retryable-writes/
I saw the following exceptions in the project, MongoReadException and MongoWriteException while reading/saving to the mongo database. I would like to know if these exceptions are automatically retried starting Spring boot 2.3.2.RELEASE.
Below are the exceptions I wanted to retry,
Caused by: org.springframework.data.mongodb.UncategorizedMongoDbException: Exception sending message; nested exception is com.mongodb.MongoSocketWriteException: Exception sending message
Caused by: org.springframework.data.mongodb.UncategorizedMongoDbException: Prematurely reached end of stream; nested exception is com.mongodb.MongoSocketReadException: Prematurely reached end of stream
To try it out, I created a spring boot demo app in my local that tries to save a document to a database whose uri is provided with invalid value in the properties file. I get MongoTimeoutException on save document which is as expected. However, I don't see any retries on the save operation.
I also tried to add the property retryWrites=true to the connection uri, it didn't work
spring.data.mongodb.uri=mongodb://XXX:XXXX#invalid-server:5555/dummyDB?&retrywrites=true
Does anyone know how to enable the retries ? How do I test it locally ?
Please help. Thanks in advance.
Below is the exception stacktrace with MongoSocketOpenException. I would like to test if this exception is auto retried, however, it's not.
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}}]; 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}}]] with root cause
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}}]
at com.mongodb.internal.connection.BaseCluster.getDescription(BaseCluster.java:177) ~[mongodb-driver-core-4.0.5.jar:na]
at com.mongodb.internal.connection.SingleServerCluster.getDescription(SingleServerCluster.java:41) ~[mongodb-driver-core-4.0.5.jar:na]
at com.mongodb.client.internal.MongoClientDelegate.getConnectedClusterDescription(MongoClientDelegate.java:147) ~[mongodb-driver-sync-4.0.5.jar:na]
at com.mongodb.client.internal.MongoClientDelegate.createClientSession(MongoClientDelegate.java:98) ~[mongodb-driver-sync-4.0.5.jar:na]
at com.mongodb.client.internal.MongoClientDelegate$DelegateOperationExecutor.getClientSession(MongoClientDelegate.java:278) ~[mongodb-driver-sync-4.0.5.jar:na]
at com.mongodb.client.internal.MongoClientDelegate$DelegateOperationExecutor.execute(MongoClientDelegate.java:202) ~[mongodb-driver-sync-4.0.5.jar:na]
at com.mongodb.client.internal.MongoCollectionImpl.executeSingleWriteRequest(MongoCollectionImpl.java:1008) ~[mongodb-driver-sync-4.0.5.jar:na]
at com.mongodb.client.internal.MongoCollectionImpl.executeInsertOne(MongoCollectionImpl.java:469) ~[mongodb-driver-sync-4.0.5.jar:na]
at com.mongodb.client.internal.MongoCollectionImpl.insertOne(MongoCollectionImpl.java:452) ~[mongodb-driver-sync-4.0.5.jar:na]
at com.mongodb.client.internal.MongoCollectionImpl.insertOne(MongoCollectionImpl.java:446) ~[mongodb-driver-sync-4.0.5.jar:na]
at org.springframework.data.mongodb.core.MongoTemplate.lambda$insertDocument$15(MongoTemplate.java:1442) ~[spring-data-mongodb-3.0.2.RELEASE.jar:3.0.2.RELEASE]
at org.springframework.data.mongodb.core.MongoTemplate.execute(MongoTemplate.java:566) ~[spring-data-mongodb-3.0.2.RELEASE.jar:3.0.2.RELEASE]
at org.springframework.data.mongodb.core.MongoTemplate.insertDocument(MongoTemplate.java:1436) ~[spring-data-mongodb-3.0.2.RELEASE.jar:3.0.2.RELEASE]
at org.springframework.data.mongodb.core.MongoTemplate.doInsert(MongoTemplate.java:1236) ~[spring-data-mongodb-3.0.2.RELEASE.jar:3.0.2.RELEASE]
at org.springframework.data.mongodb.core.MongoTemplate.insert(MongoTemplate.java:1168) ~[spring-data-mongodb-3.0.2.RELEASE.jar:3.0.2.RELEASE]
at org.springframework.data.mongodb.repository.support.SimpleMongoRepository.save(SimpleMongoRepository.java:85) ~[spring-data-mongodb-3.0.2.RELEASE.jar:3.0.2.RELEASE]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_101]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_101]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_101]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_101]
at org.springframework.data.repository.core.support.ImplementationInvocationMetadata.invoke(ImplementationInvocationMetadata.java:72) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
at org.springframework.data.repository.core.support.RepositoryComposition$RepositoryFragments.invoke(RepositoryComposition.java:382) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
at org.springframework.data.repository.core.support.RepositoryComposition.invoke(RepositoryComposition.java:205) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$ImplementationMethodExecutionInterceptor.invoke(RepositoryFactorySupport.java:549) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.2.8.RELEASE.jar:5.2.8.RELEASE]
at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.doInvoke(QueryExecutorMethodInterceptor.java:155) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.invoke(QueryExecutorMethodInterceptor.java:130) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.2.8.RELEASE.jar:5.2.8.RELEASE]
at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:80) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.2.8.RELEASE.jar:5.2.8.RELEASE]
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:95) ~[spring-aop-5.2.8.RELEASE.jar:5.2.8.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.2.8.RELEASE.jar:5.2.8.RELEASE]
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212) ~[spring-aop-5.2.8.RELEASE.jar:5.2.8.RELEASE]
at com.sun.proxy.$Proxy52.save(Unknown Source) ~[na:na]

Answer 1

Retries apply to operations like reads and writes.
Operations are only sent once the driver successfully connects to the server(s) you indicate in connection string/client configuration.
Your server is not accessible by the client therefore that connection isn't working therefore no operations can be performed therefore the concept of operation retries doesn't apply.
The monitoring is retried automatically, once you fix the connectivity issue between the client and the server (or start the server) the client will recognize this automatically.