Hi,
I faced a HikariCP leak that I thought was caused by my code but it appears that the use of StreamingResponseBody causes it by itself.
After removing all unneeded code, I come to a pretty straight forward reproduction case.
With StreamingResponseBody, one connection stays active forever in the CP. This connection is opened in one of my filter OncePerRequestFilter to fill a request-scoped component.
[UPDATE] see the next comment for a reproduction scenario (project zip included).
In a controller I directly call this service function:
@Override
@Transactional
public ResponseEntity<StreamingResponseBody> download() {
StreamingResponseBody stream = (o) -> {}
HttpHeaders headers = new HttpHeaders();
return new ResponseEntity(stream, headers, HttpStatus.OK);
}
com.zaxxer.hikari.pool.HikariPool : HikariPool-1 - After adding stats (total=6, active=1, idle=5, waiting=0)
When I just replace the type of response body to String, everything is ok:
@Override
@Transactional
public ResponseEntity download() {
HttpHeaders headers = new HttpHeaders();
return new ResponseEntity("", headers, HttpStatus.OK);
}
com.zaxxer.hikari.pool.HikariPool : HikariPool-1 - After cleanup stats (total=5, active=0, idle=5, waiting=0)
Here is my pom:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.someproject</groupId>
<artifactId>central</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>central</name>
<description>Central service for someproject Project</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.3.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<spring-cloud.version>Finchley.RELEASE</spring-cloud.version>
</properties>
<repositories>
<repository>
<id>repo.com.someproject.common-lib.releases</id>
<name>AWS Release Repository</name>
<url>s3://repo.com.someproject.common-lib/releases</url>
</repository>
<repository>
<id>repo.com.someproject.common-lib.snapshots</id>
<name>AWS Snapshot Repository</name>
<url>s3://repo.com.someproject.common-lib/snapshots</url>
</repository>
</repositories>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>com.amazonaws</groupId>
<artifactId>aws-java-sdk-bom</artifactId>
<version>1.11.297</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<!-- For HTTP Endpoints -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-aop</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
<!-- For Model -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.security</groupId>
<artifactId>spring-security-test</artifactId>
<version>5.1.2.RELEASE</version>
<scope>test</scope>
</dependency>
<!--For Mail -->
<dependency>
<groupId>javax.mail</groupId>
<artifactId>mail</artifactId>
<version>1.4.7</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.40</version>
</dependency>
<!-- For database migration -->
<dependency>
<groupId>org.flywaydb</groupId>
<artifactId>flyway-core</artifactId>
</dependency>
<dependency>
<groupId>com.amazonaws</groupId>
<artifactId>aws-java-sdk-s3</artifactId>
</dependency>
<dependency>
<groupId>com.amazonaws</groupId>
<artifactId>aws-java-sdk-sns</artifactId>
</dependency>
<dependency>
<groupId>commons-codec</groupId>
<artifactId>commons-codec</artifactId>
<version>1.11</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.auth0</groupId>
<artifactId>java-jwt</artifactId>
<version>3.3.0</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-config</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-oauth2</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-sleuth</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-zipkin</artifactId>
</dependency>
<dependency>
<groupId>org.modelmapper</groupId>
<artifactId>modelmapper</artifactId>
<version>2.3.1</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-hystrix</artifactId>
<version>1.1.5.RELEASE</version>
</dependency>
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger2</artifactId>
<version>2.9.2</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger-ui</artifactId>
<version>2.9.2</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>com.someproject</groupId>
<artifactId>common-lib</artifactId>
<version>0.0.6-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>org.flywaydb.flyway-test-extensions</groupId>
<artifactId>flyway-spring-test</artifactId>
<version>5.2.1</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
<finalName>legacy-service</finalName>
<extensions>
<extension>
<groupId>org.springframework.build</groupId>
<artifactId>aws-maven</artifactId>
<version>5.0.0.RELEASE</version>
</extension>
</extensions>
</build>
</project>
Some config:
@Configuration
@EnableTransactionManagement
public class AppConfig implements WebMvcConfigurer {
@Bean(name = "uploadTaskExecutor")
public TaskExecutor specificTaskExecutor() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(4);
executor.setMaxPoolSize(4);
executor.setThreadNamePrefix("Upload-");
executor.initialize();
return executor;
}
/**
* Fix: submitting a multipart request (multipart/form-data) using PUT.
* Normally, Spring just only support POST for submitting a multipart request.
