isopropylcyanide/dropwizard-jdbi-unitofwork

Provides Unit of Work Support for a JDBI based Dropwizard backend

Dropwizard Jdbi - Unit of Work Support

Provides a Unit of Work annotation for a Jdbi backed Dropwizard service for wrapping resource methods in a transaction context

• Dropwizard provides a very slick @UnitOfWork annotation that wraps a transaction context around resource methods annotated with this annotation. This is very useful for wrapping multiple calls in a single database transaction all of which will succeed or roll back atomically.

• However, this support is only available for Hibernate. For all the goodness Jdbi brings, we had to bring the transactionality on our own. This module provides support for JdbiUnitOfWork with a Jdbi backend

Maven Artifacts

This project is available on Maven Central. To add it to your project you can add the following dependency to your pom.xml:

<dependency>
    <groupId>com.github.isopropylcyanide</groupId>
    <artifactId>dropwizard-jdbi-unitofwork</artifactId>
    <version>1.2</version>
 </dependency>

Features

• transactionality across multiple datasources when called from a request thread
• transactionality across multiple datasources across multiple threads
• excluding selectively, certain set of URI's from transaction contexts, such as ELB, Health Checks etc
• Http GET methods are excluded from transaction by default.
• Http POST methods are wrapped around in a transaction only when annotated with @JdbiUnitOfWork

Usage

• Add the dependency to your pom.xml

• Construct a JdbiUnitOfWorkProvider from the DBI instance.

  JdbiUnitOfWorkProvider provider = JdbiUnitOfWorkProvider.withDefault(dbi); // most common
               or
  JdbiUnitOfWorkProvider provider = JdbiUnitOfWorkProvider.withLinked(dbi);

  If you are using Guice, you can bind the instance

  bind(JdbiUnitOfWorkProvider.class).toInstance(provider);
  

• Provide the list of package where the SQL Objects / DAO (to be attached) are located. Classes with Jdbi annotations @SqlQuery or @SqlUpdate or @SqlBatch or @SqlCall will be picked automatically.

  
  

  Use JdbiUnitOfWorkProvider to generate the proxies. You can also register the classes one by one.

  // class level
  SampleDao dao = (SampleDao) provider.getWrappedInstanceForDaoClass(SampleDao.class);
  // use the proxies and pass it as they were normal instances
  resource = new SampleResource(dao);
  
  // package level
  List<String> daoPackages = Lists.newArrayList("<fq-package-name>", "fq-package-name-2", ...);
  Map<? extends Class, Object> proxies = unitOfWorkProvider.getWrappedInstanceForDaoPackage(daoPackages);
  // use the proxies and pass it as they were normal instances
  resource = ...new SampleResource((SampleDao)proxies.get(SampleDao.class))

• Finally, we need to register the event listener with the Jersey Environment using the constructed provider

  environment.jersey().register(new JdbiUnitOfWorkApplicationEventListener(provider, new HashSet<>()));;
  

  In case you'd like to exclude certain URI paths from being monitored, you can pass them into exclude paths;

  Set<String> excludePaths = new HashSet<>();
  environment.jersey().register(new JdbiUnitOfWorkApplicationEventListener(handleManager, excludePaths));
  

• Start annotating resource methods with @JdbiUnitOfWork and you're good to go.

  @POST
  @Path("/")
  @JdbiUnitOfWork
  public RequestResponse createRequest() {
        ..do stateful work (across multiple Dao's)
        return response 
  }

Design

• This library relies on Jersey Monitoring Events to bind request lifecycle with a transaction aspect
• At the backend, all Jdbi objects such as Dao or SqlObjects are proxied behind a JdbiHandleManager
• JdbiHandleManager contract specifies the get and clear of the actual handles to the calling thread.

Support

Please file bug reports and feature requests in GitHub issues.

License

Copyright (c) 2020-2023 Aman Garg

This library is licensed under the Apache License, Version 2.0.

See http://www.apache.org/licenses/LICENSE-2.0.html or the LICENSE file in this repository for the full license text.

dropwizard-jdbi-unitofwork's Issues

JdbiUnitOfWork - 1.2 release is not found in maven

Hi @isopropylcyanide, thanks for this project. Are you continuing to maintain the project and do the new releases? The version is set to 1.2 in your examples, but the Maven public repositories don't have this version. Appreciate if there is any new release and if you can point me to it. Thank you

@JdbiUnitOfWork and @Transaction combinations?

Thanks for this great project! I have a question about combining @Transaction annotated methods in my DAO, and @JdbiUnitOfWork methods in resources (that use those methods).

Could this potentially mess up things (two different mechanisms to achieve the same thing)? Or can I keep both?