*/
@Bean
public MultipartResolver multipartResolver() {
return new StandardServletMultipartResolver() {
@Override
public boolean isMultipart(HttpServletRequest request) {
String method = request.getMethod().toLowerCase();
//By default, only POST is allowed. Since this is an 'update' we should accept PUT.
if (!Arrays.asList("put", "post").contains(method)) {
return false;
}
String contentType = request.getContentType();
return (contentType != null &&contentType.toLowerCase().startsWith("multipart/"));
}
};
}
@Bean
JpaTransactionManager transactionManager(EntityManagerFactory entityManagerFactory) {
JpaTransactionManager transactionManager = new JpaTransactionManager();
transactionManager.setEntityManagerFactory(entityManagerFactory);
return transactionManager;
}
@Bean
public FilterRegistrationBean registerOpenSessionInViewFilterBean() {
FilterRegistrationBean registrationBean = new FilterRegistrationBean();
OpenEntityManagerInViewFilter filter = new OpenEntityManagerInViewFilter();
registrationBean.setFilter(filter);
registrationBean.setOrder(5);
return registrationBean;
}
@Bean
public FilterRegistrationBean requestContextFilterRegistration(){
FilterRegistrationBean filter = new FilterRegistrationBean();
filter.setFilter(requestContextFilter());
filter.setOrder(0);
return filter;
}
@Bean
public RequestContextFilter requestContextFilter(){
return new RequestContextFilter();
}
@Bean
public MessageSource messageSource() {
ResourceBundleMessageSource messageSource = new ResourceBundleMessageSource();
messageSource.setBasename("message/error_messages");
messageSource.setDefaultEncoding("UTF-8");
return messageSource;
}
@Override
public void configureContentNegotiation(ContentNegotiationConfigurer configurer) {
configurer.defaultContentType(MediaType.APPLICATION_XML);
}
@Override
public void addCorsMappings(CorsRegistry registry) {
//TODO: to modify after other dev
registry.addMapping("/**").allowedOrigins("*").allowedMethods("PUT", "DELETE","PATCH","GET","POST");
}
}
@Configuration
@EnableResourceServer
@EnableGlobalMethodSecurity(prePostEnabled = true)
@Profile("!test")
public class ResourceServerConfiguration extends BaseResourceServerConfiguration {
@Value("${auth-server.url}")
private String authEndpoint;
@Value("${security.oauth2.client.client-id}")
private String clientId;
@Value("${security.oauth2.client.client-secret}")
private String clientSecret;
@Override
public void configure(ResourceServerSecurityConfigurer resources) throws Exception {
resources.resourceId("ms/legacy");
}
@Bean
public ResourceServerTokenServices tokenService() {
RemoteTokenServices tokenServices = new RemoteTokenServices();
tokenServices.setClientId(clientId);
tokenServices.setClientSecret(clientSecret);
tokenServices.setCheckTokenEndpointUrl(authEndpoint + "/uaa/oauth/check_token");
return tokenServices;
}
}
My yml props:
server:
port: 8086
servlet:
context-path: /
spring:
profiles: local
application:
name: legacy-central-service
cloud:
config:
allow-override: true
override-none: true
zipkin:
enabled: true
base-url: http://localhost:8087/
sleuth:
sampler:
probability: 1.0
feign:
enabled: true
# JPA Configuration
jpa:
hibernate:
ddl-auto: validate
properties:
hibernate:
dialect: org.hibernate.dialect.MySQL5InnoDBDialect
datasource:
url: jdbc:mysql://localhost:3306/legacy_service?autoReconnect=true&useSSL=false
username: username
password: password
hikari:
maximum-pool-size: 20
minimum-idle: 5
idle-timeout: 600000
max-lifetime: 1800000
leak-detection-threshold: 60000
thymeleaf:
cache: false
mode: HTML
encoding: UTF-8
flyway:
baseline-on-migrate: true
# For Upload File - the max support file size is 500MB
servlet:
multipart:
enabled: true
max-file-size: 500MB
max-request-size: 500MB
location: /tmp
http:
multipart:
enabled: false
proj:
central:
mail:
from: contact@proj.com
host: localhost
port: 25
username:
password:
debug: false
video:
renderscore_tool_location: /tmp
eureka:
instance:
hostname: localhost
port: 8081
client:
registerWithEureka: true
fetchRegistry: true
serviceUrl:
defaultZone: http://${eureka.instance.hostname}:${eureka.instance.port}/eureka/
server:
wait-time-in-ms-when-sync-empty: 3000
auth-server:
url: http://localhost:8083
security:
oauth2:
client:
client-id: proj
client-secret: proj
resource:
user-info-uri: http://localhost:8082/uaa
jackson:
property-naming-strategy: SNAKE_CASE
serialization:
indent-output: true
authorization-service:
ribbon:
listOfServers: http://localhost:8083
legacy-central-service:
ribbon:
listOfServers: http://localhost:8086
static-data-service:
ribbon:
listOfServers: http://localhost:7071
**Comment From: PierreMardon**
I removed most of the classes of my project so that you can easily reproduce and inspect the relevant code only.
[sample-bug.zip](https://github.com/spring-projects/spring-boot/files/2800328/sample-bug.zip)
**EDIT**: the leak is caused by the use of `OpenEntityManagerInViewFilter` that fails to release the connection when `StreamingResponseBody` is used. Commenting it in `AppConfig.java` solves the leak. Still, I need this filter :P
To be able to start the app, you have to create an empty schema `test_schema` in a local MySQL database (configure your connection in `application.yml`).
- issue a GET request to `http://localhost:8086/ws3/file/data/?file=ANY_STRING`.
- the `GeneralFilter` class is the only one using JPA and calling the `MyUserRepository`, it's the only place where HikaryCP is asked for a connection.
- you'll see the hikary logs:
2019-01-27 18:54:01.350 DEBUG 18739 --- [l-1 housekeeper] com.zaxxer.hikari.pool.HikariPool : HikariPool-1 - Before cleanup stats (total=6, active=1, idle=5, waiting=0) 2019-01-27 18:54:01.351 DEBUG 18739 --- [l-1 housekeeper] com.zaxxer.hikari.pool.HikariPool : HikariPool-1 - After cleanup stats (total=6, active=1, idle=5, waiting=0)
And later the leak detection:
java.lang.Exception: Apparent connection leak detected at com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:128) ~[HikariCP-2.7.9.jar:na] at org.hibernate.engine.jdbc.connections.internal.DatasourceConnectionProviderImpl.getConnection(DatasourceConnectionProviderImpl.java:122) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.internal.NonContextualJdbcConnectionAccess.obtainConnection(NonContextualJdbcConnectionAccess.java:35) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.acquireConnectionIfNeeded(LogicalConnectionManagedImpl.java:106) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.getPhysicalConnection(LogicalConnectionManagedImpl.java:136) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.engine.jdbc.internal.StatementPreparerImpl.connection(StatementPreparerImpl.java:47) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.engine.jdbc.internal.StatementPreparerImpl$5.doPrepare(StatementPreparerImpl.java:145) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.engine.jdbc.internal.StatementPreparerImpl$StatementPreparationTemplate.prepareStatement(StatementPreparerImpl.java:171) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.engine.jdbc.internal.StatementPreparerImpl.prepareQueryStatement(StatementPreparerImpl.java:147) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1985) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1915) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1893) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.loader.Loader.doQuery(Loader.java:938) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:341) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.loader.Loader.doList(Loader.java:2692) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.loader.Loader.doList(Loader.java:2675) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2507) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.loader.Loader.list(Loader.java:2502) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:502) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:392) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:216) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1490) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.query.internal.AbstractProducedQuery.doList(AbstractProducedQuery.java:1445) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.query.internal.AbstractProducedQuery.list(AbstractProducedQuery.java:1414) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.query.internal.AbstractProducedQuery.getSingleResult(AbstractProducedQuery.java:1463) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.query.criteria.internal.compile.CriteriaQueryTypeQueryAdapter.getSingleResult(CriteriaQueryTypeQueryAdapter.java:107) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.springframework.data.jpa.repository.query.JpaQueryExecution$SingleEntityExecution.doExecute(JpaQueryExecution.java:214) ~[spring-data-jpa-2.0.8.RELEASE.jar:2.0.8.RELEASE] at org.springframework.data.jpa.repository.query.JpaQueryExecution.execute(JpaQueryExecution.java:91) ~[spring-data-jpa-2.0.8.RELEASE.jar:2.0.8.RELEASE] at org.springframework.data.jpa.repository.query.AbstractJpaQuery.doExecute(AbstractJpaQuery.java:136) ~[spring-data-jpa-2.0.8.RELEASE.jar:2.0.8.RELEASE] at org.springframework.data.jpa.repository.query.AbstractJpaQuery.execute(AbstractJpaQuery.java:125) ~[spring-data-jpa-2.0.8.RELEASE.jar:2.0.8.RELEASE] at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:590) ~[spring-data-commons-2.0.8.RELEASE.jar:2.0.8.RELEASE] at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:578) ~[spring-data-commons-2.0.8.RELEASE.jar:2.0.8.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE] at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:59) ~[spring-data-commons-2.0.8.RELEASE.jar:2.0.8.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE] at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:294) ~[spring-tx-5.0.7.RELEASE.jar:5.0.7.RELEASE] at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98) ~[spring-tx-5.0.7.RELEASE.jar:5.0.7.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE] at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:139) ~[spring-tx-5.0.7.RELEASE.jar:5.0.7.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE] at org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:135) ~[spring-data-jpa-2.0.8.RELEASE.jar:2.0.8.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE] at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE] at org.springframework.data.repository.core.support.SurroundingTransactionDetectorMethodInterceptor.invoke(SurroundingTransactionDetectorMethodInterceptor.java:61) ~[spring-data-commons-2.0.8.RELEASE.jar:2.0.8.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE] at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE] at com.sun.proxy.$Proxy96.findFirstByUuid(Unknown Source) ~[na:na] at com.myproject.filter.GeneralFilter.addRequestInfo(GeneralFilter.java:39) ~[classes/:na] ...
You can experiment that changing the `ResponseEntity` body type to `String` and returning an empty string fixes the leak.
**Comment From: PierreMardon**
I'm sorry for this bug report, in fact adding `@Async` annotation on my service function solves the issue, so it's not a bug, my bad !
**Comment From: PierreMardon**
Ok so indeed it would solve the leak but also any real IO transfert would fail (try to stream any resource in the body to see it).
So bad solution, still a bug, sorry for the premature closure!
**Comment From: wilkinsona**
Thanks for the sample but there's still quite a lot to it. If you have time to strip it down further, including replacing the need for MySQL with an in-memory database (H2 or HSQLDB), it will increase the changes of someone having the time to investigate.
**Comment From: PierreMardon**
I'm sorry to be that guy, but I prefer to tell you directly that I won't be able to take time to enhance the sample.
**Comment From: wilkinsona**
The problem is caused by a mis-configuration of the `OpenEntityManagerInViewFilter`. Its dispatcher types have not been customised so it is only called on request dispatch and is not called on async dispatch. As a result, the session that it opens is never closed which causes the database connection to leak.
**Comment From: alexpartsch**
So was this fixed? Still running in CP leakage when using `StreamingRequestBody` with JPA. Not sure, since the status `invalid` was applied on this issue.
**Comment From: wilkinsona**
@alexpartsch As far as we could determine, there was nothing to fix in Spring Boot as the problem was caused by misconfiguration in the application. Please see [my comment immediately above yours](https://github.com/spring-projects/spring-boot/issues/15794#issuecomment-461885252) for details.
**Comment From: alexpartsch**
@wilkinsona I read your comment, but was under assumption that the part of Spring Boot handling the `StreamingRequestBody` threading has to "customise the dispatcher types" (due to my lack of understanding of `OpenEntityManagerInViewFilter` I'm not aware of what these dispatcher types are and where one can customise them, but trying to find out now.), but as I understand from your last comment, the framework user is probably in charge of that.
**Comment From: wilkinsona**
The dispatcher types are part of the servlet spec and they govern the types of dispatch for which a filter is invoked. When you're using a `StreamingResponseBody` an async dispatch is performed so you need to be sure that the filter's been registered for async dispatches otherwise it won't get a chance to clean up properly once the response has been sent. You can configure the dispatcher types using a `FilterRegistrationBean`. Note that if you are using Spring Boot 2.3, the `OpenEntityManagerInViewFilter`, which is a `OncePerRequestFilter`, will be registered for async dispatches by default due to the changes made in https://github.com/spring-projects/spring-boot/issues/18953.
**Comment From: alexpartsch**
Thanks for the infos! I understand more know.
I'm running Spring Boot 2.3.3, but it seems no `OpenEntityManagerInViewFilter` is registered or at least executed on any request. I tried to define it myself but fail with a `LazyInitialisationException` due to no session being open in the async requests. Here is my filter bean definition:
@Bean
@Primary
public FilterRegistrationBean<OpenEntityManagerInViewFilter> openEntityManagerInViewFilterFilterRegistrationBean() {
var filter = new OpenEntityManagerInViewFilter();
var registrationBean = new FilterRegistrationBean<>(filter);
registrationBean.setAsyncSupported(true);
registrationBean.addUrlPatterns("/*");
registrationBean.setDispatcherTypes(DispatcherType.REQUEST, DispatcherType.ASYNC);
return registrationBean;
}
```
I use the default EntityManagerFactory configuration with hibernate so I don't think I need to configure more π€ ... but it still seems to not be executed. Since you say 2.3 already defines it as ASNY my leak can be caused by something else then π
Comment From: wilkinsona
my leak can be caused by something else then π
It certainly sounds like it. If you can provide us with a minimal sample project that reproduces the leak, please open a new issue and we can take a look.
Comment From: alexpartsch
Okay, so after defining my Bean as described above another error due to my transaction management was rissen. Fixing that, the new OpenEntityManagerInViewFilter seems to work fine now. Are you sure that DispatcherType.ASYNC is enabled by default in Spring Boot 2.3.3?
Comment From: wilkinsona
As sure as I can be. There's a test that verifies that's the case:
https://github.com/spring-projects/spring-boot/blob/602e62998eb2254517d695fa67246399ba40b8bf/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/FilterRegistrationBeanTests.java#L85-L92
Comment From: alexpartsch
Okay, found the issue, just for further reference: When testing with MockMvc and StreamingRequestBody one should use the asyncDispatch RequestBuilder for retrieving and properly handling the response (see here). I removed my OpenEntityManagerInViewFilter filter registration and it still worked πββοΈ
Thanks @wilkinsona for the help!